PCF2129
Accurate RTC with integrated quartz crystal for industrial
applications
Rev. 7 — 19 December 2014
Product data sheet
1. General description
The PCF2129 is a CMOS1 Real Time Clock (RTC) and calendar with an integrated
Temperature Compensated Crystal (Xtal) Oscillator (TCXO) and a 32.768 kHz quartz
crystal optimized for very high accuracy and very low power consumption. The PCF2129
has a selectable I2C-bus or SPI-bus, a backup battery switch-over circuit, a
programmable watchdog function, a timestamp function, and many other features.
For a selection of NXP Real-Time Clocks, see Table 83 on page 75
2. Features and benefits
Operating temperature range from 40 C to +85 C
Temperature Compensated Crystal Oscillator (TCXO) with integrated capacitors
Typical accuracy:
PCF2129AT: 3 ppm from 15 C to +60 C
PCF2129T: 3 ppm from 30 C to +80 C
Integration of a 32.768 kHz quartz crystal and oscillator in the same package
Provides year, month, day, weekday, hours, minutes, seconds, and leap year
correction
Timestamp function
with interrupt capability
detection of two different events on one multilevel input pin (for example, for tamper
detection)
Two line bidirectional 400 kHz Fast-mode I2C-bus interface
3 line SPI-bus with separate data input and output (maximum speed 6.5 Mbit/s)
Battery backup input pin and switch-over circuitry
Battery backed output voltage
Battery low detection function
Power-On Reset Override (PORO)
Oscillator stop detection function
Interrupt output (open-drain)
Programmable 1 second or 1 minute interrupt
Programmable watchdog timer with interrupt
Programmable alarm function with interrupt capability
Programmable square output
1.
The definition of the abbreviations and acronyms used in this data sheet can be found in Section 20.
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
Clock operating voltage: 1.8 V to 4.2 V
Low supply current: typical 0.70 A at VDD = 3.3 V
3. Applications
Electronic metering for electricity, water, and gas
Precision timekeeping
Access to accurate time of the day
GPS equipment to reduce time to first fix
Applications that require an accurate process timing
Products with long automated unattended operation time
4. Ordering information
Table 1.
Ordering information
Type number
Package
Name
Description
Version
PCF2129AT
SO20
plastic small outline package; 20 leads; SOT163-1
body width 7.5 mm
PCF2129T
SO16
plastic small outline package; 16 leads; SOT162-1
body width 7.5 mm
4.1 Ordering options
Table 2.
Ordering options
Product type number
Orderable part number Sales item
(12NC)
Delivery form
IC
revision
PCF2129AT/2
PCF2129AT/2,518
935295732518
tape and reel, 13 inch, dry pack
2
PCF2129T/2
PCF2129T/2,518
935297464518
tape and reel, 13 inch, dry pack
2
5. Marking
Table 3.
PCF2129
Product data sheet
Marking codes
Product type number
Marking code
PCF2129AT/2
PCF2129AT
PCF2129T/2
PCF2129T
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
2 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
6. Block diagram
,17
7&;2
26&,
',9,'(5
$1'
7,0(5
N+]
26&2
&/.287
9''
9%$7
966
7(03
%$77(5<%$&.83
6:,7&+29(5
&,5&8,75<
+]
LQWHUQDORSHUDWLQJ
YROWDJH9RSHULQW
/2*,&
&21752/
%%6
26&,//$725
021,725
5(6(7
63,%86
,17(5)$&(
$''5(66
5(*,67(5
6'$&(
6'2
6',
6(5,$/%86
,17(5)$&(
6(/(&725
6&/
,)6
,&%86
,17(5)$&(
3&)
538
76
7(03
7(03(5$785(
6(1625
&RQWUROB
K
&RQWUROB
K
&RQWUROB
K
6HFRQGV
K
0LQXWHV
K
+RXUV
K
'D\V
K
:HHNGD\V
K
0RQWKV
K
<HDUV
K
6HFRQGBDODUP
$K
0LQXWHBDODUP
%K
+RXUBDODUP
&K
'D\BDODUP
'K
:HHNGD\BDODUP
(K
&/.287BFWO
)K
:DWFKGJBWLPBFWO
K
:DWFKGJBWLPBYDO
K
7LPHVWSBFWO
K
6HFBWLPHVWS
K
0LQBWLPHVWS
K
+RXUBWLPHVWS
K
'D\BWLPHVWS
K
0RQBWLPHVWS
K
<HDUBWLPHVWS
K
$JLQJBRIIVHW
K
,QWHUQDOBUHJ
$K
,QWHUQDOBUHJ
%K
DDD
Fig 1.
Block diagram of PCF2129
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
3 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
7. Pinning information
7.1 Pinning
6&/
6',
9''
9%$7
6'2
%%6
6'$&(
,17
,)6
76
&/.287
QF
966
QF
QF
QF
QF QF
3&)$7
QF
QF
DDM
Top view. For mechanical details, see Figure 50.
Fig 2.
Pin configuration for PCF2129AT (SO20)
6&/
9''
6',
9%$7
6'2
%%6
6'$&(
,)6
76
QF
&/.287
QF
966
3&)7
,17
QF
QF
DDD
Top view. For mechanical details, see Figure 50.
Fig 3.
Pin configuration for PCF2129T (SO16)
DDD
Fig 4.
PCF2129
Product data sheet
Position of the stubs from the package assembly process
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
4 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
After lead forming and cutting, there remain stubs from the package assembly process.
These stubs are present at the edge of the package as illustrated in Figure 4. The stubs
are at an electrical potential. To avoid malfunction of the PCF2129, it has to be ensured
that they are not shorted with another electrical potential (e.g. by condensation).
7.2 Pin description
Table 4.
Pin description of PCF2129
Input or input/output pins must always be at a defined level (VSS or VDD) unless otherwise specified.
Symbol
Pin
Description
PCF2129AT
PCF2129T
SCL
1
1
combined serial clock input for both I2C-bus and SPI-bus
SDI
2
2
serial data input for SPI-bus
connect to pin VSS if I2C-bus is selected
SDO
3
3
serial data output for SPI-bus, push-pull
SDA/CE
4
4
combined serial data input and output for the I2C-bus and
chip enable input (active LOW) for the SPI-bus
IFS
5
5
interface selector input
connect to pin VSS to select the SPI-bus
connect to pin BBS to select the I2C-bus
TS
6
6
timestamp input (active LOW) with 200 k internal pull-up
resistor (RPU)
CLKOUT
7
7
clock output (open-drain)
VSS
8
8
ground supply voltage
n.c.
9 to 16
9 to 12
not connected; do not connect; do not use as feed through
INT
17
13
interrupt output (open-drain; active LOW)
BBS
18
14
output voltage (battery backed)
VBAT
19
15
battery supply voltage (backup)
VDD
20
16
supply voltage
connect to VSS if battery switch over is not used
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
5 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
8. Functional description
The PCF2129 is a Real Time Clock (RTC) and calendar with an on-chip Temperature
Compensated Crystal (Xtal) Oscillator (TCXO) and a 32.768 kHz quartz crystal integrated
into the same package (see Section 8.3.3).
Address and data are transferred by a selectable 400 kHz Fast-mode I2C-bus or a 3 line
SPI-bus with separate data input and output (see Section 9). The maximum speed of the
SPI-bus is 6.5 Mbit/s.
The PCF2129 has a backup battery input pin and backup battery switch-over circuit which
monitors the main power supply. The backup battery switch-over circuit automatically
switches to the backup battery when a power failure condition is detected (see
Section 8.5.1). Accurate timekeeping is maintained even when the main power supply is
interrupted.
A battery low detection circuit monitors the status of the battery (see Section 8.5.2). When
the battery voltage drops below a certain threshold value, a flag is set to indicate that the
battery must be replaced soon. This ensures the integrity of the data during periods of
battery backup.
8.1 Register overview
The PCF2129 contains an auto-incrementing address register: the built-in address
register will increment automatically after each read or write of a data byte up to the
register 1Bh. After register 1Bh, the auto-incrementing will wrap around to address 00h
(see Figure 5).
DGGUHVVUHJLVWHU
K
K
K
DXWRLQFUHPHQW
K
K
$K
%K
Fig 5.
ZUDSDURXQG
DDM
Handling address registers
• The first three registers (memory address 00h, 01h, and 02h) are used as control
registers (see Section 8.2).
• The memory addresses 03h through to 09h are used as counters for the clock
function (seconds up to years). The date is automatically adjusted for months with
fewer than 31 days, including corrections for leap years. The clock can operate in
12-hour mode with an AM/PM indication or in 24-hour mode (see Section 8.8).
• The registers at addresses 0Ah through 0Eh define the alarm function. It can be
selected that an interrupt is generated when an alarm event occurs (see Section 8.9).
• The register at address 0Fh defines the temperature measurement period and the
clock out mode. The temperature measurement can be selected from every 4 minutes
(default) down to every 30 seconds (see Table 14). CLKOUT frequencies of
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
6 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
32.768 kHz (default) down to 1 Hz for use as system clock, microcontroller clock, and
so on, can be chosen (see Table 15).
• The registers at addresses 10h and 11h are used for the watchdog timer functions.
The watchdog timer has four selectable source clocks allowing for timer periods from
less than 1 ms to greater than 4 hours (see Table 52). An interrupt is generated when
the watchdog times out.
• The registers at addresses 12h to 18h are used for the timestamp function. When the
trigger event happens, the actual time is saved in the timestamp registers (see
Section 8.11).
• The register at address 19h is used for the correction of the crystal aging effect (see
Section 8.4.1).
• The registers at addresses 1Ah and 1Bh are for internal use only.
• The registers Seconds, Minutes, Hours, Days, Months, and Years are all coded in
Binary Coded Decimal (BCD) format to simplify application use. Other registers are
either bit-wise or standard binary.
When one of the RTC registers is written or read, the content of all counters is temporarily
frozen. This prevents a faulty writing or reading of the clock and calendar during a carry
condition (see Section 8.8.8).
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
7 of 86
xxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxx x x x xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxx xx xx xxxxx
xxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxx xxxxxx xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxx x x
xxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxx xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxx
xxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxxx xxx
NXP Semiconductors
PCF2129
Product data sheet
Table 5.
Register overview
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as T must always be written with logic 0. Bits labeled as X are undefined at
power-on and unchanged by subsequent resets.
Address
Register name
Bit
7
6
5
4
3
2
1
Reset value
Reference
0
Control registers
00h
Control_1
EXT_
TEST
T
STOP
TSF1
POR_
OVRD
12_24
MI
SI
0000 1000
Table 7 on page 10
01h
Control_2
MSF
WDTF
TSF2
AF
T
TSIE
AIE
T
0000 0000
Table 9 on page 11
02h
Control_3
BTSE
BF
BLF
BIE
BLIE
0000 0000
Table 11 on page 12
PWRMNG[2:0]
Time and date registers
Seconds
OSF
SECONDS (0 to 59)
1XXX XXXX
Table 22 on page 25
04h
Minutes
-
MINUTES (0 to 59)
- XXX XXXX
Table 25 on page 26
05h
Hours
-
-
- - XX XXXX
Table 27 on page 27
06h
Days
-
-
07h
Weekdays
-
-
-
08h
Months
-
-
-
09h
Years
AMPM
HOURS (1 to 12) in 12-hour mode
HOURS (0 to 23) in 24-hour mode
- - XX XXXX
DAYS (1 to 31)
- - XX XXXX
Table 29 on page 27
- - - - - XXX
Table 31 on page 28
- - - X XXXX
Table 34 on page 29
YEARS (0 to 99)
XXXX XXXX
Table 37 on page 30
-
-
WEEKDAYS (0 to 6)
MONTHS (1 to 12)
Alarm registers
0Ah
Second_alarm
AE_S
SECOND_ALARM (0 to 59)
1XXX XXXX
Table 39 on page 33
0Bh
Minute_alarm
AE_M
MINUTE_ALARM (0 to 59)
1XXX XXXX
Table 41 on page 33
0Ch
Hour_alarm
AE_H
1 - XX XXXX
Table 43 on page 34
-
Day_alarm
AE_D
-
0Eh
Weekday_alarm
AE_W
-
HOUR_ALARM (1 to 12) in 12-hour mode
HOUR_ALARM (0 to 23) in 24-hour mode
1 - XX XXXX
DAY_ALARM (1 to 31)
1 - XX XXXX
Table 45 on page 34
-
-
-
WEEKDAY_ALARM (0 to 6)
1 - - - - XXX
Table 47 on page 35
OTPR
-
-
COF[2:0]
00X - - 000
Table 13 on page 12
TI_TP
-
-
000 - - - 11
Table 49 on page 36
XXXX XXXX
Table 51 on page 36
00 - X XXXX
Table 58 on page 41
CLKOUT control register
0Fh
CLKOUT_ctl
TCR[1:0]
Watchdog registers
10h
Watchdg_tim_ctl
11h
Watchdg_tim_val
WD_CD
T
-
WATCHDG_TIM_VAL[7:0]
TF[1:0]
Timestamp registers
12h
Timestp_ctl
TSM
TSOFF
-
1_O_16_TIMESTP[4:0]
PCF2129
8 of 86
© NXP Semiconductors N.V. 2014. All rights reserved.
0Dh
AMPM
Accurate RTC with integrated quartz crystal for industrial applications
Rev. 7 — 19 December 2014
All information provided in this document is subject to legal disclaimers.
03h
xxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxx x x x xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxx xx xx xxxxx
xxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxx xxxxxx xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxx x x
xxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxx xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxx
xxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxxx xxx
Register name
Bit
13h
Sec_timestp
-
14h
Min_timestp
-
15h
Hour_timestp
-
-
16h
Day_timestp
-
-
17h
Mon_timestp
-
-
18h
Year_timestp
7
6
5
Reset value
Reference
SECOND_TIMESTP (0 to 59)
- XXX XXXX
Table 60 on page 41
MINUTE_TIMESTP (0 to 59)
- XXX XXXX
Table 62 on page 42
- - XX XXXX
Table 64 on page 42
4
AMPM
3
2
1
0
HOUR_TIMESTP (1 to 12) in 12-hour mode
Rev. 7 — 19 December 2014
All information provided in this document is subject to legal disclaimers.
HOUR_TIMESTP (0 to 23) in 24-hour mode
- - XX XXXX
DAY_TIMESTP (1 to 31)
- - XX XXXX
Table 66 on page 43
- - - X XXXX
Table 68 on page 43
XXXX XXXX
Table 70 on page 43
- - - - 1000
Table 17 on page 14
-
MONTH_TIMESTP (1 to 12)
YEAR_TIMESTP (0 to 99)
Aging offset register
19h
Aging_offset
-
-
-
-
AO[3:0]
Internal registers
1Ah
Internal_reg
-
-
-
-
-
-
-
-
---- ----
-
1Bh
Internal_reg
-
-
-
-
-
-
-
-
---- ----
-
PCF2129
9 of 86
© NXP Semiconductors N.V. 2014. All rights reserved.
Accurate RTC with integrated quartz crystal for industrial applications
Address
NXP Semiconductors
PCF2129
Product data sheet
Table 5.
Register overview …continued
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as T must always be written with logic 0. Bits labeled as X are undefined at
power-on and unchanged by subsequent resets.
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
8.2 Control registers
The first 3 registers of the PCF2129, with the addresses 00h, 01h, and 02h, are used as
control registers.
8.2.1 Register Control_1
Table 6.
Control_1 - control and status register 1 (address 00h) bit allocation
Bits labeled as T must always be written with logic 0.
Bit
Symbol
7
6
5
4
3
2
1
0
EXT_
TEST
T
STOP
TSF1
POR_
OVRD
12_24
MI
SI
0
0
0
0
1
0
0
0
Reset
value
Table 7.
Control_1 - control and status register 1 (address 00h) bit description
Bits labeled as T must always be written with logic 0.
Bit
Symbol
Value
Description
Reference
7
EXT_TEST
0
normal mode
Section 8.13
1
external clock test mode
6
T
0
unused
-
5
STOP
0
RTC source clock runs
Section 8.14
1
RTC clock is stopped;
RTC divider chain flip-flops are asynchronously
set logic 0;
CLKOUT at 32.768 kHz, 16.384 kHz, or
8.192 kHz is still available
4
TSF1
0
no timestamp interrupt generated
Section 8.11.1
1
flag set when TS input is driven to an intermediate
level between power supply and ground;
flag must be cleared to clear interrupt
3
POR_OVRD
0
Power-On Reset Override (PORO) facility disabled; Section 8.7.2
1
Power-On Reset Override (PORO) sequence
reception enabled
0
24-hour mode selected
1
12-hour mode selected
Table 27,
Table 43,
Table 64
0
minute interrupt disabled
Section 8.12.1
1
minute interrupt enabled
0
second interrupt disabled
1
second interrupt enabled
set logic 0 for normal operation
2
1
0
12_24
MI
SI
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
10 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
8.2.2 Register Control_2
Table 8.
Control_2 - control and status register 2 (address 01h) bit allocation
Bits labeled as T must always be written with logic 0.
Bit
Symbol
7
6
5
4
3
2
1
0
MSF
WDTF
TSF2
AF
T
TSIE
AIE
T
0
0
0
0
0
0
0
0
Reset
value
Table 9.
Control_2 - control and status register 2 (address 01h) bit description
Bits labeled as T must always be written with logic 0.
Bit
Symbol
Value
Description
Reference
7
MSF
0
no minute or second interrupt generated
Section 8.12
1
flag set when minute or second interrupt generated;
flag must be cleared to clear interrupt
6
WDTF
0
no watchdog timer interrupt or reset generated
1
flag set when watchdog timer interrupt or reset
generated;
Section 8.12.3
flag cannot be cleared by command (read-only)
5
TSF2
0
no timestamp interrupt generated
Section 8.11.1
1
flag set when TS input is driven to ground;
flag must be cleared to clear interrupt
4
AF
0
no alarm interrupt generated
1
flag set when alarm triggered;
Section 8.9.6
flag must be cleared to clear interrupt
3
T
2
TSIE
1
0
AIE
T
PCF2129
Product data sheet
0
unused
Section 8.12.5
0
no interrupt generated from timestamp flag
1
interrupt generated when timestamp flag set
0
no interrupt generated from the alarm flag
1
interrupt generated when alarm flag set
0
unused
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
Section 8.12.4
-
© NXP Semiconductors N.V. 2014. All rights reserved.
11 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
8.2.3 Register Control_3
Table 10.
Control_3 - control and status register 3 (address 02h) bit allocation
Bit
7
6
Symbol
PWRMNG[2:0]
Reset
value
Table 11.
5
0
0
0
4
3
2
1
0
BTSE
BF
BLF
BIE
BLIE
0
0
0
0
0
Control_3 - control and status register 3 (address 02h) bit description
Bit
Symbol
Value
Description
Reference
7 to 5
PWRMNG[2:0]
see
Table 19
control of the battery switch-over, battery low
detection, and extra power fail detection functions
Section 8.5
4
BTSE
0
no timestamp when battery switch-over occurs
Section 8.11.4
1
time-stamped when battery switch-over occurs
0
no battery switch-over interrupt generated
1
flag set when battery switch-over occurs;
3
BF
Section 8.5.1
and
Section 8.11.4
flag must be cleared to clear interrupt
2
BLF
0
battery status ok;
Section 8.5.2
no battery low interrupt generated
1
battery status low;
flag cannot be cleared by command
1
0
BIE
BLIE
0
no interrupt generated from the battery flag (BF)
1
interrupt generated when BF is set
0
no interrupt generated from battery low flag (BLF)
1
interrupt generated when BLF is set
Section 8.12.6
Section 8.12.7
8.3 Register CLKOUT_ctl
Table 12. CLKOUT_ctl - CLKOUT control register (address 0Fh) bit allocation
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as X are undefined at power-on and
unchanged by subsequent resets.
Bit
7
Symbol
6
5
TCR[1:0]
Reset
value
0
0
4
3
OTPR
-
-
X
-
-
2
1
0
COF[2:0]
0
0
0
Table 13. CLKOUT_ctl - CLKOUT control register (address 0Fh) bit description
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as X are undefined at power-on and
unchanged by subsequent resets.
Bit
Symbol
Value
Description
7 to 6
TCR[1:0]
see Table 14
temperature measurement period
5
OTPR
0
no OTP refresh
1
OTP refresh performed
4 to 3
-
-
unused
2 to 0
COF[2:0]
see Table 15
CLKOUT frequency selection
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
12 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
8.3.1 Temperature compensated crystal oscillator
The frequency of tuning fork quartz crystal oscillators is temperature-dependent. In the
PCF2129, the frequency deviation caused by temperature variation is corrected by
adjusting the load capacitance of the crystal oscillator.
The load capacitance is changed by switching between two load capacitance values using
a modulation signal with a programmable duty cycle. In order to compensate the spread of
the quartz parameters every chip is factory calibrated.
The frequency accuracy can be evaluated by measuring the frequency of the square
wave signal available at the output pin CLKOUT. However, the selection of
fCLKOUT = 32.768 kHz (default value) leads to inaccurate measurements. Accurate
frequency measurement occurs when fCLKOUT = 16.384 kHz or lower is selected (see
Table 15).
8.3.1.1
Temperature measurement
The PCF2129 has a temperature sensor circuit used to perform the temperature
compensation of the frequency. The temperature is measured immediately after power-on
and then periodically with a period set by the temperature conversion rate TCR[1:0] in the
register CLKOUT_ctl.
Table 14.
Temperature measurement period
TCR[1:0]
Temperature measurement period
[1]
00
4 min
01
2 min
10
1 min
11
30 seconds
[1]
Default value.
8.3.2 OTP refresh
Each IC is calibrated during production and testing of the device. The calibration
parameters are stored on EPROM cells called One Time Programmable (OTP) cells. It is
recommended to process an OTP refresh once after the power is up and the oscillator is
operating stable. The OTP refresh takes less than 100 ms to complete.
To perform an OTP refresh, bit OTPR has to be cleared (set to logic 0) and then set to
logic 1 again.
8.3.3 Clock output
A programmable square wave is available at pin CLKOUT. Operation is controlled by the
COF[2:0] control bits in register CLKOUT_ctl. Frequencies of 32.768 kHz (default) down
to 1 Hz can be generated for use as system clock, microcontroller clock, charge pump
input, or for calibrating the oscillator.
CLKOUT is an open-drain output and enabled at power-on. When disabled, the output is
high-impedance.
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
13 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
Table 15.
CLKOUT frequency selection
CLKOUT frequency (Hz)
Typical duty cycle[1]
32768
60 : 40 to 40 : 60
001
16384
50 : 50
010
8192
50 : 50
011
4096
50 : 50
100
2048
50 : 50
101
1024
50 : 50
110
1
50 : 50
111
CLKOUT = high-Z
-
COF[2:0]
[2][3]
000
[1]
Duty cycle definition: % HIGH-level time : % LOW-level time.
[2]
Default value.
[3]
The specified accuracy of the RTC can be only achieved with CLKOUT frequencies not equal to
32.768 kHz or if CLKOUT is disabled.
The duty cycle of the selected clock is not controlled, however, due to the nature of the
clock generation all but the 32.768 kHz frequencies are 50 : 50.
8.4 Register Aging_offset
Table 16. Aging_offset - crystal aging offset register (address 19h) bit allocation
Bit positions labeled as - are not implemented and return 0 when read.
Bit
7
6
5
4
Symbol
-
-
-
-
Reset
value
-
-
-
-
3
2
1
0
0
0
AO[3:0]
1
0
Table 17. Aging_offset - crystal aging offset register (address 19h) bit description
Bit positions labeled as - are not implemented and return 0 when read.
Bit
Symbol
Value
Description
7 to 4
-
-
unused
3 to 0
AO[3:0]
see Table 18
aging offset value
8.4.1 Crystal aging correction
The PCF2129 has an offset register Aging_offset to correct the crystal aging effects2.
The accuracy of the frequency of a quartz crystal depends on its aging. The aging offset
adds an adjustment, positive or negative, in the temperature compensation circuit which
allows correcting the aging effect.
At 25 C, the aging offset bits allow a frequency correction of typically 1 ppm per AO[3:0]
value, from 7 ppm to +8 ppm.
2.
For further information, refer to the application note Ref. 3 “AN11186”.
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
14 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
Table 18.
Frequency correction at 25C, typical
AO[3:0]
Decimal
Binary
0
0000
+8
1
0001
+7
2
0010
+6
3
0011
+5
4
0100
+4
5
0101
+3
6
0110
+2
7
0111
Product data sheet
+1
[1]
0
8
1000
9
1001
1
10
1010
2
11
1011
3
12
1100
4
13
1101
5
14
1110
6
15
1111
7
[1]
PCF2129
ppm
Default value.
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
15 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
8.5 Power management functions
The PCF2129 has two power supplies:
VDD — the main power supply
VBAT — the battery backup supply
Internally, the PCF2129 is operating with the internal operating voltage Voper(int) which is
also available as VBBS on the battery backed output voltage pin, BBS. Depending on the
condition of the main power supply and the selected power management function,
Voper(int) is either on the potential of VDD or VBAT (see Section 8.5.3).
Two power management functions are implemented:
Battery switch-over function — monitoring the main power supply VDD and switching to
VBAT in case a power fail condition is detected (see Section 8.5.1).
Battery low detection function — monitoring the status of the battery, VBAT (see
Section 8.5.2).
The power management functions are controlled by the control bits PWRMNG[2:0] (see
Table 19) in register Control_3 (see Table 11):
Table 19.
Power management control bit description
PWRMNG[2:0]
Function
[1]
000
battery switch-over function is enabled in standard mode;
battery low detection function is enabled
001
battery switch-over function is enabled in standard mode;
battery low detection function is disabled
010
battery switch-over function is enabled in standard mode;
battery low detection function is disabled
011
battery switch-over function is enabled in direct switching mode;
battery low detection function is enabled
100
battery switch-over function is enabled in direct switching mode;
battery low detection function is disabled
101
battery switch-over function is enabled in direct switching mode;
battery low detection function is disabled
[2]
111
battery switch-over function is disabled, only one power supply
(VDD);
battery low detection function is disabled
PCF2129
Product data sheet
[1]
Default value.
[2]
When the battery switch-over function is disabled, the PCF2129 works only with the power supply VDD.
VBAT must be put to ground and the battery low detection function is disabled.
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
16 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
8.5.1 Battery switch-over function
The PCF2129 has a backup battery switch-over circuit which monitors the main power
supply VDD. When a power failure condition is detected, it automatically switches to the
backup battery.
One of two operation modes can be selected:
Standard mode — the power failure condition happens when:
VDD < VBAT AND VDD < Vth(sw)bat
Vth(sw)bat is the battery switch threshold voltage. Typical value is 2.5 V. The battery
switch-over in standard mode works only for VDD > 2.5 V
Direct switching mode — the power failure condition happens when VDD < VBAT. Direct
switching from VDD to VBAT without requiring VDD to drop below Vth(sw)bat
When a power failure condition occurs and the power supply switches to the battery, the
following sequence occurs:
1. The battery switch flag BF (register Control_3) is set logic 1.
2. An interrupt is generated if the control bit BIE (register Control_3) is enabled
(see Section 8.12.6).
3. If the control bit BTSE (register Control_3) is logic 1, the timestamp registers store the
time and date when the battery switch occurred (see Section 8.11.4).
4. The battery switch flag BF is cleared by command; it must be cleared to clear the
interrupt.
The interface is disabled in battery backup operation:
• Interface inputs are not recognized, preventing extraneous data being written to the
device
• Interface outputs are high-impedance
For further information about I2C-bus communication and battery backup operation, see
Section 9.3 on page 56.
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
17 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
8.5.1.1
Standard mode
If VDD > VBAT OR VDD > Vth(sw)bat: Voper(int) is at VDD potential.
If VDD < VBAT AND VDD < Vth(sw)bat: Voper(int) is at VBAT potential.
EDFNXSEDWWHU\RSHUDWLRQ
9''
9RSHULQW
9%$7
9RSHULQW
LQWHUQDORSHUDWLQJYROWDJH9RSHULQW
9WKVZEDW
9
9'' 9
%)
,17
FOHDUHGYLDLQWHUIDFH
DDM
Vth(sw)bat is the battery switch threshold voltage. Typical value is 2.5 V. In standard mode, the
battery switch-over works only for VDD > 2.5 V.
VDD may be lower than VBAT (for example VDD = 3 V, VBAT = 4.1 V).
Fig 6.
PCF2129
Product data sheet
Battery switch-over behavior in standard mode with bit BIE set logic 1 (enabled)
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
18 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
8.5.1.2
Direct switching mode
If VDD > VBAT: Voper(int) is at VDD potential.
If VDD < VBAT: Voper(int) is at VBAT potential.
The direct switching mode is useful in systems where VDD is always higher than VBAT.
This mode is not recommended if the VDD and VBAT values are similar (for example,
VDD = 3.3 V, VBAT 3.0 V). In direct switching mode, the power consumption is reduced
compared to the standard mode because the monitoring of VDD and Vth(sw)bat is not
performed.
EDFNXSEDWWHU\RSHUDWLRQ
9''
9RSHULQW
9%$7
9RSHULQW
LQWHUQDORSHUDWLQJYROWDJH9RSHULQW
9WKVZEDW
9
9'' 9
%)
,17
FOHDUHGYLDLQWHUIDFH
DDM
Fig 7.
8.5.1.3
Battery switch-over behavior in direct switching mode with bit BIE set logic 1
(enabled)
Battery switch-over disabled: only one power supply (VDD)
When the battery switch-over function is disabled:
•
•
•
•
PCF2129
Product data sheet
The power supply is applied on the VDD pin
The VBAT pin must be connected to ground
Voper(int) is at VDD potential
The battery flag (BF) is always logic 0
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
19 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
8.5.1.4
Battery switch-over architecture
The architecture of the battery switch-over circuit is shown in Figure 8.
FRPSDUDWRUV
ORJLF
VZLWFKHV
9''
9WKVZEDW
9''
9RSHULQW
/2*,&
9WKVZEDW
9%$7
9%$7
DDJ
Fig 8.
Battery switch-over circuit, simplified block diagram
Voper(int) is at VDD or VBAT potential.
Remark: It has to be assured that there are decoupling capacitors on the pins VDD, VBAT,
and BBS.
8.5.2 Battery low detection function
The PCF2129 has a battery low detection circuit which monitors the status of the battery
VBAT.
When VBAT drops below the threshold value Vth(bat)low (typically 2.5 V), the BLF flag
(register Control_3) is set to indicate that the battery is low and that it must be replaced.
Monitoring of the battery voltage also occurs during battery operation.
An unreliable battery cannot prevent that the supply voltage drops below Vlow (typical
1.2 V) and with that the data integrity gets lost. (For further information about Vlow see
Section 8.6.)
When VBAT drops below the threshold value Vth(bat)low, the following sequence occurs (see
Figure 9):
1. The battery low flag BLF is set logic 1.
2. An interrupt is generated if the control bit BLIE (register Control_3) is enabled
(see Section 8.12.7).
3. The flag BLF remains logic 1 until the battery is replaced. BLF cannot be cleared by
command. It is automatically cleared by the battery low detection circuit when the
battery is replaced or when the voltage rises again above the threshold value. This
could happen if a super capacitor is used as a backup source and the main power is
applied again.
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
20 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
9'' 9RSHULQW
LQWHUQDORSHUDWLQJYROWDJH9RSHULQW
9%$7
9WKEDWORZ
9
9%$7
%/)
,17
DDM
Fig 9.
Battery low detection behavior with bit BLIE set logic 1 (enabled)
8.5.3 Battery backup supply
The VBBS voltage on the output pin BBS is at the same potential as the internal operating
voltage Voper(int), depending on the selected battery switch-over function mode:
Table 20.
Output pin BBS
Battery switch-over function
mode
Conditions
Potential of
Voper(int) and
VBBS
standard
VDD > VBAT OR VDD > Vth(sw)bat
VDD
VDD < VBAT AND VDD < Vth(sw)bat
VBAT
direct switching
VDD > VBAT
VDD
VDD < VBAT
VBAT
disabled
only VDD available,
VBAT must be put to ground
VDD
The output pin BBS can be used as a supply for external devices with battery backup
needs, such as SRAM (see Ref. 3 “AN11186”). For this case, Figure 10 shows the typical
driving capability when VBBS is driven from VDD.
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
21 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
DDM
9%%6 9''
P9
9'' 9
9'' 9
9'' 9
,%%6P$
Fig 10. Typical driving capability of VBBS: (VBBS VDD) with respect to the output load
current IBBS
8.6 Oscillator stop detection function
The PCF2129 has an on-chip oscillator detection circuit which monitors the status of the
oscillation: whenever the oscillation stops, a reset occurs and the oscillator stop flag OSF
(in register Seconds) is set logic 1.
• Power-on:
a. The oscillator is not running, the chip is in reset (OSF is logic 1).
b. When the oscillator starts running and is stable after power-on, the chip exits from
reset.
c. The flag OSF is still logic 1 and can be cleared (OSF set logic 0) by command.
• Power supply failure:
a. When the power supply of the chip drops below a certain value (Vlow), typically
1.2 V, the oscillator stops running and a reset occurs.
b. When the power supply returns to normal operation, the oscillator starts running
again, the chip exits from reset.
c. The flag OSF is still logic 1 and can be cleared (OSF set logic 0) by command.
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
22 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
9''
9RSHULQW
9''
9RSHULQW
9%$7
9%$7
9WKVZEDW
9
9''
9''
EDWWHU\GLVFKDUJH
9ORZ
9
9RSHULQW
9%$7
966
966
26)
DDM
(1) Theoretical state of the signals since there is no power.
(2) The oscillator stop flag (OSF), set logic 1, indicates that the oscillation has stopped and a reset has
occurred since the flag was last cleared (OSF set logic 0). In this case, the integrity of the clock
information is not guaranteed. The OSF flag is cleared by command.
Fig 11. Power failure event due to battery discharge: reset occurs
8.7 Reset function
The PCF2129 has a Power-On Reset (POR) and a Power-On Reset Override (PORO)
function implemented.
8.7.1 Power-On Reset (POR)
The POR is active whenever the oscillator is stopped. The oscillator is considered to be
stopped during the time between power-on and stable crystal resonance (see Figure 12).
This time may be in the range of 200 ms to 2 s depending on temperature and supply
voltage. Whenever an internal reset occurs, the oscillator stop flag is set (OSF set
logic 1).
The OTP refresh (see Section 8.3.2 on page 13) should ideally be executed as the first
instruction after start-up and also after a reset due to an oscillator stop.
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
23 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
FKLSLQUHVHW
FKLSQRWLQUHVHW
FKLSIXOO\RSHUDWLYH
&/.287
DYDLODEOH
9''
RVFLOODWLRQ
LQWHUQDO
UHVHW
2735
W
DDD
Fig 12. Dependency between POR and oscillator
After POR, the following mode is entered:
•
•
•
•
•
32.768 kHz CLKOUT active
Power-On Reset Override (PORO) available to be set
24-hour mode is selected
Battery switch-over is enabled
Battery low detection is enabled
The register values after power-on are shown in Table 5 on page 8.
8.7.2 Power-On Reset Override (PORO)
The POR duration is directly related to the crystal oscillator start-up time. Due to the long
start-up times experienced by these types of circuits, a mechanism has been built in to
disable the POR and therefore speed up the on-board test of the device.
26&,//$725
6&/
6'$&(
5(6(7
29(55,'(
RVFVWRSSHG
VWRSSHG UXQQLQJ
UHVHW
RYHUULGHLQDFWLYH
RYHUULGHDFWLYH
&/($5
325B295'
FOHDURYHUULGHPRGH
RYHUULGHSRVVLEOH
DDM
Fig 13. Power-On Reset (POR) system
The setting of the PORO mode requires that POR_OVRD in register Control_1 is set
logic 1 and that the signals at the interface pins SDA/CE and SCL are toggled as
illustrated in Figure 14. All timings shown are required minimum.
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
24 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
SRZHUXS
PV
PLQLPXPQV
PLQLPXPQV
6'$&(
6&/
UHVHWRYHUULGH
DDM
Fig 14. Power-On Reset Override (PORO) sequence, valid for both I2C-bus and SPI-bus
Once the override mode is entered, the device is immediately released from the reset
state and the set-up operation can commence.
The PORO mode is cleared by writing logic 0 to POR_OVRD. POR_OVRD must be
logic 1 before a re-entry into the override mode is possible. Setting POR_OVRD logic 0
during normal operation has no effect except to prevent accidental entry into the PORO
mode.
8.8 Time and date function
Most of these registers are coded in the Binary Coded Decimal (BCD) format.
8.8.1 Register Seconds
Table 21. Seconds - seconds and clock integrity register (address 03h) bit allocation
Bits labeled as X are undefined at power-on and unchanged by subsequent resets.
Bit
7
Symbol
6
5
4
OSF
Reset
value
1
3
2
1
0
X
X
X
SECONDS (0 to 59)
X
X
X
X
Table 22. Seconds - seconds and clock integrity register (address 03h) bit description
Bits labeled as X are undefined at power-on and unchanged by subsequent resets.
Bit
Symbol
7
OSF
Value
Place value Description
0
-
clock integrity is guaranteed
1
-
clock integrity is not guaranteed:
oscillator has stopped and chip reset has occurred
since flag was last cleared
6 to 4
SECONDS
3 to 0
PCF2129
Product data sheet
0 to 5
ten’s place
0 to 9
unit place
actual seconds coded in BCD format
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
25 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
Table 23.
Seconds coded in BCD format
Seconds
value in
decimal
Upper-digit (ten’s place)
Digit (unit place)
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
00
0
0
0
0
0
0
0
01
0
0
0
0
0
0
1
02
0
0
0
0
0
1
0
:
:
:
:
:
:
:
:
09
0
0
0
1
0
0
1
10
0
0
1
0
0
0
0
:
:
:
:
:
:
:
:
58
1
0
1
1
0
0
0
59
1
0
1
1
0
0
1
8.8.2 Register Minutes
Table 24. Minutes - minutes register (address 04h) bit allocation
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as X are undefined at power-on and
unchanged by subsequent resets.
Bit
7
Symbol
-
Reset
value
-
6
5
4
3
2
1
0
X
X
X
MINUTES (0 to 59)
X
X
X
X
Table 25. Minutes - minutes register (address 04h) bit description
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as X are undefined at power-on and
unchanged by subsequent resets.
Bit
Symbol
Value
Place value Description
7
-
-
-
unused
6 to 4
MINUTES
0 to 5
ten’s place
actual minutes coded in BCD format
0 to 9
unit place
3 to 0
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
26 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
8.8.3 Register Hours
Table 26. Hours - hours register (address 05h) bit allocation
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as X are undefined at power-on and
unchanged by subsequent resets.
Bit
7
6
5
Symbol
-
-
AMPM
4
3
2
1
0
HOURS (1 to 12) in 12-hour mode
HOURS (0 to 23) in 24-hour mode
Reset
value
-
-
X
X
X
X
X
X
Table 27. Hours - hours register (address 05h) bit description
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as X are undefined at power-on and
unchanged by subsequent resets.
Bit
Symbol
Value
Place value Description
7 to 6
-
-
-
unused
-
indicates AM
12-hour
mode[1]
5
AMPM
0
1
-
indicates PM
4
HOURS
0 to 1
ten’s place
0 to 9
unit place
actual hours coded in BCD format when in 12-hour
mode
0 to 2
ten’s place
0 to 9
unit place
3 to 0
24-hour
mode[1]
5 to 4
HOURS
3 to 0
[1]
actual hours coded in BCD format when in 24-hour
mode
Hour mode is set by the bit 12_24 in register Control_1 (see Table 7).
8.8.4 Register Days
Table 28. Days - days register (address 06h) bit allocation
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as X are undefined at power-on and
unchanged by subsequent resets.
Bit
7
6
Symbol
-
-
Reset
value
-
-
Table 29.
5
4
3
2
X
X
X
X
0
X
X
Days - days register (address 06h) bit description
Bit
Symbol
Value
Place value Description
7 to 6
-
-
-
unused
5 to 4
DAYS[1]
0 to 3
ten’s place
actual day coded in BCD format
0 to 9
unit place
3 to 0
[1]
1
DAYS (1 to 31)
If the year counter contains a value which is exactly divisible by 4, including the year 00, the RTC compensates for leap years by adding
a 29th day to February.
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
27 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
8.8.5 Register Weekdays
Table 30. Weekdays - weekdays register (address 07h) bit allocation
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as X are undefined at power-on and
unchanged by subsequent resets.
Bit
7
6
5
4
3
Symbol
-
-
-
-
-
Reset
value
-
-
-
-
-
2
1
0
WEEKDAYS (0 to 6)
X
X
X
Table 31. Weekdays - weekdays register (address 07h) bit description
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as X are undefined at power-on and
unchanged by subsequent resets.
Bit
Symbol
Value
Description
7 to 3
-
-
unused
2 to 0
WEEKDAYS
0 to 6
actual weekday value, see Table 32
Although the association of the weekdays counter to the actual weekday is arbitrary, the
PCF2129 assumes that Sunday is 000 and Monday is 001 for the purpose of determining
the increment for calendar weeks.
Table 32.
Weekday assignments
Day[1]
2
1
0
Sunday
0
0
0
Monday
0
0
1
Tuesday
0
1
0
Wednesday
0
1
1
Thursday
1
0
0
Friday
1
0
1
Saturday
1
1
0
[1]
PCF2129
Product data sheet
Bit
Definition may be reassigned by the user.
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
28 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
8.8.6 Register Months
Table 33. Months - months register (address 08h) bit allocation
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as X are undefined at power-on and
unchanged by subsequent resets.
Bit
7
6
5
Symbol
-
-
-
Reset
value
-
-
-
4
3
2
1
0
X
X
MONTHS (1 to 12)
X
X
X
Table 34. Months - months register (address 08h) bit description
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as X are undefined at power-on and
unchanged by subsequent resets.
Bit
Symbol
Value
Place value Description
7 to 5
-
-
-
unused
4
MONTHS
0 to 1
ten’s place
actual month coded in BCD format, see Table 35
0 to 9
unit place
3 to 0
Table 35.
Month
PCF2129
Product data sheet
Month assignments in BCD format
Upper-digit
(ten’s place)
Digit (unit place)
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
January
0
0
0
0
1
February
0
0
0
1
0
March
0
0
0
1
1
April
0
0
1
0
0
May
0
0
1
0
1
June
0
0
1
1
0
July
0
0
1
1
1
August
0
1
0
0
0
September
0
1
0
0
1
October
1
0
0
0
0
November
1
0
0
0
1
December
1
0
0
1
0
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
29 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
8.8.7 Register Years
Table 36. Years - years register (address 09h) bit allocation
Bits labeled as X are undefined at power-on and unchanged by subsequent resets.
Bit
7
6
5
X
X
X
Symbol
4
3
2
1
0
X
X
X
YEARS (0 to 99)
Reset
value
X
X
Table 37. Years - years register (address 09h) bit description
Bits labeled as X are undefined at power-on and unchanged by subsequent resets.
Bit
Symbol
Value
Place value Description
7 to 4
YEARS
0 to 9
ten’s place
0 to 9
unit place
3 to 0
actual year coded in BCD format
8.8.8 Setting and reading the time
Figure 15 shows the data flow and data dependencies starting from the 1 Hz clock tick.
During read/write operations, the time counting circuits (memory locations 03h through
09h) are blocked.
This prevents
• Faulty reading of the clock and calendar during a carry condition
• Incrementing the time registers during the read cycle
+]WLFN
6(&21'6
0,187(6
BKRXUPRGH
+2856
/($3<($5
&$/&8/$7,21
'$<6
:((.'$<
0217+6
<($56
DDI
Fig 15. Data flow of the time function
After this read/write access is completed, the time circuit is released again. Any pending
request to increment the time counters that occurred during the read/write access is
serviced. A maximum of 1 request can be stored; therefore, all accesses must be
completed within 1 second (see Figure 16).
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
30 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
WV
67$57
6/$9($''5(66
'$7$
'$7$
6723
DDD
Fig 16. Access time for read/write operations
As a consequence of this method, it is very important to make a read or write access in
one go. That is, setting or reading seconds through to years should be made in one single
access. Failing to comply with this method could result in the time becoming corrupted.
As an example, if the time (seconds through to hours) is set in one access and then in a
second access the date is set, it is possible that the time may increment between the two
accesses. A similar problem exists when reading. A roll-over may occur between reads
thus giving the minutes from one moment and the hours from the next. Therefore it is
advised to read all time and date registers in one access.
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
31 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
8.9 Alarm function
When one or more of the alarm bit fields are loaded with a valid second, minute, hour, day,
or weekday and its corresponding alarm enable bit (AE_x) is logic 0, then that information
is compared with the actual second, minute, hour, day, and weekday (see Figure 17).
H[DPSOH
FKHFNQRZVLJQDO
$(B6
$(B6 6(&21'$/$50
6(&21'7,0(
$(B0
0,187($/$50
0,187(7,0(
$(B+
+285$/$50
VHWDODUPIODJ$) +2857,0(
$(B'
'$<$/$50
'$<7,0(
$(B:
:((.'$<$/$50
DDD
:((.'$<7,0(
(1) Only when all enabled alarm settings are matching.
Fig 17. Alarm function block diagram
The generation of interrupts from the alarm function is described in Section 8.12.4.
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
32 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
8.9.1 Register Second_alarm
Table 38. Second_alarm - second alarm register (address 0Ah) bit allocation
Bits labeled as X are undefined at power-on and unchanged by subsequent resets.
Bit
Symbol
7
5
4
X
X
X
AE_S
Reset
value
Table 39.
6
1
3
2
1
0
X
X
SECOND_ALARM (0 to 59)
X
X
Second_alarm - second alarm register (address 0Ah) bit description
Bit
Symbol
Value
Place value Description
7
AE_S
0
-
second alarm is enabled
1
-
second alarm is disabled
0 to 5
ten’s place
second alarm information coded in BCD format
0 to 9
unit place
6 to 4
SECOND_ALARM
3 to 0
8.9.2 Register Minute_alarm
Table 40. Minute_alarm - minute alarm register (address 0Bh) bit allocation
Bits labeled as X are undefined at power-on and unchanged by subsequent resets.
Bit
Symbol
7
6
5
4
AE_M
Reset
value
1
3
2
1
0
X
X
MINUTE_ALARM (0 to 59)
X
X
X
X
X
Table 41. Minute_alarm - minute alarm register (address 0Bh) bit description
Bits labeled as X are undefined at power-on and unchanged by subsequent resets.
Bit
Symbol
Value
Place value Description
7
AE_M
0
-
minute alarm is enabled
1
-
minute alarm is disabled
0 to 5
ten’s place
minute alarm information coded in BCD format
0 to 9
unit place
6 to 4
MINUTE_ALARM
3 to 0
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
33 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
8.9.3 Register Hour_alarm
Table 42. Hour_alarm - hour alarm register (address 0Ch) bit allocation
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as X are undefined at power-on and
unchanged by subsequent resets.
Bit
Symbol
7
6
5
AE_H
-
AMPM
4
3
2
1
0
HOUR_ALARM (1 to 12) in 12-hour mode
HOUR_ALARM (0 to 23) in 24-hour mode
Reset
value
1
-
X
X
X
X
X
X
Table 43. Hour_alarm - hour alarm register (address 0Ch) bit description
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as X are undefined at power-on and
unchanged by subsequent resets.
Bit
Symbol
Value
Place value Description
7
AE_H
0
-
hour alarm is enabled
1
-
hour alarm is disabled
-
-
unused
0
-
indicates AM
1
-
indicates PM
0 to 1
ten’s place
0 to 9
unit place
hour alarm information coded in BCD format when in
12-hour mode
0 to 2
ten’s place
0 to 9
unit place
6
-
12-hour
5
mode[1]
AMPM
4
HOUR_ALARM
3 to 0
24-hour mode[1]
5 to 4
HOUR_ALARM
3 to 0
[1]
hour alarm information coded in BCD format when in
24-hour mode
Hour mode is set by the bit 12_24 in register Control_1.
8.9.4 Register Day_alarm
Table 44. Day_alarm - day alarm register (address 0Dh) bit allocation
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as X are undefined at power-on and
unchanged by subsequent resets.
Bit
Symbol
7
6
AE_D
-
1
-
Reset
value
5
4
3
2
1
0
X
X
DAY_ALARM (1 to 31)
X
X
X
X
Table 45. Day_alarm - day alarm register (address 0Dh) bit description
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as X are undefined at power-on and
unchanged by subsequent resets.
Bit
Symbol
Value
Place value Description
7
AE_D
0
-
day alarm is enabled
1
-
day alarm is disabled
6
-
-
-
unused
5 to 4
DAY_ALARM
0 to 3
ten’s place
day alarm information coded in BCD format
0 to 9
unit place
3 to 0
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
34 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
8.9.5 Register Weekday_alarm
Table 46. Weekday_alarm - weekday alarm register (address 0Eh) bit allocation
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as X are undefined at power-on and
unchanged by subsequent resets.
Bit
Symbol
7
6
5
4
3
2
AE_W
-
-
-
-
WEEKDAY_ALARM (0 to 6)
1
-
-
-
-
X
Reset
value
1
X
0
X
Table 47. Weekday_alarm - weekday alarm register (address 0Eh) bit description
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as X are undefined at power-on and
unchanged by subsequent resets.
Bit
Symbol
Value
Description
7
AE_W
0
weekday alarm is enabled
1
weekday alarm is disabled
6 to 3
-
-
unused
2 to 0
WEEKDAY_ALARM
0 to 6
weekday alarm information
8.9.6 Alarm flag
When all enabled comparisons first match, the alarm flag AF (register Control_2) is set.
AF remains set until cleared by command. Once AF has been cleared, it will only be set
again when the time increments to match the alarm condition once more. For clearing the
flags, see Section 8.10.5
Alarm registers which have their alarm enable bit AE_x at logic 1 are ignored.
PLQXWHVFRXQWHU
PLQXWHDODUP
$)
,17ZKHQ$,( DDI
Example where only the minute alarm is used and no other interrupts are enabled.
Fig 18. Alarm flag timing diagram
8.10 Timer functions
The PCF2129 has a watchdog timer function. The timer can be switched on and off by
using the control bit WD_CD in the register Watchdg_tim_ctl.
The watchdog timer has four selectable source clocks. It can, for example, be used to
detect a microcontroller with interrupt and reset capability which is out of control (see
Section 8.10.3)
To control the timer function and timer output, the registers Control_2, Watchdg_tim_ctl,
and Watchdg_tim_val are used.
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
35 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
8.10.1 Register Watchdg_tim_ctl
Table 48. Watchdg_tim_ctl - watchdog timer control register (address 10h) bit allocation
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as T must always be written with logic 0.
Bit
Symbol
7
6
5
4
3
2
WD_CD
T
TI_TP
-
-
-
0
0
0
-
-
-
Reset
value
1
0
TF[1:0]
1
1
Table 49. Watchdg_tim_ctl - watchdog timer control register (address 10h) bit description
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as T must always be written with logic 0.
Bit
Symbol
Value
Description
7
WD_CD
0
watchdog timer disabled
1
watchdog timer enabled;
the interrupt pin INT is activated when timed out
6
T
0
unused
5
TI_TP
0
the interrupt pin INT is configured to generate a
permanent active signal when MSF is set
1
the interrupt pin INT is configured to generate a
pulsed signal when MSF flag is set (see Figure 21)
-
unused
4 to 2
-
1 to 0
TF[1:0]
timer source clock for watchdog timer
00
4.096 kHz
01
64 Hz
10
1 Hz
11
1⁄
60
Hz
8.10.2 Register Watchdg_tim_val
Table 50. Watchdg_tim_val - watchdog timer value register (address 11h) bit allocation
Bits labeled as X are undefined at power-on and unchanged by subsequent resets.
Bit
7
6
5
4
Symbol
3
2
1
0
X
X
X
WATCHDG_TIM_VAL[7:0]
Reset
value
X
X
X
X
X
Table 51. Watchdg_tim_val - watchdog timer value register (address 11h) bit description
Bits labeled as X are undefined at power-on and unchanged by subsequent resets.
Bit
Symbol
Value
Description
7 to 0
WATCHDG_TIM_
VAL[7:0]
00 to FF
timer period in seconds:
n
TimerPeriod = -------------------------------------------------------------SourceClockFrequency
where n is the timer value
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
36 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
Table 52.
Programmable watchdog timer
TF[1:0] Timer source
clock frequency
Units
Minimum timer
period (n = 1)
Units
Maximum timer
period (n = 255)
Units
00
4.096
kHz
244
s
62.256
ms
01
64
Hz
15.625
ms
3.984
s
10
1
Hz
1
s
255
s
11
1⁄
60
Hz
60
s
15300
s
8.10.3 Watchdog timer function
The watchdog timer function is enabled or disabled by the WD_CD bit of the register
Watchdg_tim_ctl (see Table 49).
The 2 bits TF[1:0] in register Watchdg_tim_ctl determine one of the four source clock
frequencies for the watchdog timer: 4.096 kHz, 64 Hz, 1 Hz, or 1⁄60 Hz (see Table 52).
When the watchdog timer function is enabled, the 8-bit timer in register Watchdg_tim_val
determines the watchdog timer period (see Table 52).
The watchdog timer counts down from the software programmed 8-bit binary value n in
register Watchdg_tim_val. When the counter reaches 1, the watchdog timer flag WDTF
(register Control_2) is set logic 1 and an interrupt is generated.
The counter does not automatically reload.
When WD_CD is logic 0 (watchdog timer disabled) and the Microcontroller Unit (MCU)
loads a watchdog timer value n:
• the flag WDTF is reset
• INT is cleared
• the watchdog timer starts again
Loading the counter with 0 will:
• reset the flag WDTF
• clear INT
• stop the watchdog timer
Remark: WDTF is read only and cannot be cleared by command. WDTF can be cleared
by:
• loading a value in register Watchdg_tim_val
• reading of the register Control_2
Writing a logic 0 or logic 1 to WDTF has no effect.
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
37 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
0&8
ZDWFKGRJ
WLPHUYDOXH
Q Q
:'7)
,17
DDJ
Counter reached 1, WDTF is logic 1, and an interrupt is generated.
Fig 19. WD_CD set logic 1: watchdog activates an interrupt when timed out
• When the watchdog timer counter reaches 1, the watchdog timer flag WDTF is set
logic 1
• When a minute or second interrupt occurs, the minute/second flag MSF is set logic 1
(see Section 8.12.1).
8.10.4 Pre-defined timers: second and minute interrupt
PCF2129 has two pre-defined timers which are used to generate an interrupt either once
per second or once per minute (see Section 8.12.1). The pulse generator for the minute or
second interrupt operates from an internal 64 Hz clock. It is independent of the watchdog
timer. Each of these timers can be enabled by the bits SI (second interrupt) and MI
(minute interrupt) in register Control_1.
8.10.5 Clearing flags
The flags MSF, AF, and TSFx can be cleared by command. To prevent one flag being
overwritten while clearing another, a logic AND is performed during the write access. A
flag is cleared by writing logic 0 while a flag is not cleared by writing logic 1. Writing logic 1
results in the flag value remaining unchanged.
Two examples are given for clearing the flags. Clearing a flag is made by a write
command:
• Bits labeled with - must be written with their previous values
• Bits labeled with T have to be written with logic 0
• WDTF is read only and has to be written with logic 0
Repeatedly rewriting these bits has no influence on the functional behavior.
Table 53.
Register
Control_2
PCF2129
Product data sheet
Flag location in register Control_2
Bit
7
6
5
4
3
2
1
0
MSF
WDTF
TSF2
AF
T
-
-
T
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
38 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
Table 54.
Register
Control_2
Example values in register Control_2
Bit
7
6
5
4
3
2
1
0
1
0
1
1
0
0
0
0
The following tables show what instruction must be sent to clear the appropriate flag.
Table 55.
Register
Example to clear only AF (bit 4)
Bit
7
Control_2
[1]
6
1
0
1
4
0
3
2
1
0
0
0[1]
0[1]
0
3
2
1
0
0
0[1]
0[1]
0
The bits labeled as - have to be rewritten with the previous values.
Table 56.
Register
Example to clear only MSF (bit 7)
Bit
7
Control_2
[1]
5
6
0
0
5
1
4
1
The bits labeled as - have to be rewritten with the previous values.
8.11 Timestamp function
The PCF2129 has an active LOW timestamp input pin TS, internally pulled with an
on-chip pull-up resistor to Voper(int). It also has a timestamp detection circuit which can
detect two different events:
1. Input on pin TS is driven to an intermediate level between power supply and ground.
2. Input on pin TS is driven to ground.
9RSHULQW
5
N
76
5
N
SXVKEXWWRQ
FRQQHFWHGWR
FRYHU
SXVKEXWWRQ
FRQQHFWHGWR
FRYHU
966
3&[
Q)
DDD
(1) When using switches or push-buttons, it is recommended to connect a 1 nF capacitance to the TS
pin to ensure proper switching.
Fig 20. Timestamp detection with two push-buttons on the TS pin (for example, for
tamper detection)
The timestamp function is enabled by default after power-on and it can be switched off by
setting the control bit TSOFF (register Timestp_ctl).
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
39 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
A most common application of the timestamp function is described in Ref. 3 “AN11186”.
See Section 8.12.5 for a description of interrupt generation from the timestamp function.
8.11.1 Timestamp flag
1. When the TS input pin is driven to an intermediate level between the power supply
and ground, either on the falling edge from VDD or on the rising edge from ground,
then the following sequence occurs:
a. The actual date and time are stored in the timestamp registers.
b. The timestamp flag TSF1 (register Control_1) is set.
c. If the TSIE bit (register Control_2) is active, an interrupt on the INT pin is
generated.
The TSF1 flag can be cleared by command. Clearing the flag clears the interrupt.
Once TSF1 is cleared, it will only be set again when a new negative or positive edge
on pin TS is detected.
2. When the TS input pin is driven to ground, the following sequence occurs:
a. The actual date and time are stored in the timestamp registers.
b. In addition to the TSF1 flag, the TSF2 flag (register Control_2) is set.
c. If the TSIE bit is active, an interrupt on the INT pin is generated.
The TSF1 and TSF2 flags can be cleared by command; clearing both flags clears the
interrupt. Once TSF2 is cleared, it will only be set again when TS pin is driven to
ground once again.
8.11.2 Timestamp mode
The timestamp function has two different modes selected by the control bit TSM
(timestamp mode) in register Timestp_ctl:
• If TSM is logic 0 (default): in subsequent trigger events without clearing the timestamp
flags, the last timestamp event is stored
• If TSM is logic 1: in subsequent trigger events without clearing the timestamp flags,
the first timestamp event is stored
The timestamp function also depends on the control bit BTSE in register Control_3, see
Section 8.11.4.
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
40 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
8.11.3 Timestamp registers
8.11.3.1
Register Timestp_ctl
Table 57. Timestp_ctl - timestamp control register (address 12h) bit allocation
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as X are undefined at power-on and
unchanged by subsequent resets.
Bit
Symbol
7
6
5
TSM
TSOFF
-
0
0
-
Reset
value
4
3
2
1
0
X
X
1_O_16_TIMESTP[4:0]
X
X
X
Table 58. Timestp_ctl - timestamp control register (address 12h) bit description
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as X are undefined at power-on and
unchanged by subsequent resets.
Bit
Symbol
Value
Description
7
TSM
0
in subsequent events without clearing the timestamp
flags, the last event is stored
1
in subsequent events without clearing the timestamp
flags, the first event is stored
0
timestamp function active
1
timestamp function disabled
-
unused
6
TSOFF
5
-
4 to 0
1_O_16_TIMESTP[4:0]
8.11.3.2
1⁄
16
second timestamp information coded in BCD
format
Register Sec_timestp
Table 59. Sec_timestp - second timestamp register (address 13h) bit allocation
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as X are undefined at power-on and
unchanged by subsequent resets.
Bit
7
Symbol
-
Reset
value
-
6
5
X
X
4
3
2
1
0
X
X
SECOND_TIMESTP (0 to 59)
X
X
X
Table 60. Sec_timestp - second timestamp register (address 13h) bit description
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as X are undefined at power-on and
unchanged by subsequent resets.
Bit
Symbol
Value
Place value Description
7
-
-
-
unused
6 to 4
SECOND_TIMESTP
0 to 5
ten’s place
second timestamp information coded in BCD format
0 to 9
unit place
3 to 0
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
41 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
8.11.3.3
Register Min_timestp
Table 61. Min_timestp - minute timestamp register (address 14h) bit allocation
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as X are undefined at power-on and
unchanged by subsequent resets.
Bit
7
Symbol
-
Reset
value
-
6
5
4
3
2
1
0
X
X
MINUTE_TIMESTP (0 to 59)
X
X
X
X
X
Table 62. Min_timestp - minute timestamp register (address 14h) bit description
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as X are undefined at power-on and
unchanged by subsequent resets.
Bit
Symbol
Value
Place value Description
7
-
-
-
unused
6 to 4
MINUTE_TIMESTP
0 to 5
ten’s place
minute timestamp information coded in BCD format
0 to 9
unit place
3 to 0
8.11.3.4
Register Hour_timestp
Table 63. Hour_timestp - hour timestamp register (address 15h) bit allocation
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as X are undefined at power-on and
unchanged by subsequent resets.
Bit
7
6
5
Symbol
-
-
AMPM
4
3
2
1
0
HOUR_TIMESTP (1 to 12) in 12-hour mode
HOUR_TIMESTP (0 to 23) in 24-hour mode
Reset
value
-
-
X
X
X
X
X
X
Table 64. Hour_timestp - hour timestamp register (address 15h) bit description
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as X are undefined at power-on and
unchanged by subsequent resets.
Bit
Symbol
Value
Place value Description
7 to 6
-
-
-
unused
0
-
indicates AM
1
-
indicates PM
0 to 1
ten’s place
0 to 9
unit place
hour timestamp information coded in BCD format
when in 12-hour mode
0 to 2
ten’s place
0 to 9
unit place
12-hour
mode[1]
5
AMPM
4
HOUR_TIMESTP
3 to 0
24-hour
5 to 4
mode[1]
HOUR_TIMESTP
3 to 0
[1]
hour timestamp information coded in BCD format
when in 24-hour mode
Hour mode is set by the bit 12_24 in register Control_1.
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
42 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
8.11.3.5
Register Day_timestp
Table 65. Day_timestp - day timestamp register (address 16h) bit allocation
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as X are undefined at power-on and
unchanged by subsequent resets.
Bit
7
6
Symbol
-
-
Reset
value
-
-
5
4
3
2
1
0
X
X
DAY_TIMESTP (1 to 31)
X
X
X
X
Table 66. Day_timestp - day timestamp register (address 16h) bit description
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as X are undefined at power-on and
unchanged by subsequent resets.
Bit
Symbol
Value
Place value Description
7 to 6
-
-
-
unused
5 to 4
DAY_TIMESTP
0 to 3
ten’s place
day timestamp information coded in BCD format
0 to 9
unit place
3 to 0
8.11.3.6
Register Mon_timestp
Table 67. Mon_timestp - month timestamp register (address 17h) bit allocation
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as X are undefined at power-on and
unchanged by subsequent resets.
Bit
7
6
5
Symbol
-
-
-
Reset
value
-
-
-
4
3
2
1
0
MONTH_TIMESTP (1 to 12)
X
X
X
X
X
Table 68. Mon_timestp - month timestamp register (address 17h) bit description
Bit positions labeled as - are not implemented and return 0 when read. Bits labeled as X are undefined at power-on and
unchanged by subsequent resets.
Bit
Symbol
Value
Place value Description
7 to 5
-
-
-
unused
4
MONTH_TIMESTP
0 to 1
ten’s place
month timestamp information coded in BCD format
0 to 9
unit place
3 to 0
8.11.3.7
Register Year_timestp
Table 69. Year_timestp - year timestamp register (address 18h) bit allocation
Bits labeled as X are undefined at power-on and unchanged by subsequent resets.
Bit
7
6
5
Symbol
4
3
2
1
0
X
X
X
YEAR_TIMESTP (0 to 99)
Reset
value
X
X
X
X
X
Table 70. Year_timestp - year timestamp register (address 18h) bit description
Bits labeled as X are undefined at power-on and unchanged by subsequent resets.
Bit
Symbol
Value
Place value Description
7 to 4
YEAR_TIMESTP
0 to 9
ten’s place
0 to 9
unit place
3 to 0
PCF2129
Product data sheet
year timestamp information coded in BCD format
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
43 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
8.11.4 Dependency between Battery switch-over and timestamp
The timestamp function depends on the control bit BTSE in register Control_3:
Table 71.
Battery switch-over and timestamp
BTSE
BF
Description
0
-
[1]
0
[1]
1
the battery switch-over does not affect the
timestamp registers
If a battery switch-over event occurs:
the timestamp registers store the time and
date when the switch-over occurs;
after this event occurred BF is set logic 1
1
the timestamp registers are not modified;
in this condition subsequent battery
switch-over events or falling edges on pin TS
are not registered
[1]
Default value.
8.12 Interrupt output, INT
PCF2129 has an interrupt output pin INT which is open-drain, active LOW (requiring a
pull-up resistor if used). Interrupts may be sourced from different places:
•
•
•
•
•
•
second or minute timer
watchdog timer
alarm
timestamp
battery switch-over
battery low detection
The control bit TI_TP (register Watchdg_tim_ctl) is used to configure whether the
interrupts generated from the second/minute timer (flag MSF in register Control_2) are
pulsed signals or a permanently active signal. All the other interrupt sources generate a
permanently active interrupt signal which follows the status of the corresponding flags.
When the interrupt sources are all disabled, INT remains high-impedance.
• The flags MSF, AF, TSFx, and BF can be cleared by command.
• The flag WDTF is read only. How it can be cleared is explained in Section 8.10.5.
• The flag BLF is read only. It is cleared automatically from the battery low detection
circuit when the battery is replaced.
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
44 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
6,
6(&21'6&2817(5
0,
0,187(6&2817(5
06)
0,187(
6(&21')/$*
6(7
&/($5
WRLQWHUIDFH
UHDG06)
38/6(
*(1(5$725
75,**(5
&/($5
6,0,
7,B73
,17SLQ
IURPLQWHUIDFH
FOHDU06)
:'B&' :$7&+'2*
&2817(5
0&8ORDGLQJ
ZDWFKGRJFRXQWHU
VHWDODUP
IODJ$)
:'7)
:$7&+'2*
7,0(5)/$*
6(7
&/($5
WRLQWHUIDFH
UHDG$)
$,(
76)[7,0(67$03
)/$*
6(7
&/($5
WRLQWHUIDFH
UHDG76)[
76,(
%)%$77(5<
)/$*
6(7
&/($5
WRLQWHUIDFH
UHDG%)
%,(
%/)%$77(5<
/2:)/$*
6(7
&/($5
WRLQWHUIDFH
UHDG%/)
%/,(
IURPLQWHUIDFH
FOHDU76)
VHWEDWWHU\
IODJ%)
IURPLQWHUIDFH
FOHDU%)
VHWEDWWHU\
ORZIODJ%/)
:'B&' $)$/$50
)/$*
6(7
&/($5
IURPLQWHUIDFH
FOHDU$)
VHWWLPHVWDPS
IODJ76)[
WRLQWHUIDFH
UHDG:'B&'
IURPEDWWHU\
ORZGHWHFWLRQ
FLUFXLWFOHDU%)
DDM
When SI, MI, WD_CD, AIE, TSIE, BIE, BLIE are all disabled, INT remains high-impedance.
Fig 21. Interrupt block diagram
8.12.1 Minute and second interrupts
Minute and second interrupts are generated by predefined timers. The timers can be
enabled independently from one another by the bits MI and SI in register Control_1.
However, a minute interrupt enabled on top of a second interrupt cannot be
distinguishable since it occurs at the same time.
The minute/second flag MSF (register Control_2) is set logic 1 when either the seconds or
the minutes counter increments according to the enabled interrupt (see Table 72). The
MSF flag can be cleared by command.
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
45 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
Table 72.
Effect of bits MI and SI on pin INT and bit MSF
MI
SI
Result on INT
Result on MSF
0
0
no interrupt generated
MSF never set
1
0
an interrupt once per minute
MSF set when minutes
counter increments
0
1
an interrupt once per second
MSF set when seconds
counter increments
1
1
an interrupt once per second
MSF set when seconds
counter increments
When MSF is set logic 1:
• If TI_TP is logic 1, the interrupt is generated as a pulsed signal.
• If TI_TP is logic 0, the interrupt is permanently active signal that remains until MSF is
cleared.
VHFRQGVFRXQWHU
PLQXWHVFRXQWHU
,17ZKHQ6,HQDEOHG
06)ZKHQ6,HQDEOHG
,17ZKHQRQO\0,HQDEOHG
06)ZKHQRQO\0,HQDEOHG
DDI
In this example, bit TI_TP is logic 1 and the MSF flag is not cleared after an interrupt.
Fig 22. INT example for SI and MI when TI_TP is logic 1
VHFRQGVFRXQWHU
PLQXWHVFRXQWHU
,17ZKHQ6,HQDEOH
06)ZKHQ6,HQDEOH
,17ZKHQRQO\0,HQDEOHG
06)ZKHQRQO\0,HQDEOHG
DDJ
In this example, bit TI_TP is logic 0 and the MSF flag is cleared after an interrupt.
Fig 23. INT example for SI and MI when TI_TP is logic 0
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
46 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
The pulse generator for the minute/second interrupt operates from an internal 64 Hz clock
and generates a pulse of 1⁄64 seconds in duration.
8.12.2 INT pulse shortening
If the MSF flag (register Control_2) is cleared before the end of the INT pulse, then the
INT pulse is shortened. This allows the source of a system interrupt to be cleared
immediately when it is serviced, that is, the system does not have to wait for the
completion of the pulse before continuing; see Figure 24. Instructions for clearing the bit
MSF can be found in Section 8.10.5.
VHFRQGVFRXQWHU
06)
,17
6&/
WKFORFN
LQVWUXFWLRQ
&/($5,16758&7,21
DDI
(1) Indicates normal duration of INT pulse.
The timing shown for clearing bit MSF is also valid for the non-pulsed interrupt mode, that is, when
TI_TP is logic 0, where the INT pulse may be shortened by setting both bits MI and SI logic 0.
Fig 24. Example of shortening the INT pulse by clearing the MSF flag
8.12.3 Watchdog timer interrupts
The generation of interrupts from the watchdog timer is controlled using the WD_CD bit
(register Watchdg_tim_ctl). The interrupt is generated as an active signal which follows
the status of the watchdog timer flag WDTF (register Control_2). No pulse generation is
possible for watchdog timer interrupts.
The interrupt is cleared when the flag WDTF is reset. WDTF is a read-only bit and cannot
be cleared by command. Instructions for clearing it can be found in Section 8.10.5.
8.12.4 Alarm interrupts
Generation of interrupts from the alarm function is controlled by the bit AIE (register
Control_2). If AIE is enabled, the INT pin follows the status of bit AF (register Control_2).
Clearing AF immediately clears INT. No pulse generation is possible for alarm interrupts.
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
47 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
PLQXWHFRXQWHU
PLQXWHDODUP
$)
,17
6&/
WKFORFN
LQVWUXFWLRQ
&/($5,16758&7,21
DDI
Example where only the minute alarm is used and no other interrupts are enabled.
Fig 25. AF timing diagram
8.12.5 Timestamp interrupts
Interrupt generation from the timestamp function is controlled using the TSIE bit (register
Control_2). If TSIE is enabled, the INT pin follows the status of the flags TSFx. Clearing
the flags TSFx immediately clears INT. No pulse generation is possible for timestamp
interrupts.
8.12.6 Battery switch-over interrupts
Generation of interrupts from the battery switch-over is controlled by the BIE bit (register
Control_3). If BIE is enabled, the INT pin follows the status of bit BF in register Control_3
(see Table 71). Clearing BF immediately clears INT. No pulse generation is possible for
battery switch-over interrupts.
8.12.7 Battery low detection interrupts
Generation of interrupts from the battery low detection is controlled by the BLIE bit
(register Control_3). If BLIE is enabled, the INT pin follows the status of bit BLF (register
Control_3). The interrupt is cleared when the battery is replaced (BLF is logic 0) or when
bit BLIE is disabled (BLIE is logic 0). BLF is read only and therefore cannot be cleared by
command.
8.13 External clock test mode
A test mode is available which allows on-board testing. In this mode, it is possible to set
up test conditions and control the operation of the RTC.
The test mode is entered by setting bit EXT_TEST logic 1 (register Control_1). Then
pin CLKOUT becomes an input. The test mode replaces the internal clock signal (64 Hz)
with the signal applied to pin CLKOUT. Every 64 positive edges applied to pin CLKOUT
generate an increment of one second.
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
48 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
The signal applied to pin CLKOUT should have a minimum pulse width of 300 ns and a
maximum period of 1000 ns. The internal clock, now sourced from CLKOUT, is divided
down by a 26 divider chain called prescaler (see Table 73). The prescaler can be set into a
known state by using bit STOP. When bit STOP is logic 1, the prescaler is reset to 0.
STOP must be cleared before the prescaler can operate again.
From a stop condition, the first 1 second increment will take place after 32 positive edges
on pin CLKOUT. Thereafter, every 64 positive edges cause a 1 second increment.
Remark: Entry into test mode is not synchronized to the internal 64 Hz clock. When
entering the test mode, no assumption as to the state of the prescaler can be made.
Operating example:
1. Set EXT_TEST test mode (register Control_1, EXT_TEST is logic 1).
2. Set bit STOP (register Control_1, STOP is logic 1).
3. Set time registers to desired value.
4. Clear STOP (register Control_1, STOP is logic 0).
5. Apply 32 clock pulses to CLKOUT.
6. Read time registers to see the first change.
7. Apply 64 clock pulses to CLKOUT.
8. Read time registers to see the second change.
Repeat 7 and 8 for additional increments.
8.14 STOP bit function
The function of the STOP bit is to allow for accurate starting of the time circuits. STOP
causes the upper part of the prescaler (F9 to F14) to be held in reset and thus no 1 Hz ticks
are generated. The time circuits can then be set and will not increment until the STOP bit
is released. STOP doesn’t affect the CLKOUT signal but the output of the prescaler in the
range of 32 Hz to 1 Hz (see Figure 26).
/2:(535(6&$/(5
+]
26&
+]
)
+]
)
833(535(6&$/(5
+]
+]
)
+]
)
)
)
)
)
5(6
5(6
5(6
5(6
+]WLFN
VWRS
DDM
Fig 26. STOP bit functional diagram
The lower stages of the prescaler, F0 to F8, are not reset and because the I2C-bus and the
SPI-bus are asynchronous to the crystal oscillator, the accuracy of restarting the time
circuits is between 0 and one 64 Hz cycle (0.484375 s and 0.500000 s), see Table 73 and
Figure 27.
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
49 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
Table 73.
First increment of time circuits after stop release
Bit
STOP
Prescaler bits[1]
F0 to F8 - F9 to F14
1 Hz tick
Time
hh:mm:ss
Comment
12:45:12
prescaler counting normally
Clock is running normally
0
010000111-010100
STOP bit is activated by user. F0 to F8 are not reset and values cannot be predicted externally
1
xxxxxxxxx-000000
12:45:12
prescaler is reset; time circuits are frozen
08:00:00
prescaler is reset; time circuits are frozen
08:00:00
prescaler is now running
New time is set by user
1
xxxxxxxxx-000000
STOP bit is released by user
xxxxxxxxx-000000
0
xxxxxxxxx-100000
0
xxxxxxxxx-100000
0
xxxxxxxxx-110000
:
:
0
111111111-111110
0
000000000-000001
08:00:01
0
100000000-000001
08:00:01
:
:
:
0
111111111-111111
08:00:01
0
000000000-000000
0
100000000-000000
:
:
:
0
111111111-111110
08:00:01
0
000000000-000001
08:00:02
V
0
08:00:00
08:00:00
08:00:00
:
V
08:00:00
0 to 1 transition of F14 increments the time circuits
08:00:01
0 to 1 transition of F14 increments the time circuits
DDM
[1]
F0 is clocked at 32.768 kHz.
+]
VWRSUHOHDVHG
PVPV
DDM
Fig 27. STOP bit release timing
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
50 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
9. Interfaces
The PCF2129 has an I2C-bus or SPI-bus interface using the same pins. The selection is
done using the interface selection pin IFS (see Table 74).
Table 74.
Interface selection input pin IFS
Pin
Connection
Bus interface
Reference
IFS
VSS
SPI-bus
Section 9.1
BBS
I2C-bus
Section 9.2
9''
9''
6&/
538
538
6',
6&/
6'2
6'$
&(
9''
6&/
9''
6&/
6',
6',
6'2
%%6
6'2
6'$&(
,)6
%%6
6'$&(
,)6
3&)
3&)
966
966
966
966
DDD
DDD
To select the I2C-bus interface, pin IFS has to be
connected to pin BBS.
To select the SPI-bus interface, pin IFS has to be
connected to pin VSS.
b. I2C-bus interface selection
a. SPI-bus interface selection
Fig 28. Interface selection
9.1 SPI-bus interface
Data transfer to and from the device is made by a 3 line SPI-bus (see Table 75). The data
lines for input and output are split. The data input and output line can be connected
together to facilitate a bidirectional data bus (see Figure 29). The SPI-bus is initialized
whenever the chip enable line pin SDA/CE is inactive.
6',
6',
6'2
6'2
WZRZLUHPRGH
VLQJOHZLUHPRGH
DDL
Fig 29. SDI, SDO configurations
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
51 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
Table 75.
Serial interface
Symbol
Function
SDA/CE
Description
[1]
chip enable input;
active LOW
when HIGH, the interface is reset;
input may be higher than VDD
SCL
serial clock input
when SDA/CE is HIGH, input may float;
SDI
serial data input
when SDA/CE is HIGH, input may float;
input may be higher than VDD
input may be higher than VDD;
input data is sampled on the rising edge of
SCL
SDO
serial data output
push-pull output;
drives from VSS to Voper(int) (VBBS);
output data is changed on the falling edge of
SCL
[1]
The chip enable must not be wired permanently LOW.
9.1.1 Data transmission
The chip enable signal is used to identify the transmitted data. Each data transfer is a
whole byte, with the Most Significant Bit (MSB) sent first.
The transmission is controlled by the active LOW chip enable signal SDA/CE. The first
byte transmitted is the command byte. Subsequent bytes are either data to be written or
data to be read (see Figure 30).
GDWDEXV
&200$1'
'$7$
'$7$
'$7$
6'$&(
DDD
Fig 30. Data transfer overview
The command byte defines the address of the first register to be accessed and the
read/write mode. The address counter will auto increment after every access and will
reset to zero after the last valid register is accessed. The R/W bit defines if the following
bytes are read or write information.
Table 76.
Command byte definition
Bit
Symbol
7
R/W
6 to 5
SA
Value
Description
data read or write selection
0
write data
1
read data
01
subaddress;
other codes will cause the device to ignore
data transfer
4 to 0
PCF2129
Product data sheet
RA
00h to 1Bh
register address
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
52 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
5:
6$
DGGUK
VHFRQGVGDWD%&'
PLQXWHVGDWD%&'
E E E E E E E E E E E E E E E E E E E E E E E E
6&/
6',
6'$&(
DGGUHVV
[[
FRXQWHU
DDM
In this example, the Seconds register is set to 45 seconds and the Minutes register to 10 minutes.
Fig 31. SPI-bus write example
5:
6$
DGGUK
PRQWKVGDWD%&'
\HDUVGDWD%&'
E E E E E E E E E E E E E E E E E E E E E E E E
6&/
6',
6'2
6'$&(
DGGUHVV
[[
FRXQWHU
$
DDM
In this example, the registers Months and Years are read. The pins SDI and SDO are not connected together. For this
configuration, it is important that pin SDI is never left floating. It must always be driven either HIGH or LOW. If pin SDI is left
open, high IDD currents may result.
Fig 32. SPI-bus read example
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
53 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
9.2 I2C-bus interface
The I2C-bus is for bidirectional, two-line communication between different ICs or modules.
The two lines are a Serial DAta line (SDA) and a Serial CLock line (SCL). Both lines are
connected to a positive supply by a pull-up resistor. Data transfer is initiated only when the
bus is not busy.
9.2.1 Bit transfer
One data bit is transferred during each clock pulse. The data on the SDA line remains
stable during the HIGH period of the clock pulse as changes in the data line at this time
are interpreted as control signals (see Figure 33).
6'$
6&/
GDWDOLQH
VWDEOH
GDWDYDOLG
FKDQJH
RIGDWD
DOORZHG
PEF
Fig 33. Bit transfer
9.2.2 START and STOP conditions
Both data and clock lines remain HIGH when the bus is not busy. A HIGH-to-LOW
transition of the data line, while the clock is HIGH, is defined as the START condition S.
A LOW-to-HIGH transition of the data line while the clock is HIGH is defined as the STOP
condition P (see Figure 34).
6'$
6'$
6&/
6&/
6
3
67$57FRQGLWLRQ
6723FRQGLWLRQ
PEF
Fig 34. Definition of START and STOP conditions
Remark: For the PCF2129, a repeated START is not allowed. Therefore a STOP has to
be released before the next START.
9.2.3 System configuration
A device generating a message is a transmitter; a device receiving a message is the
receiver. The device that controls the message is the master; and the devices which are
controlled by the master are the slaves.
The PCF2129 can act as a slave transmitter and a slave receiver.
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
54 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
6'$
6&/
0$67(5
75$160,77(5
5(&(,9(5
6/$9(
75$160,77(5
5(&(,9(5
6/$9(
5(&(,9(5
0$67(5
75$160,77(5
5(&(,9(5
0$67(5
75$160,77(5
PED
Fig 35. System configuration
9.2.4 Acknowledge
The number of data bytes transferred between the START and STOP conditions from
transmitter to receiver is unlimited. Each byte of 8 bits is followed by an acknowledge
cycle.
• A slave receiver which is addressed must generate an acknowledge after the
reception of each byte.
• Also a master receiver must generate an acknowledge after the reception of each
byte that has been clocked out of the slave transmitter.
• The device that acknowledges must pull-down the SDA line during the acknowledge
clock pulse, so that the SDA line is stable LOW during the HIGH period of the
acknowledge related clock pulse (set-up and hold times must be considered).
• A master receiver must signal an end of data to the transmitter by not generating an
acknowledge on the last byte that has been clocked out of the slave. In this event, the
transmitter must leave the data line HIGH to enable the master to generate a STOP
condition.
Acknowledgement on the I2C-bus is illustrated in Figure 36.
GDWDRXWSXW
E\WUDQVPLWWHU
QRWDFNQRZOHGJH
GDWDRXWSXW
E\UHFHLYHU
DFNQRZOHGJH
6&/IURP
PDVWHU
6
67$57
FRQGLWLRQ
FORFNSXOVHIRU
DFNQRZOHGJHPHQW
PEF
Fig 36. Acknowledgement on the I2C-bus
9.2.5 I2C-bus protocol
After a start condition, a valid hardware address has to be sent to a PCF2129 device. The
appropriate I2C-bus slave address is 1010001. The entire I2C-bus slave address byte is
shown in Table 77.
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
55 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
I2C slave address byte
Table 77.
Slave address
Bit
7
6
5
4
3
2
1
0
0
1
0
0
0
1
R/W
MSB
LSB
1
The R/W bit defines the direction of the following single or multiple byte data transfer (read
is logic 1, write is logic 0).
For the format and the timing of the START condition (S), the STOP condition (P), and the
acknowledge (A) refer to the I2C-bus specification Ref. 13 “UM10204” and the
characteristics table (Table 82). In the write mode, a data transfer is terminated by sending
a STOP condition. A repeated START (Sr) condition is not applicable.
DFNQRZOHGJH
IURP3&)
6
VODYHDGGUHVV
DFNQRZOHGJH
IURP3&)
DFNQRZOHGJH
IURP3&)
$
$
$
ZULWHELW
WRQGDWDE\WHV
SOXV$&.
UHJLVWHUDGGUHVV
KWR%K
3
6
6723
67$57
DDD
Fig 37. Bus protocol, writing to registers
DFNQRZOHGJH
IURP3&)
6
VODYHDGGUHVV
DFNQRZOHGJH
IURP3&)
$
$
UHJLVWHUDGGUHVV
KWR%K
ZULWHELW
DFNQRZOHGJH
IURP3&)
6
VODYHDGGUHVV
$
VHWUHJLVWHU
DGGUHVV
3
6723
DFNQRZOHGJH
IURPPDVWHU
'$7$%<7(
$
QRDFNQRZOHGJH
/$67'$7$%<7(
$
WRQGDWDE\WHV
SOXV$&.
UHDGELW
3
UHDGUHJLVWHU
GDWD
DDD
Fig 38. Bus protocol, reading from registers
9.3 Bus communication and battery backup operation
To save power during battery backup operation (see Section 8.5.1), the bus interfaces are
inactive. Therefore the communication via I2C- or SPI-bus should be terminated before
the supply of the PCF2129 is switched from VDD to VBAT.
Remark: If the I2C-bus communication was terminated uncontrolled, the I2C-bus has to
be reinitialized by sending a STOP followed by a START after the device switched back
from battery backup operation to VDD supply operation.
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
56 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
10. Internal circuitry
9''
6&/
9%$7
%%6
6',
6'2
,17
6'$&(
,)6
76
&/.287
966
3&)
DDD
Fig 39. Device diode protection diagram of PCF2129
11. Safety notes
CAUTION
This device is sensitive to ElectroStatic Discharge (ESD). Observe precautions for handling
electrostatic sensitive devices.
Such precautions are described in the ANSI/ESD S20.20, IEC/ST 61340-5, JESD625-A or
equivalent standards.
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
57 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
12. Limiting values
Table 78. Limiting values
In accordance with the Absolute Maximum Rating System (IEC 60134).
Symbol
Parameter
VDD
Conditions
Min
Max
Unit
supply voltage
0.5
+6.5
V
IDD
supply current
50
+50
mA
Vi
input voltage
0.5
+6.5
V
II
input current
10
+10
mA
VO
output voltage
0.5
+6.5
V
IO
output current
at pin SDA/CE
VBAT
battery supply voltage
Ptot
total power dissipation
10
+10
mA
10
+20
mA
0.5
+6.5
V
-
300
mW
HBM
[1]
-
4000
V
CDM
[2]
-
1250
V
latch-up current
[3]
-
200
mA
Tstg
storage temperature
[4]
55
+85
C
Tamb
ambient temperature
40
+85
C
VESD
Ilu
electrostatic discharge
voltage
operating device
[1]
Pass level; Human Body Model (HBM) according to Ref. 7 “JESD22-A114”.
[2]
Pass level; Charged-Device Model (CDM), according to Ref. 8 “JESD22-C101”.
[3]
Pass level; latch-up testing according to Ref. 9 “JESD78” at maximum ambient temperature (Tamb(max)).
[4]
According to the store and transport requirements (see Ref. 14 “UM10569”) the devices have to be stored at a temperature of +8 C to
+45 C and a humidity of 25 % to 75 %.
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
58 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
13. Static characteristics
Table 79. Static characteristics
VDD = 1.8 V to 4.2 V; VSS = 0 V; Tamb = 40 C to +85 C, unless otherwise specified.
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
Supplies
[1]
VDD
supply voltage
1.8
-
4.2
V
VBAT
battery supply voltage
1.8
-
4.2
V
VDD(cal)
calibration supply voltage
-
3.3
-
V
Vlow
low voltage
-
1.2
-
V
IDD
supply current
SPI-bus (fSCL = 6.5 MHz)
-
-
800
A
I2C-bus
-
-
200
A
interface active;
supplied by VDD
(fSCL = 400 kHz)
Hz)[2];
interface inactive (fSCL = 0
TCR[1:0] = 00 (see Table 13 on page 12)
PWRMNG[2:0] = 111 (see Table 19 on page 16);
TSOFF = 1 (see Table 58 on page 41);
COF[2:0] = 111 (see Table 15 on page 14)
VDD = 1.8 V
-
470
-
nA
VDD = 3.3 V
-
700
1500
nA
VDD = 4.2 V
-
800
-
nA
-
nA
PWRMNG[2:0] = 111 (see Table 19 on page 16);
TSOFF = 1 (see Table 58 on page 41);
COF[2:0] = 000 (see Table 15 on page 14)
VDD = 1.8 V
-
560
VDD = 3.3 V
-
850
-
nA
VDD = 4.2 V
-
1050
-
nA
PWRMNG[2:0] = 000 (see Table 19 on page 16);
TSOFF = 0 (see Table 58 on page 41);
COF[2:0] = 111 (see Table 15 on page 14)
VDD or VBAT = 1.8 V
[3]
-
1750
-
nA
VDD or VBAT = 3.3 V
[3]
-
2150
-
nA
VDD or VBAT = 4.2 V
[3]
-
2350
3500
nA
PWRMNG[2:0] = 000 (see Table 19 on page 16);
TSOFF = 0 (see Table 58 on page 41);
COF[2:0] = 000 (see Table 15 on page 14)
IL(bat)
battery leakage current
PCF2129
Product data sheet
VDD or VBAT = 1.8 V
[3]
-
1840
-
nA
VDD or VBAT = 3.3 V
[3]
-
2300
-
nA
VDD or VBAT = 4.2 V
[3]
-
2600
-
nA
-
50
100
nA
VDD is active supply;
VBAT = 3.0 V
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
59 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
Table 79. Static characteristics …continued
VDD = 1.8 V to 4.2 V; VSS = 0 V; Tamb = 40 C to +85 C, unless otherwise specified.
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
Power management
Vth(sw)bat
battery switch threshold
voltage
-
2.5
-
V
Vth(bat)low
low battery threshold
voltage
-
2.5
-
V
2.25
-
2.85
V
Tamb = 25 C
Inputs[4]
VI
input voltage
0.5
-
VDD + 0.5
V
VIL
LOW-level input voltage
-
-
0.25VDD
V
-
-
0.3VDD
V
Tamb = 20 C to +85 C;
VDD > 2.0 V
VIH
HIGH-level input voltage
ILI
input leakage current
0.7VDD
-
-
V
-
0
-
A
1
-
+1
A
-
-
7
pF
on pins CLKOUT, INT,
referring to external pull-up
0.5
-
+5.5
V
on pin BBS
1.8
-
4.2
V
VI = VDD or VSS
post ESD event
[5]
input capacitance
Ci
Outputs
output voltage
VO
on pin SDO
0.5
-
VDD + 0.5
V
VOH
HIGH output voltage
on pin SDO
0.8VDD
-
VDD
V
VOL
LOW output voltage
on pins CLKOUT, INT, and
SDO
VSS
-
0.2VDD
V
IOL
LOW-level output current
output sink current;
VOL = 0.4 V
3
17
-
mA
on all other outputs
1.0
-
-
mA
on pin SDA/CE
[6]
IOH
HIGH-level output current
output source current;
on pin SDO;
VOH = 3.8 V;
VDD = 4.2 V
1.0
-
-
mA
ILO
output leakage current
VO = VDD or VSS
-
0
-
A
1
-
+1
A
post ESD event
[1]
For reliable oscillator start-up at power-on: VDD(po)min = VDD(min) + 0.3 V.
[2]
Timer source clock = 1⁄60 Hz, level of pins SDA/CE, SDI, and SCL is VDD or VSS.
[3]
When the device is supplied by the VBAT pin instead of the VDD pin, the current values for IBAT are as specified for IDD under the same
conditions.
[4]
The I2C-bus and SPI-bus interfaces of PCF2129 are 5 V tolerant.
[5]
Tested on sample basis.
[6]
For further information, see Figure 40.
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
60 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
13.1 Current consumption characteristics, typical
DDO
,2/
P$
9''9
Typical value; VOL = 0.4 V.
Fig 40. IOL on pin SDA/CE
DDM
,''
$
9'' 9
9'' 9
7HPSHUDWXUH&
CLKOUT disabled; PWRMNG[2:0] = 111; TSOFF = 1; TS input floating.
Fig 41. IDD as a function of temperature
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
61 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
DDM
,''
$
&/.287HQDEOHGDW
N+]
&/.2872))
9''9
a. PWRMNG[2:0] = 111; TSOFF = 1; Tamb = 25 C; TS input floating
DDM
,''
$
&/.287HQDEOHGDW
N+]
&/.2872))
9''9
b. PWRMNG[2:0] = 000; TSOFF = 0; Tamb = 25 C; TS input floating
Fig 42. IDD as a function of VDD
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
62 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
,''
$
3:50*>@
DDD
Interface inactive; Tamb = 25 C; VBAT = 0 V; default configuration.
Description of the PWRMNG[2:0] settings, see Table 19 on page 16.
(1) VDD = 1.8 V.
(2) VDD = 3.3 V.
(3) VDD = 4.2 V.
(4) VDD or VBAT = 1.8 V.
(5) VDD or VBAT = 3.3 V.
(6) VDD or VBAT = 4.2 V.
Fig 43. Typical IDD as a function of the power management settings
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
63 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
13.2 Frequency characteristics
Table 80. Frequency characteristics
VDD = 1.8 V to 4.2 V; VSS = 0 V; Tamb = +25 C, unless otherwise specified.
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
fo
output frequency
on pin CLKOUT;
VDD or VBAT = 3.3 V;
COF[2:0] = 000;
AO[3:0] = 1000
-
32.768
-
kHz
f/f
frequency stability
VDD or VBAT = 3.3 V
PCF2129AT
Tamb = 15 C to +60 C
[1][2]
-
3
5
ppm
Tamb = 25 C to 15 C
and
Tamb = +60 C to +65 C
[1][2]
-
5
10
ppm
Tamb = 30 C to +80 C
[1][2]
-
3
8
ppm
Tamb = 40 C to 30 C
and
Tamb = +80 C to +85 C
[1][2]
-
5
15
ppm
[3]
-
-
3
ppm
[3]
-
-
3
ppm
-
-
8
ppm
-
1
-
ppm/V
PCF2129T
fxtal/fxtal
relative crystal
frequency variation
crystal aging
PCF2129AT
first year;
VDD or VBAT = 3.3 V
PCF2129T
first year
ten years
f/V
[1]
frequency variation
with voltage
on pin CLKOUT
1 ppm corresponds to a time deviation of 0.0864 seconds per day.
[2]
Only valid if CLKOUT frequencies are not equal to 32.768 kHz or if CLKOUT is disabled.
[3]
Not production tested. Effects of reflow soldering are included (see Ref. 3 “AN11186”).
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
64 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
DDD
)UHTXHQF\
VWDELOLW\
SSP
SSP
SSP
SSP
7HPSHUDWXUH&
(1) Typical temperature compensated frequency response.
(2) Uncompensated typical tuning-fork crystal frequency.
Fig 44. Typical characteristic of frequency with respect to temperature of PCF2129AT
DDD
)UHTXHQF\
VWDELOLW\
SSP
SSP
SSP
SSP
7HPSHUDWXUH&
(1) Typical temperature compensated frequency response.
(2) Uncompensated typical tuning-fork crystal frequency.
Fig 45. Typical characteristic of frequency with respect to temperature of PCF2129T
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
65 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
14. Dynamic characteristics
14.1 SPI-bus timing characteristics
Table 81. SPI-bus characteristics
VDD = 1.8 V to 4.2 V; VSS = 0 V; Tamb = 40 C to +85 C, unless otherwise specified. All timing values are valid within the
operating supply voltage at ambient temperature and referenced to VIL and VIH with an input voltage swing of VSS to VDD (see
Figure 46).
Symbol
Parameter
Conditions
VDD = 1.8 V
VDD = 4.2 V
Min
Min
Max
Unit
Max
Pin SCL
fclk(SCL)
SCL clock frequency
-
2.0
-
6.5
MHz
tSCL
SCL time
800
-
140
-
ns
tclk(H)
clock HIGH time
100
-
70
-
ns
tclk(L)
clock LOW time
400
-
70
-
ns
tr
rise time
for SCL signal
-
100
-
100
ns
tf
fall time
for SCL signal
-
100
-
100
ns
Pin SDA/CE
tsu(CE_N)
CE_N set-up time
60
-
30
-
ns
th(CE_N)
CE_N hold time
40
-
25
-
ns
trec(CE_N)
CE_N recovery time
100
-
30
-
ns
tw(CE_N)
CE_N pulse width
-
0.99
-
0.99
s
Pin SDI
tsu
set-up time
set-up time for SDI data
70
-
20
-
ns
th
hold time
hold time for SDI data
70
-
20
-
ns
SDO read delay time
CL = 50 pF
-
225
-
55
ns
Pin SDO
td(R)SDO
tdis(SDO)
SDO disable time
tt(SDI-SDO)
transition time from
SDI to SDO
[1]
[1]
to avoid bus conflict
-
90
-
25
ns
0
-
0
-
ns
No load value; bus is held up by bus capacitance; use RC time constant with application values.
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
66 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
WZ&(B1
&(
WVX&(B1
WU
WUHF&(B1
WI
WFON6&/
WK&(B1
6&/
WFON/
WFON+
:5,7(
WVX
WK
6',
6'2
5:
6$
5$
E
E
E
E
E
KLJK=
5($'
6',
E
WW6',6'2
6'2
KLJK=
WG56'2
E
WGLV6'2
E
E
DDD
Fig 46. SPI-bus timing
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
67 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
14.2 I2C-bus timing characteristics
Table 82. I2C-bus characteristics
All timing characteristics are valid within the operating supply voltage and ambient temperature range and reference to 30 %
and 70 % with an input voltage swing of VSS to VDD (see Figure 47).
Symbol
Parameter
Standard mode
Fast-mode (Fm)
Unit
Min
Max
Min
Max
0
100
0
400
kHz
Pin SCL
[1]
fSCL
SCL clock frequency
tLOW
LOW period of the SCL clock
4.7
-
1.3
-
s
tHIGH
HIGH period of the SCL clock
4.0
-
0.6
-
s
Pin SDA/CE
tSU;DAT
data set-up time
250
-
100
-
ns
tHD;DAT
data hold time
0
-
0
-
ns
Pins SCL and SDA/CE
tBUF
bus free time between a STOP
and START condition
4.7
-
1.3
-
s
tSU;STO
set-up time for STOP condition
4.0
-
0.6
-
s
tHD;STA
hold time (repeated) START
condition
4.0
-
0.6
-
s
tSU;STA
set-up time for a repeated START
condition
4.7
-
0.6
-
s
tr
rise time of both SDA and SCL
signals
[2][3][4]
-
1000
20 + 0.1Cb
300
ns
tf
fall time of both SDA and SCL
signals
[2][3][4]
-
300
20 + 0.1Cb
300
ns
tVD;ACK
data valid acknowledge time
[5]
0.1
3.45
0.1
0.9
s
tVD;DAT
data valid time
[6]
300
-
75
-
ns
tSP
pulse width of spikes that must be
suppressed by the input filter
[7]
-
50
-
50
ns
[1]
The minimum SCL clock frequency is limited by the bus time-out feature which resets the serial bus interface if either the SDA or SCL is
held LOW for a minimum of 25 ms. The bus time-out feature must be disabled for DC operation.
[2]
A master device must internally provide a hold time of at least 300 ns for the SDA signal (refer to the VIL of the SCL signal) in order to
bridge the undefined region of the falling edge of SCL.
[3]
Cb is the total capacitance of one bus line in pF.
[4]
The maximum tf for the SDA and SCL bus lines is 300 ns. The maximum fall time for the SDA output stage, tf is 250 ns. This allows
series protection resistors to be connected between the SDA/CE pin, the SCL pin, and the SDA/SCL bus lines without exceeding the
maximum tf.
[5]
tVD;ACK is the time of the acknowledgement signal from SCL LOW to SDA (out) LOW.
[6]
tVD;DAT is the minimum time for valid SDA (out) data following SCL LOW.
[7]
Input filters on the SDA and SCL inputs suppress noise spikes of less than 50 ns.
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
68 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
35272&2/
67$57
&21',7,21
6
W6867$
%,7
06%
$
W/2:
%,7
/6%
5:
%,7
$
W+,*+
$&.12:/('*(
$
6723
&21',7,21
3
I6&/
6&/
W%8)
WU
WI
6'$
W+'67$
W68'$7
W+''$7
W9''$7
W68672
PEG
Fig 47. I2C-bus timing diagram; rise and fall times refer to 30 % and 70 %
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
69 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
15. Application information
Q)
)
9''
6&/
6',
,QWHUIDFH
ȍ
6'2
Q)
9%$7
6'$&(
%%6
,&
63,
9''
%%6
,)6
WRQ)
%%6
3&)
76
,17
,17
538
Nȍ
9''
&L
966
&/.287
&/.287
538
9''
DDD
Ci: In case mechanical switches are used, a capacitor of 1 nF is recommended.
RPU: For example, 10 k.
Fig 48. General application diagram
For information about application configuration, see Ref. 3 “AN11186”.
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
70 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
16. Package outline
62SODVWLFVPDOORXWOLQHSDFNDJHOHDGVERG\ZLGWKPP
627
'
$
(
;
F
\
+(
Y 0 $
=
4
$
$
$
$
SLQLQGH[
ș
/S
/
H
ES
GHWDLO;
Z 0
PP
VFDOH
',0(16,216LQFKGLPHQVLRQVDUHGHULYHGIURPWKHRULJLQDOPPGLPHQVLRQV
81,7
$
PD[
$
$
$
ES
F
'
(
H
+(
/
/S
4
Y
Z
\
PP
LQFKHV
=
ș
R
R
1RWH
3ODVWLFRUPHWDOSURWUXVLRQVRIPPLQFKPD[LPXPSHUVLGHDUHQRWLQFOXGHG
5()(5(1&(6
287/,1(
9(56,21
,(&
-('(&
627
(
06
-(,7$
(8523($1
352-(&7,21
,668('$7(
Fig 49. Package outline SOT163-1 (SO20) of PCF2129AT
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
71 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
62SODVWLFVPDOORXWOLQHSDFNDJHOHDGVERG\ZLGWKPP
'
627
$
(
;
F
+(
\
Y 0 $
=
4
$
$
$
$
SLQLQGH[
ș
/S
/
H
GHWDLO;
Z 0
ES
PP
VFDOH
',0(16,216LQFKGLPHQVLRQVDUHGHULYHGIURPWKHRULJLQDOPPGLPHQVLRQV
81,7
$
PD[
$
$
$
ES
F
'
(
H
+(
/
/S
4
Y
Z
\
PP
LQFKHV
=
ș
R
R
1RWH
3ODVWLFRUPHWDOSURWUXVLRQVRIPPLQFKPD[LPXPSHUVLGHDUHQRWLQFOXGHG
5()(5(1&(6
287/,1(
9(56,21
,(&
-('(&
627
(
06
-(,7$
(8523($1
352-(&7,21
,668('$7(
Fig 50. Package outline SOT162-1 (SO16) of PCF2129T
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
72 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
17. Packing information
17.1 Tape and reel information
For tape and reel packing information, see
• Ref. 11 “SOT162-1_518” on page 78 for the PCF2129T.
• Ref. 12 “SOT163-1_518” on page 78 for the PCF2129AT.
18. Soldering
For information about soldering, see Ref. 3 “AN11186”.
18.1 Footprint information
î
î
VROGHUODQGV
RFFXSLHGDUHD
SODFHPHQWDFFXUDF\
'LPHQVLRQVLQPP
VRWBIU
Fig 51. Footprint information for reflow soldering of SOT163-1 (SO20) of PCF2129AT
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
73 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
)RRWSULQWLQIRUPDWLRQIRUUHIORZVROGHULQJRI62SDFNDJH
627
+[
*[
3
+\
*\
%\
$\
&
'[
'
3
*HQHULFIRRWSULQWSDWWHUQ
5HIHUWRWKHSDFNDJHRXWOLQHGUDZLQJIRUDFWXDOOD\RXW
VROGHUODQG
RFFXSLHGDUHD
',0(16,216LQPP
3
3
$\
%\
&
'
'
*[
*\
+[
+\
VRWBIU
Fig 52. Footprint information for reflow soldering of SOT162-1 (SO16) of PCF2129T
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
74 of 86
xxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxx x x x xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxx xx xx xxxxx
xxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxx xxxxxx xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxx x x
xxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxx xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxx
xxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxxx xxx
NXP Semiconductors
PCF2129
Product data sheet
19. Appendix
19.1 Real-Time Clock selection
Table 83.
Selection of Real-Time Clocks
Type name
Alarm, Timer, Interrupt Interface IDD,
Battery Timestamp,
Watchdog
output
typical (nA) backup tamper input
Special features
Packages
PCF8563
X
1
I2C
250
-
-
-
-
SO8, TSSOP8,
HVSON10
PCF8564A
X
1
I2C
250
-
-
-
integrated oscillator caps
WLCSP
600
-
-
grade 1
high robustness,
Tamb40 C to 125 C
TSSOP8, HVSON10
Rev. 7 — 19 December 2014
All information provided in this document is subject to legal disclaimers.
PCA8565
X
1
I2C
PCA8565A
X
1
I2C
600
-
-
-
integrated oscillator caps,
Tamb40 C to 125 C
WLCSP
PCF85063
-
1
I2C
220
-
-
-
basic functions only, no
alarm
HXSON8
PCF85063A
X
1
I2C
220
-
-
-
tiny package
SO8, DFN2626-10
PCF85063B
X
1
SPI
220
-
-
-
tiny package
DFN2626-10
230
X
X
-
time stamp, battery
backup, stopwatch 1⁄100 s
SO8, TSSOP10,
TSSOP8,
DFN2626-10
X
2
PCF85263B
X
2
SPI
230
X
X
-
time stamp, battery
backup, stopwatch 1⁄100s
TSSOP10,
DFN2626-10
PCF85363A
X
2
I2C
230
X
X
-
time stamp, battery
backup, stopwatch 1⁄100s,
64 Byte RAM
TSSOP10,
DFN2626-10
PCF85363B
X
2
SPI
230
X
X
-
time stamp, battery
backup, stopwatch 1⁄100s,
64 Byte RAM
TSSOP10,
DFN2626-10
PCF8523
X
2
I2C
150
X
-
-
lowest power 150 nA in
operation, FM+ 1 MHz
SO8, HVSON8,
TSSOP14, WLCSP
PCF2123
X
1
SPI
100
-
-
-
lowest power 100 nA in
operation
TSSOP14, HVQFN16
PCF2127
X
1
I2C and
SPI
500
X
X
-
temperature
SO16
compensated, quartz built
in, calibrated, 512 Byte
RAM
PCF2129
75 of 86
© NXP Semiconductors N.V. 2014. All rights reserved.
PCF85263A
I2C
Accurate RTC with integrated quartz crystal for industrial applications
AEC-Q100
compliant
xxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxx x x x xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxx xx xx xxxxx
xxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxx xxxxxx xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxx x x
xxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxx xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxx
xxxxxxxxxxxxxxxxxxxxxxxxx xxxxxxxxxxxxxxxxxxxx xxx
Selection of Real-Time Clocks …continued
Alarm, Timer, Interrupt Interface IDD,
Battery Timestamp,
Watchdog
output
typical (nA) backup tamper input
AEC-Q100
compliant
Special features
PCF2127A
X
1
I2C and
SPI
500
X
PCF2129
X
1
I2C and
SPI
500
PCF2129A
X
1
I2C and
SPI
PCA2129
X
1
PCA21125
X
1
Packages
X
-
temperature
SO20
compensated, quartz built
in, calibrated, 512 Byte
RAM
X
X
-
temperature
SO16
compensated, quartz built
in, calibrated
500
X
X
-
temperature
SO20
compensated, quartz built
in, calibrated
I2C and
SPI
500
X
X
grade 3
temperature
SO16
compensated, quartz built
in, calibrated
SPI
820
-
-
grade 1
high robustness,
Tamb40 C to 125 C
TSSOP14
PCF2129
76 of 86
© NXP Semiconductors N.V. 2014. All rights reserved.
Accurate RTC with integrated quartz crystal for industrial applications
Rev. 7 — 19 December 2014
All information provided in this document is subject to legal disclaimers.
Type name
NXP Semiconductors
PCF2129
Product data sheet
Table 83.
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
20. Abbreviations
Table 84.
Acronym
PCF2129
Product data sheet
Abbreviations
Description
AM
Ante Meridiem
BCD
Binary Coded Decimal
CDM
Charged Device Model
CMOS
Complementary Metal-Oxide Semiconductor
DC
Direct Current
GPS
Global Positioning System
HBM
Human Body Model
I2C
Inter-Integrated Circuit
IC
Integrated Circuit
LSB
Least Significant Bit
MCU
Microcontroller Unit
MM
Machine Model
MSB
Most Significant Bit
PM
Post Meridiem
POR
Power-On Reset
PORO
Power-On Reset Override
PPM
Parts Per Million
RC
Resistance-Capacitance
RTC
Real-Time Clock
SCL
Serial CLock line
SDA
Serial DAta line
SPI
Serial Peripheral Interface
SRAM
Static Random Access Memory
TCXO
Temperature Compensated Xtal Oscillator
Xtal
crystal
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
77 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
21. References
[1]
AN10365 — Surface mount reflow soldering description
[2]
AN10853 — Handling precautions of ESD sensitive devices
[3]
AN11186 — Application and soldering information for the PCA2129 and PCF2129
TCXO RTC
[4]
IEC 60134 — Rating systems for electronic tubes and valves and analogous
semiconductor devices
[5]
IEC 61340-5 — Protection of electronic devices from electrostatic phenomena
[6]
IPC/JEDEC J-STD-020D — Moisture/Reflow Sensitivity Classification for
Nonhermetic Solid State Surface Mount Devices
[7]
JESD22-A114 — Electrostatic Discharge (ESD) Sensitivity Testing Human Body
Model (HBM)
[8]
JESD22-C101 — Field-Induced Charged-Device Model Test Method for
Electrostatic-Discharge-Withstand Thresholds of Microelectronic Components
[9]
JESD78 — IC Latch-Up Test
[10] JESD625-A — Requirements for Handling Electrostatic-Discharge-Sensitive
(ESDS) Devices
[11] SOT162-1_518 — SO16; Reel pack; SMD, 13”, packing information
[12] SOT163-1_518 — SO20; Reel pack; SMD, 13”, packing information
[13] UM10204 — I2C-bus specification and user manual
[14] UM10569 — Store and transport requirements
[15] UM10762 — User manual for the accurate RTC demo board OM13513 containing
PCF2127T and PCF2129AT
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
78 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
22. Revision history
Table 85.
Revision history
Document ID
Release date
Data sheet status
Change notice
Supersedes
PCF2129 v.7
20141219
Product data sheet
-
PCF2129AT v.6
PCF2129T v.4
Modifications:
•
The format of this data sheet has been redesigned to comply with the new identity
guidelines of NXP Semiconductors.
•
•
•
•
•
•
•
•
•
•
•
Legal texts have been adapted to the new company name where appropriate.
Combined PCF2129AT and PCF2129T data sheets to one data sheet
Added Figure 4, Figure 43 and Figure 48
Enhanced Figure 8, Figure 12, Figure 20, Section 8.11.1, Figure 37, Figure 38
Added Section 9.3
Changed IDD values in Table 79
Added VOH and VOL values in Table 79
Enhanced description of internal operating voltage
Added register bit allocation tables
Enhanced ESD HBM values
Fixed typos
PCF2129AT
PCF2127AT v.6
20130711
Product data sheet
-
PCF2127AT v.5
PCF2129AT v.5
20130212
Product data sheet
-
PCF2129AT v.4
PCF2129AT v.4
20121107
Product data sheet
-
PCF2129AT v.3
PCF2129AT v.3
20121004
Product data sheet
-
PCF2129AT v.2
PCF2129AT v.2
20100507
Product data sheet
-
PCF2129AT v.1
PCF2129AT v.1
20100113
Product data sheet
-
-
PCF2129T v.4
20130711
Product data sheet
-
PCF2129T v.3
PCF2129T v.3
20130212
Product data sheet
-
PCF2129T v.2
PCF2129T v.2
20121025
Product data sheet
-
PCF2129T v.1
PCF2129T v.1
20120618
Product data sheet
-
-
PCF2129T
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
79 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
23. Legal information
23.1 Data sheet status
Document status[1][2]
Product status[3]
Definition
Objective [short] data sheet
Development
This document contains data from the objective specification for product development.
Preliminary [short] data sheet
Qualification
This document contains data from the preliminary specification.
Product [short] data sheet
Production
This document contains the product specification.
[1]
Please consult the most recently issued document before initiating or completing a design.
[2]
The term ‘short data sheet’ is explained in section “Definitions”.
[3]
The product status of device(s) described in this document may have changed since this document was published and may differ in case of multiple devices. The latest product status
information is available on the Internet at URL http://www.nxp.com.
23.2 Definitions
Draft — The document is a draft version only. The content is still under
internal review and subject to formal approval, which may result in
modifications or additions. NXP Semiconductors does not give any
representations or warranties as to the accuracy or completeness of
information included herein and shall have no liability for the consequences of
use of such information.
Short data sheet — A short data sheet is an extract from a full data sheet
with the same product type number(s) and title. A short data sheet is intended
for quick reference only and should not be relied upon to contain detailed and
full information. For detailed and full information see the relevant full data
sheet, which is available on request via the local NXP Semiconductors sales
office. In case of any inconsistency or conflict with the short data sheet, the
full data sheet shall prevail.
Product specification — The information and data provided in a Product
data sheet shall define the specification of the product as agreed between
NXP Semiconductors and its customer, unless NXP Semiconductors and
customer have explicitly agreed otherwise in writing. In no event however,
shall an agreement be valid in which the NXP Semiconductors product is
deemed to offer functions and qualities beyond those described in the
Product data sheet.
23.3 Disclaimers
Limited warranty and liability — Information in this document is believed to
be accurate and reliable. However, NXP Semiconductors does not give any
representations or warranties, expressed or implied, as to the accuracy or
completeness of such information and shall have no liability for the
consequences of use of such information. NXP Semiconductors takes no
responsibility for the content in this document if provided by an information
source outside of NXP Semiconductors.
In no event shall NXP Semiconductors be liable for any indirect, incidental,
punitive, special or consequential damages (including - without limitation - lost
profits, lost savings, business interruption, costs related to the removal or
replacement of any products or rework charges) whether or not such
damages are based on tort (including negligence), warranty, breach of
contract or any other legal theory.
Notwithstanding any damages that customer might incur for any reason
whatsoever, NXP Semiconductors’ aggregate and cumulative liability towards
customer for the products described herein shall be limited in accordance
with the Terms and conditions of commercial sale of NXP Semiconductors.
Right to make changes — NXP Semiconductors reserves the right to make
changes to information published in this document, including without
limitation specifications and product descriptions, at any time and without
notice. This document supersedes and replaces all information supplied prior
to the publication hereof.
PCF2129
Product data sheet
Suitability for use — NXP Semiconductors products are not designed,
authorized or warranted to be suitable for use in life support, life-critical or
safety-critical systems or equipment, nor in applications where failure or
malfunction of an NXP Semiconductors product can reasonably be expected
to result in personal injury, death or severe property or environmental
damage. NXP Semiconductors and its suppliers accept no liability for
inclusion and/or use of NXP Semiconductors products in such equipment or
applications and therefore such inclusion and/or use is at the customer’s own
risk.
Applications — Applications that are described herein for any of these
products are for illustrative purposes only. NXP Semiconductors makes no
representation or warranty that such applications will be suitable for the
specified use without further testing or modification.
Customers are responsible for the design and operation of their applications
and products using NXP Semiconductors products, and NXP Semiconductors
accepts no liability for any assistance with applications or customer product
design. It is customer’s sole responsibility to determine whether the NXP
Semiconductors product is suitable and fit for the customer’s applications and
products planned, as well as for the planned application and use of
customer’s third party customer(s). Customers should provide appropriate
design and operating safeguards to minimize the risks associated with their
applications and products.
NXP Semiconductors does not accept any liability related to any default,
damage, costs or problem which is based on any weakness or default in the
customer’s applications or products, or the application or use by customer’s
third party customer(s). Customer is responsible for doing all necessary
testing for the customer’s applications and products using NXP
Semiconductors products in order to avoid a default of the applications and
the products or of the application or use by customer’s third party
customer(s). NXP does not accept any liability in this respect.
Limiting values — Stress above one or more limiting values (as defined in
the Absolute Maximum Ratings System of IEC 60134) will cause permanent
damage to the device. Limiting values are stress ratings only and (proper)
operation of the device at these or any other conditions above those given in
the Recommended operating conditions section (if present) or the
Characteristics sections of this document is not warranted. Constant or
repeated exposure to limiting values will permanently and irreversibly affect
the quality and reliability of the device.
Terms and conditions of commercial sale — NXP Semiconductors
products are sold subject to the general terms and conditions of commercial
sale, as published at http://www.nxp.com/profile/terms, unless otherwise
agreed in a valid written individual agreement. In case an individual
agreement is concluded only the terms and conditions of the respective
agreement shall apply. NXP Semiconductors hereby expressly objects to
applying the customer’s general terms and conditions with regard to the
purchase of NXP Semiconductors products by customer.
No offer to sell or license — Nothing in this document may be interpreted or
construed as an offer to sell products that is open for acceptance or the grant,
conveyance or implication of any license under any copyrights, patents or
other industrial or intellectual property rights.
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
80 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
Export control — This document as well as the item(s) described herein
may be subject to export control regulations. Export might require a prior
authorization from competent authorities.
Non-automotive qualified products — Unless this data sheet expressly
states that this specific NXP Semiconductors product is automotive qualified,
the product is not suitable for automotive use. It is neither qualified nor tested
in accordance with automotive testing or application requirements. NXP
Semiconductors accepts no liability for inclusion and/or use of
non-automotive qualified products in automotive equipment or applications.
In the event that customer uses the product for design-in and use in
automotive applications to automotive specifications and standards, customer
(a) shall use the product without NXP Semiconductors’ warranty of the
product for such automotive applications, use and specifications, and (b)
whenever customer uses the product for automotive applications beyond
NXP Semiconductors’ specifications such use shall be solely at customer’s
own risk, and (c) customer fully indemnifies NXP Semiconductors for any
liability, damages or failed product claims resulting from customer design and
use of the product for automotive applications beyond NXP Semiconductors’
standard warranty and NXP Semiconductors’ product specifications.
Translations — A non-English (translated) version of a document is for
reference only. The English version shall prevail in case of any discrepancy
between the translated and English versions.
23.4 Trademarks
Notice: All referenced brands, product names, service names and trademarks
are the property of their respective owners.
I2C-bus — logo is a trademark of NXP Semiconductors N.V.
24. Contact information
For more information, please visit: http://www.nxp.com
For sales office addresses, please send an email to: [email protected]
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
81 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
25. Tables
Table 1.
Table 2.
Table 3.
Table 4.
Table 5.
Table 6.
Table 7.
Table 8.
Table 9.
Table 10.
Table 11.
Table 12.
Table 13.
Table 14.
Table 15.
Table 16.
Table 17.
Table 18.
Table 19.
Table 20.
Table 21.
Table 22.
Table 23.
Table 24.
Table 25.
Table 26.
Table 27.
Table 28.
Table 29.
Table 30.
Table 31.
Table 32.
Table 33.
Table 34.
Ordering information . . . . . . . . . . . . . . . . . . . . . .2
Ordering options . . . . . . . . . . . . . . . . . . . . . . . . .2
Marking codes . . . . . . . . . . . . . . . . . . . . . . . . . .2
Pin description of PCF2129 . . . . . . . . . . . . . . . .5
Register overview . . . . . . . . . . . . . . . . . . . . . . .8
Control_1 - control and status register 1
(address 00h) bit allocation . . . . . . . . . . . . . . .10
Control_1 - control and status register 1
(address 00h) bit description . . . . . . . . . . . . . .10
Control_2 - control and status register 2
(address 01h) bit allocation . . . . . . . . . . . . . . . 11
Control_2 - control and status register 2
(address 01h) bit description . . . . . . . . . . . . . . 11
Control_3 - control and status register 3
(address 02h) bit allocation . . . . . . . . . . . . . . .12
Control_3 - control and status register 3
(address 02h) bit description . . . . . . . . . . . . . .12
CLKOUT_ctl - CLKOUT control register
(address 0Fh) bit allocation . . . . . . . . . . . . . . .12
CLKOUT_ctl - CLKOUT control register
(address 0Fh) bit description . . . . . . . . . . . . . .12
Temperature measurement period . . . . . . . . . .13
CLKOUT frequency selection . . . . . . . . . . . . . .14
Aging_offset - crystal aging offset register
(address 19h) bit allocation . . . . . . . . . . . . . . .14
Aging_offset - crystal aging offset register
(address 19h) bit description . . . . . . . . . . . . . .14
Frequency correction at 25 °C, typical . . . . . . .15
Power management control bit description. . . .16
Output pin BBS. . . . . . . . . . . . . . . . . . . . . . . . .21
Seconds - seconds and clock integrity
register (address 03h) bit allocation . . . . . . . . .25
Seconds - seconds and clock integrity
register (address 03h) bit description . . . . . . . .25
Seconds coded in BCD format . . . . . . . . . . . .26
Minutes - minutes register (address 04h)
bit allocation . . . . . . . . . . . . . . . . . . . . . . . . . . .26
Minutes - minutes register (address 04h)
bit description . . . . . . . . . . . . . . . . . . . . . . . . . .26
Hours - hours register (address 05h)
bit allocation . . . . . . . . . . . . . . . . . . . . . . . . . . .27
Hours - hours register (address 05h)
bit description . . . . . . . . . . . . . . . . . . . . . . . . .27
Days - days register (address 06h)
bit allocation . . . . . . . . . . . . . . . . . . . . . . . . . . .27
Days - days register (address 06h)
bit description . . . . . . . . . . . . . . . . . . . . . . . . . .27
Weekdays - weekdays register (address 07h)
bit allocation . . . . . . . . . . . . . . . . . . . . . . . . . . .28
Weekdays - weekdays register (address 07h)
bit description . . . . . . . . . . . . . . . . . . . . . . . . . .28
Weekday assignments . . . . . . . . . . . . . . . . . . .28
Months - months register (address 08h)
bit allocation . . . . . . . . . . . . . . . . . . . . . . . . . . .29
Months - months register (address 08h)
bit description . . . . . . . . . . . . . . . . . . . . . . . . . .29
PCF2129
Product data sheet
Table 35. Month assignments in BCD format . . . . . . . . . 29
Table 36. Years - years register (address 09h)
bit allocation . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Table 37. Years - years register (address 09h)
bit description. . . . . . . . . . . . . . . . . . . . . . . . . . 30
Table 38. Second_alarm - second alarm register
(address 0Ah) bit allocation . . . . . . . . . . . . . . 33
Table 39. Second_alarm - second alarm register
(address 0Ah) bit description . . . . . . . . . . . . . . 33
Table 40. Minute_alarm - minute alarm register
(address 0Bh) bit allocation . . . . . . . . . . . . . . 33
Table 41. Minute_alarm - minute alarm register
(address 0Bh) bit description . . . . . . . . . . . . . . 33
Table 42. Hour_alarm - hour alarm register
(address 0Ch) bit allocation . . . . . . . . . . . . . . 34
Table 43. Hour_alarm - hour alarm register
(address 0Ch) bit description . . . . . . . . . . . . . 34
Table 44. Day_alarm - day alarm register
(address 0Dh) bit allocation . . . . . . . . . . . . . . 34
Table 45. Day_alarm - day alarm register
(address 0Dh) bit description . . . . . . . . . . . . . . 34
Table 46. Weekday_alarm - weekday alarm register
(address 0Eh) bit allocation . . . . . . . . . . . . . . 35
Table 47. Weekday_alarm - weekday alarm register
(address 0Eh) bit description . . . . . . . . . . . . . . 35
Table 48. Watchdg_tim_ctl - watchdog timer control
register (address 10h) bit allocation . . . . . . . . 36
Table 49. Watchdg_tim_ctl - watchdog timer control
register (address 10h) bit description . . . . . . . 36
Table 50. Watchdg_tim_val - watchdog timer value
register (address 11h) bit allocation . . . . . . . . 36
Table 51. Watchdg_tim_val - watchdog timer value
register (address 11h) bit description . . . . . . . . 36
Table 52. Programmable watchdog timer . . . . . . . . . . . . 37
Table 53. Flag location in register Control_2 . . . . . . . . . . 38
Table 54. Example values in register Control_2 . . . . . . . 39
Table 55. Example to clear only AF (bit 4). . . . . . . . . . . . 39
Table 56. Example to clear only MSF (bit 7) . . . . . . . . . . 39
Table 57. Timestp_ctl - timestamp control register
(address 12h) bit allocation . . . . . . . . . . . . . . . 41
Table 58. Timestp_ctl - timestamp control register
(address 12h) bit description . . . . . . . . . . . . . . 41
Table 59. Sec_timestp - second timestamp register
(address 13h) bit allocation . . . . . . . . . . . . . . . 41
Table 60. Sec_timestp - second timestamp register
(address 13h) bit description . . . . . . . . . . . . . . 41
Table 61. Min_timestp - minute timestamp register
(address 14h) bit allocation . . . . . . . . . . . . . . . 42
Table 62. Min_timestp - minute timestamp register
(address 14h) bit description . . . . . . . . . . . . . . 42
Table 63. Hour_timestp - hour timestamp register
(address 15h) bit allocation . . . . . . . . . . . . . . . 42
Table 64. Hour_timestp - hour timestamp register
(address 15h) bit description . . . . . . . . . . . . . . 42
Table 65. Day_timestp - day timestamp register
(address 16h) bit allocation . . . . . . . . . . . . . . . 43
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
82 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
Table 66. Day_timestp - day timestamp register
(address 16h) bit description . . . . . . . . . . . . . .43
Table 67. Mon_timestp - month timestamp register
(address 17h) bit allocation . . . . . . . . . . . . . . .43
Table 68. Mon_timestp - month timestamp register
(address 17h) bit description . . . . . . . . . . . . . .43
Table 69. Year_timestp - year timestamp register
(address 18h) bit allocation . . . . . . . . . . . . . . .43
Table 70. Year_timestp - year timestamp register
(address 18h) bit description . . . . . . . . . . . . . .43
Table 71. Battery switch-over and timestamp. . . . . . . . . .44
Table 72. Effect of bits MI and SI on pin INT and
bit MSF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46
Table 73. First increment of time circuits after
stop release . . . . . . . . . . . . . . . . . . . . . . . . . . .50
Table 74. Interface selection input pin IFS . . . . . . . . . . . .51
Table 75. Serial interface . . . . . . . . . . . . . . . . . . . . . . . . .52
Table 76. Command byte definition . . . . . . . . . . . . . . . . .52
Table 77. I2C slave address byte . . . . . . . . . . . . . . . . . . .56
Table 78. Limiting values . . . . . . . . . . . . . . . . . . . . . . . . .58
Table 79. Static characteristics . . . . . . . . . . . . . . . . . . . .59
Table 80. Frequency characteristics . . . . . . . . . . . . . . . .64
Table 81. SPI-bus characteristics . . . . . . . . . . . . . . . . . .66
Table 82. I2C-bus characteristics . . . . . . . . . . . . . . . . . . .68
Table 83. Selection of Real-Time Clocks . . . . . . . . . . . . .75
Table 84. Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . .77
Table 85. Revision history . . . . . . . . . . . . . . . . . . . . . . . .79
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
83 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
26. Figures
Fig 1.
Fig 2.
Fig 3.
Fig 4.
Fig 5.
Fig 6.
Fig 7.
Fig 8.
Fig 9.
Fig 10.
Fig 11.
Fig 12.
Fig 13.
Fig 14.
Fig 15.
Fig 16.
Fig 17.
Fig 18.
Fig 19.
Fig 20.
Fig 21.
Fig 22.
Fig 23.
Fig 24.
Fig 25.
Fig 26.
Fig 27.
Fig 28.
Fig 29.
Fig 30.
Fig 31.
Fig 32.
Fig 33.
Fig 34.
Fig 35.
Fig 36.
Fig 37.
Fig 38.
Fig 39.
Fig 40.
Fig 41.
Fig 42.
Fig 43.
Block diagram of PCF2129 . . . . . . . . . . . . . . . . . .3
Pin configuration for PCF2129AT (SO20) . . . . . . .4
Pin configuration for PCF2129T (SO16) . . . . . . . .4
Position of the stubs from the package assembly
process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
Handling address registers . . . . . . . . . . . . . . . . . .6
Battery switch-over behavior in standard mode
with bit BIE set logic 1 (enabled) . . . . . . . . . . . . .18
Battery switch-over behavior in direct switching
mode with bit BIE set logic 1 (enabled) . . . . . . . .19
Battery switch-over circuit, simplified block
diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
Battery low detection behavior with bit BLIE set
logic 1 (enabled) . . . . . . . . . . . . . . . . . . . . . . . . .21
Typical driving capability of VBBS: (VBBS - VDD)
with respect to the output load current IBBS . . . . .22
Power failure event due to battery discharge:
reset occurs . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
Dependency between POR and oscillator . . . . . .24
Power-On Reset (POR) system. . . . . . . . . . . . . .24
Power-On Reset Override (PORO) sequence,
valid for both I2C-bus and SPI-bus . . . . . . . . . . .25
Data flow of the time function. . . . . . . . . . . . . . . .30
Access time for read/write operations . . . . . . . . .31
Alarm function block diagram. . . . . . . . . . . . . . . .32
Alarm flag timing diagram . . . . . . . . . . . . . . . . . .35
WD_CD set logic 1: watchdog activates an
interrupt when timed out . . . . . . . . . . . . . . . . . . .38
Timestamp detection with two push-buttons
on the TS pin (for example, for tamper detection)39
Interrupt block diagram . . . . . . . . . . . . . . . . . . . .45
INT example for SI and MI when TI_TP
is logic 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46
INT example for SI and MI when TI_TP
is logic 0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46
Example of shortening the INT pulse by
clearing the MSF flag . . . . . . . . . . . . . . . . . . . . . .47
AF timing diagram . . . . . . . . . . . . . . . . . . . . . . . .48
STOP bit functional diagram . . . . . . . . . . . . . . . .49
STOP bit release timing . . . . . . . . . . . . . . . . . . . .50
Interface selection . . . . . . . . . . . . . . . . . . . . . . . .51
SDI, SDO configurations . . . . . . . . . . . . . . . . . . .51
Data transfer overview . . . . . . . . . . . . . . . . . . . . .52
SPI-bus write example . . . . . . . . . . . . . . . . . . . . .53
SPI-bus read example . . . . . . . . . . . . . . . . . . . . .53
Bit transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .54
Definition of START and STOP conditions. . . . . .54
System configuration . . . . . . . . . . . . . . . . . . . . . .55
Acknowledgement on the I2C-bus . . . . . . . . . . . .55
Bus protocol, writing to registers . . . . . . . . . . . . .56
Bus protocol, reading from registers . . . . . . . . . .56
Device diode protection diagram of PCF2129 . . .57
IOL on pin SDA/CE . . . . . . . . . . . . . . . . . . . . . . . .61
IDD as a function of temperature . . . . . . . . . . . . .61
IDD as a function of VDD . . . . . . . . . . . . . . . . . . . .62
Typical IDD as a function of the power
PCF2129
Product data sheet
management settings . . . . . . . . . . . . . . . . . . . . . 63
Fig 44. Typical characteristic of frequency with respect to
temperature of PCF2129AT . . . . . . . . . . . . . . . . 65
Fig 45. Typical characteristic of frequency with respect to
temperature of PCF2129T . . . . . . . . . . . . . . . . . 65
Fig 46. SPI-bus timing. . . . . . . . . . . . . . . . . . . . . . . . . . . 67
Fig 47. I2C-bus timing diagram; rise and fall times refer to
30 % and 70 % . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Fig 48. General application diagram . . . . . . . . . . . . . . . . 70
Fig 49. Package outline SOT163-1 (SO20) of
PCF2129AT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Fig 50. Package outline SOT162-1 (SO16) of
PCF2129T. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
Fig 51. Footprint information for reflow soldering
of SOT163-1 (SO20) of PCF2129AT. . . . . . . . . . 73
Fig 52. Footprint information for reflow soldering
of SOT162-1 (SO16) of PCF2129T. . . . . . . . . . . 74
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
84 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
27. Contents
1
2
3
4
4.1
5
6
7
7.1
7.2
8
8.1
8.2
8.2.1
8.2.2
8.2.3
8.3
8.3.1
8.3.1.1
8.3.2
8.3.3
8.4
8.4.1
8.5
8.5.1
8.5.1.1
8.5.1.2
8.5.1.3
General description . . . . . . . . . . . . . . . . . . . . . . 1
Features and benefits . . . . . . . . . . . . . . . . . . . . 1
Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Ordering information . . . . . . . . . . . . . . . . . . . . . 2
Ordering options . . . . . . . . . . . . . . . . . . . . . . . . 2
Marking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Pinning information . . . . . . . . . . . . . . . . . . . . . . 4
Pinning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Pin description . . . . . . . . . . . . . . . . . . . . . . . . . 5
Functional description . . . . . . . . . . . . . . . . . . . 6
Register overview . . . . . . . . . . . . . . . . . . . . . . . 6
Control registers . . . . . . . . . . . . . . . . . . . . . . . 10
Register Control_1 . . . . . . . . . . . . . . . . . . . . . 10
Register Control_2 . . . . . . . . . . . . . . . . . . . . . 11
Register Control_3 . . . . . . . . . . . . . . . . . . . . . 12
Register CLKOUT_ctl . . . . . . . . . . . . . . . . . . . 12
Temperature compensated crystal oscillator . 13
Temperature measurement . . . . . . . . . . . . . . 13
OTP refresh . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Clock output . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Register Aging_offset . . . . . . . . . . . . . . . . . . . 14
Crystal aging correction . . . . . . . . . . . . . . . . . 14
Power management functions . . . . . . . . . . . . 16
Battery switch-over function . . . . . . . . . . . . . . 17
Standard mode . . . . . . . . . . . . . . . . . . . . . . . . 18
Direct switching mode . . . . . . . . . . . . . . . . . . 19
Battery switch-over disabled: only one power
supply (VDD) . . . . . . . . . . . . . . . . . . . . . . . . . . 19
8.5.1.4
Battery switch-over architecture . . . . . . . . . . . 20
8.5.2
Battery low detection function. . . . . . . . . . . . . 20
8.5.3
Battery backup supply . . . . . . . . . . . . . . . . . . 21
8.6
Oscillator stop detection function . . . . . . . . . . 22
8.7
Reset function . . . . . . . . . . . . . . . . . . . . . . . . 23
8.7.1
Power-On Reset (POR) . . . . . . . . . . . . . . . . . 23
8.7.2
Power-On Reset Override (PORO) . . . . . . . . 24
8.8
Time and date function . . . . . . . . . . . . . . . . . . 25
8.8.1
Register Seconds . . . . . . . . . . . . . . . . . . . . . . 25
8.8.2
Register Minutes. . . . . . . . . . . . . . . . . . . . . . . 26
8.8.3
Register Hours . . . . . . . . . . . . . . . . . . . . . . . . 27
8.8.4
Register Days . . . . . . . . . . . . . . . . . . . . . . . . . 27
8.8.5
Register Weekdays. . . . . . . . . . . . . . . . . . . . . 28
8.8.6
Register Months . . . . . . . . . . . . . . . . . . . . . . . 29
8.8.7
Register Years . . . . . . . . . . . . . . . . . . . . . . . . 30
8.8.8
Setting and reading the time. . . . . . . . . . . . . . 30
8.9
Alarm function. . . . . . . . . . . . . . . . . . . . . . . . . 32
8.9.1
8.9.2
8.9.3
8.9.4
8.9.5
8.9.6
8.10
8.10.1
8.10.2
8.10.3
8.10.4
Register Second_alarm . . . . . . . . . . . . . . . . .
Register Minute_alarm. . . . . . . . . . . . . . . . . .
Register Hour_alarm . . . . . . . . . . . . . . . . . . .
Register Day_alarm . . . . . . . . . . . . . . . . . . . .
Register Weekday_alarm. . . . . . . . . . . . . . . .
Alarm flag. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Timer functions. . . . . . . . . . . . . . . . . . . . . . . .
Register Watchdg_tim_ctl . . . . . . . . . . . . . . .
Register Watchdg_tim_val . . . . . . . . . . . . . . .
Watchdog timer function . . . . . . . . . . . . . . . .
Pre-defined timers: second and minute
interrupt . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8.10.5
Clearing flags . . . . . . . . . . . . . . . . . . . . . . . . .
8.11
Timestamp function . . . . . . . . . . . . . . . . . . . .
8.11.1
Timestamp flag. . . . . . . . . . . . . . . . . . . . . . . .
8.11.2
Timestamp mode . . . . . . . . . . . . . . . . . . . . . .
8.11.3
Timestamp registers. . . . . . . . . . . . . . . . . . . .
8.11.3.1 Register Timestp_ctl . . . . . . . . . . . . . . . . . . .
8.11.3.2 Register Sec_timestp. . . . . . . . . . . . . . . . . . .
8.11.3.3 Register Min_timestp . . . . . . . . . . . . . . . . . . .
8.11.3.4 Register Hour_timestp . . . . . . . . . . . . . . . . . .
8.11.3.5 Register Day_timestp. . . . . . . . . . . . . . . . . . .
8.11.3.6 Register Mon_timestp . . . . . . . . . . . . . . . . . .
8.11.3.7 Register Year_timestp . . . . . . . . . . . . . . . . . .
8.11.4
Dependency between Battery switch-over
and timestamp . . . . . . . . . . . . . . . . . . . . . . . .
8.12
Interrupt output, INT. . . . . . . . . . . . . . . . . . . .
8.12.1
Minute and second interrupts. . . . . . . . . . . . .
8.12.2
INT pulse shortening . . . . . . . . . . . . . . . . . . .
8.12.3
Watchdog timer interrupts . . . . . . . . . . . . . . .
8.12.4
Alarm interrupts . . . . . . . . . . . . . . . . . . . . . . .
8.12.5
Timestamp interrupts . . . . . . . . . . . . . . . . . . .
8.12.6
Battery switch-over interrupts . . . . . . . . . . . .
8.12.7
Battery low detection interrupts . . . . . . . . . . .
8.13
External clock test mode . . . . . . . . . . . . . . . .
8.14
STOP bit function . . . . . . . . . . . . . . . . . . . . . .
9
Interfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.1
SPI-bus interface . . . . . . . . . . . . . . . . . . . . . .
9.1.1
Data transmission . . . . . . . . . . . . . . . . . . . . .
9.2
I2C-bus interface . . . . . . . . . . . . . . . . . . . . . .
9.2.1
Bit transfer . . . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.2
START and STOP conditions. . . . . . . . . . . . .
9.2.3
System configuration . . . . . . . . . . . . . . . . . . .
9.2.4
Acknowledge . . . . . . . . . . . . . . . . . . . . . . . . .
9.2.5
I2C-bus protocol . . . . . . . . . . . . . . . . . . . . . . .
9.3
Bus communication and battery backup
operation . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10
Internal circuitry . . . . . . . . . . . . . . . . . . . . . . .
33
33
34
34
35
35
35
36
36
37
38
38
39
40
40
41
41
41
42
42
43
43
43
44
44
45
47
47
47
48
48
48
48
49
51
51
52
54
54
54
54
55
55
56
57
continued >>
PCF2129
Product data sheet
All information provided in this document is subject to legal disclaimers.
Rev. 7 — 19 December 2014
© NXP Semiconductors N.V. 2014. All rights reserved.
85 of 86
PCF2129
NXP Semiconductors
Accurate RTC with integrated quartz crystal for industrial applications
11
12
13
13.1
13.2
14
14.1
14.2
15
16
17
17.1
18
18.1
19
19.1
20
21
22
23
23.1
23.2
23.3
23.4
24
25
26
27
Safety notes . . . . . . . . . . . . . . . . . . . . . . . . . . .
Limiting values. . . . . . . . . . . . . . . . . . . . . . . . .
Static characteristics. . . . . . . . . . . . . . . . . . . .
Current consumption characteristics, typical .
Frequency characteristics. . . . . . . . . . . . . . . .
Dynamic characteristics . . . . . . . . . . . . . . . . .
SPI-bus timing characteristics . . . . . . . . . . . .
I2C-bus timing characteristics . . . . . . . . . . . . .
Application information. . . . . . . . . . . . . . . . . .
Package outline . . . . . . . . . . . . . . . . . . . . . . . .
Packing information . . . . . . . . . . . . . . . . . . . .
Tape and reel information . . . . . . . . . . . . . . . .
Soldering . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Footprint information. . . . . . . . . . . . . . . . . . . .
Appendix . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Real-Time Clock selection . . . . . . . . . . . . . . .
Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . .
References . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Revision history . . . . . . . . . . . . . . . . . . . . . . . .
Legal information. . . . . . . . . . . . . . . . . . . . . . .
Data sheet status . . . . . . . . . . . . . . . . . . . . . .
Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Disclaimers . . . . . . . . . . . . . . . . . . . . . . . . . . .
Trademarks. . . . . . . . . . . . . . . . . . . . . . . . . . .
Contact information. . . . . . . . . . . . . . . . . . . . .
Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
57
58
59
61
64
66
66
68
70
71
73
73
73
73
75
75
77
78
79
80
80
80
80
81
81
82
84
85
Please be aware that important notices concerning this document and the product(s)
described herein, have been included in section ‘Legal information’.
© NXP Semiconductors N.V. 2014.
All rights reserved.
For more information, please visit: http://www.nxp.com
For sales office addresses, please send an email to: [email protected]
Date of release: 19 December 2014
Document identifier: PCF2129