CY14B101KA, CY14B101MA 1-Mbit (128 K × 8/64 K × 16) nvSRAM with Real Time Clock Datasheet.pdf

CY14B101KA
CY14B101MA
1-Mbit (128K × 8/64K × 16) nvSRAM with
Real Time Clock
1-Mbit (128K × 8/64K × 16) nvSRAM with Real Time Clock
Features
1-Mbit nonvolatile static random access memory (nvSRAM)
❐ 25 ns and 45 ns access times
❐ Internally organized as 128K × 8 (CY14B101KA) or 64K × 16
(CY14B101MA)
❐ Hands off automatic STORE on power-down with only a small
capacitor
❐ STORE to QuantumTrap nonvolatile elements is initiated by
software, hardware, or AutoStore on power-down
❐ RECALL to SRAM initiated on power-up or by software
■ High reliability
❐ Infinite Read, Write, and RECALL cycles
❐ 1 million STORE cycles to QuantumTrap
❐ 20 year data retention
■ Real time clock (RTC)
❐ Full featured real time clock
❐ Watchdog timer
❐ Clock alarm with programmable interrupts
❐ Capacitor or battery backup for RTC
❐ Backup current of 0.35 µA (Typ)
■
Industry standard configurations
❐ Single 3 V +20%, –10% operation
❐ Industrial temperature
■
Packages
❐ 44-/54-pin thin small outline package (TSOP) Type II
❐ 48-pin shrink small outline package (SSOP)
■
Pb-free and restriction of hazardous substances (RoHS)
compliant
■
Functional Description
The Cypress CY14B101KA/CY14B101MA combines a 1-Mbit
nvSRAM with a full featured real time clock in a monolithic
integrated circuit. The embedded nonvolatile elements
incorporate QuantumTrap technology producing the world’s
most reliable nonvolatile memory. The SRAM is read and written
an infinite number of times, while independent nonvolatile data
resides in the nonvolatile elements.
The real time clock function provides an accurate clock with leap
year tracking and a programmable, high accuracy oscillator. The
alarm function is programmable for periodic minutes, hours,
days, or months alarms. There is also a programmable watchdog
timer for process control.
For a complete list of related documentation, click here.
Logic Block Diagram[1, 2, 3]
Quatrum
Trap
1024 X 1024
A5
A6
A7
R
O
W
A8
A9
A12
A13
A14
A15
A 16
D
E
C
O
D
E
R
STORE
VCA
VCC
P
VRTCbat
POWER
CONTROL
VRTCcap
RECALL
STATIC RAM
ARRAY
1024 X 1024
STORE/RECALL
CONTROL
SOFTWARE
DETECT
HSB
A14 - A2
DQ0
DQ1
DQ2
DQ3
DQ4
DQ5
DQ6
DQ7
DQ8
DQ9
DQ10
DQ11
RTC
I
N
P
U
T
B
U
F
F
E
R
S
Xout
Xin
INT
COLUMN I/O
MUX
A 16- A0
OE
COLUMN DEC
WE
DQ12
DQ13
CE
DQ14
BLE
A0 A1 A 2 A3 A 4 A10 A 11
DQ15
BHE
Notes
1. Address A0–A16 for × 8 configuration and Address A0–A15 for × 16 configuration.
2. Data DQ0–DQ7 for × 8 configuration and Data DQ0–DQ15 for × 16 configuration.
3. BHE and BLE are applicable for × 16 configuration only.
Cypress Semiconductor Corporation
Document Number: 001-42880 Rev. *O
•
198 Champion Court
•
San Jose, CA 95134-1709
•
408-943-2600
Revised February 22, 2016
CY14B101KA
CY14B101MA
Contents
Pinouts .............................................................................. 3
Pin Definitions .................................................................. 4
Device Operation .............................................................. 5
SRAM Read ................................................................ 5
SRAM Write ................................................................. 5
AutoStore Operation .................................................... 5
Hardware STORE (HSB) Operation ............................ 5
Hardware RECALL (Power-Up) .................................. 6
Software STORE ......................................................... 6
Software RECALL ....................................................... 6
Preventing AutoStore .................................................. 8
Data Protection ............................................................ 8
Real Time Clock Operation .............................................. 8
nvTIME Operation ....................................................... 8
Clock Operations ......................................................... 8
Reading the Clock ....................................................... 8
Setting the Clock ......................................................... 8
Backup Power ............................................................. 8
Stopping and Starting the Oscillator ............................ 9
Calibrating the Clock ................................................... 9
Alarm ........................................................................... 9
Watchdog Timer ........................................................ 10
Power Monitor ........................................................... 10
Interrupts ................................................................... 10
Flags Register ........................................................... 11
RTC External Components ....................................... 12
PCB Design Considerations for RTC ............................ 13
Layout requirements .................................................. 13
Maximum Ratings ........................................................... 18
Operating Range ............................................................. 18
DC Electrical Characteristics ........................................ 18
Document Number: 001-42880 Rev. *O
Data Retention and Endurance ..................................... 19
Capacitance .................................................................... 19
Thermal Resistance ........................................................ 19
AC Test Loads ................................................................ 20
AC Test Conditions ........................................................ 20
RTC Characteristics ....................................................... 20
AC Switching Characteristics ....................................... 21
SRAM Read Cycle .................................................... 21
SRAM Write Cycle ..................................................... 21
Switching Waveforms .................................................... 22
AutoStore/Power-Up RECALL ....................................... 25
Switching Waveforms .................................................... 25
Software Controlled STORE/RECALL Cycle ................ 26
Switching Waveforms .................................................... 26
Hardware STORE Cycle ................................................. 27
Switching Waveforms .................................................... 27
Truth Table for SRAM Operations ................................. 28
Truth Table for SRAM Operations ................................. 28
HSB must remain HIGH for SRAM operations. ............ 28
Ordering Information ...................................................... 29
Package Diagrams .......................................................... 30
Acronyms ........................................................................ 33
Document Conventions ................................................. 33
Units of Measure ....................................................... 33
Document History Page ................................................. 34
Sales, Solutions, and Legal Information ...................... 37
Worldwide Sales and Design Support ....................... 37
Products .................................................................... 37
PSoC® Solutions ...................................................... 37
Cypress Developer Community ................................. 37
Technical Support ..................................................... 37
Page 2 of 37
CY14B101KA
CY14B101MA
Pinouts
Figure 1. Pin Diagram – 44-pin, 54-pin TSOP II, and 48-pin SSOP
INT 1
[7]
NC
2
A0 3
A1 4
A2 5
A3 6
A4 7
CE 8
DQ0 9
DQ1 10
VCC 11
12
VSS
DQ2 13
DQ3 14
WE 15
A5 16
A6 17
A7 18
A8
19
A9
20
Xout
Xin
21
22
44-pin TSOP II
(× 8)
Top View
(not to scale)
VCAP
44
43
42
41
40
39
38
37
36
35
34
33
32
31
HSB
NC
[6]
NC
[5]
NC[4]
NC
A16
A15
OE
DQ7
DQ6
VSS
VCC
DQ5
DQ4
30
29
28
27
26
25
24
23
VCAP
A14
A13
DQ0
A3
A2
A12
A11
A10
A1
A0
DQ1
DQ2
Xout
Xin
VRTCcap
VRTCbat
A16
A14
A12
A7
A6
A5
INT
A4
NC
NC
NC
VSS
NC
VRTCbat
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
48-pin SSOP
(× 8)
Top View
(not to scale)
48
47
VCC
46
45
44
43
42
41
40
HSB
WE
A13
A8
A9
39
38
37
36
NC
NC
NC
VSS
NC
35
34
33
32
31
30
29
28
27
26
25
A15
NC
A11
VRTCcap
DQ6
OE
A10
CE
DQ7
DQ5
DQ4
DQ3
VCC
INT
[7]
NC
A0
A1
A2
A3
A4
CE
DQ0
DQ1
DQ2
DQ3
VCC
VSS
DQ4
DQ5
DQ6
DQ7
WE
A5
A6
A7
A8
A9
NC
Xout
Xin
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
54
53
52
51
50
49
54-pin TSOP II
(× 16)
Top View
(not to scale)
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
32
31
30
29
28
HSB
[6]
NC
[5]
NC
[4]
NC
A15
OE
BHE
BLE
DQ15
DQ14
DQ13
DQ12
VSS
VCC
DQ 11
DQ 10
DQ 9
DQ 8
VCAP
A14
A13
A12
A11
A10
NC
VRTCcap
VRTCbat
Notes
4. Address expansion for 2-Mbit. NC pin not connected to die.
5. Address expansion for 4-Mbit. NC pin not connected to die.
6. Address expansion for 8-Mbit. NC pin not connected to die.
7. Address expansion for 16-Mbit. NC pin not connected to die.
Document Number: 001-42880 Rev. *O
Page 3 of 37
CY14B101KA
CY14B101MA
Pin Definitions
Pin Name
A0–A16
I/O Type
Input
A0–A15
DQ0–DQ7
Address inputs. Used to select one of the 131,072 Bytes of the nvSRAM for × 8 configuration.
Address inputs. Used to select one of the 65,536 Words of the nvSRAM for × 16 configuration.
Input/Output Bidirectional data I/O Lines for × 8 configuration. Used as input or output lines depending on operation.
DQ0–DQ15
NC
Description
Bidirectional data I/O Lines for × 16 configuration. Used as input or output lines depending on operation.
No connect
No connects. This pin is not connected to the die.
Input
Write Enable input, Active LOW. When the chip is enabled and WE is LOW, data on the I/O pins is written
to the specific address location.
Input
Chip Enable input, Active LOW. When LOW, selects the chip. When HIGH, deselects the chip.
Input
Output Enable, Active LOW. The active LOW OE input enables the data output buffers during read cycles.
Deasserting OE HIGH causes the I/O pins to tristate.
BHE
Input
Byte High Enable, Active LOW. Controls DQ15–DQ8.
BLE
Xout[8]
Input
Byte Low Enable, Active LOW. Controls DQ7–DQ0.
Output
Xin[8]
Input
WE
CE
OE
Crystal connection. Drives crystal on start up.
Crystal connection. For 32.768 kHz crystal.
VRTCcap[8]
Power supply Capacitor supplied backup RTC supply voltage. Left unconnected if VRTCbat is used.
VRTCbat[8]
[8]
Power supply Battery supplied backup RTC supply voltage. Left unconnected if VRTCcap is used.
INT
Output
Interrupt output. Programmable to respond to the clock alarm, the watchdog timer, and the power
monitor. Also programmable to either active HIGH (push or pull) or LOW (open drain).
VSS
Ground
Ground for the device. Must be connected to the ground of the system.
VCC
HSB
VCAP
Power supply Power supply inputs to the device. 3.0 V +20%, –10%
Input/Output Hardware STORE Busy (HSB)
Output: Indicates busy status of nvSRAM when LOW. After each Hardware and Software STORE
operation, HSB is driven HIGH for a short time (tHHHD) with standard output high current and then a
weak internal pull-up resistor keeps this pin HIGH (external pull-up resistor connection optional).
Input: Hardware STORE implemented by pulling this pin LOW externally.
Power supply AutoStore capacitor. Supplies power to the nvSRAM during power loss to store data from SRAM to
nonvolatile elements.
Note
8. Left unconnected if RTC feature is not used.
Document Number: 001-42880 Rev. *O
Page 4 of 37
CY14B101KA
CY14B101MA
The CY14B101KA/CY14B101MA nvSRAM is made up of two
functional components paired in the same physical cell. These
are a SRAM memory cell and a nonvolatile QuantumTrap cell.
The SRAM memory cell operates as a standard fast static RAM.
Data in the SRAM is transferred to the nonvolatile cell (the
STORE operation), or from the nonvolatile cell to the SRAM (the
RECALL operation). Using this unique architecture, all cells are
stored and recalled in parallel. During the STORE and RECALL
operations SRAM read and write operations are inhibited. The
CY14B101KA/CY14B101MA supports infinite reads and writes
similar to a typical SRAM. In addition, it provides infinite RECALL
operations from the nonvolatile cells and up to 1 million STORE
operations. See Truth Table for SRAM Operations on page 28 for
a complete description of read and write modes.
SRAM Read
The CY14B101KA/CY14B101MA performs a read cycle
whenever CE and OE are LOW, and WE and HSB are HIGH.
The address specified on pins A0–16 or A0–15 determines which
of the 131,072 data bytes or 65,536 words of 16 bits each are
accessed. Byte enables (BHE, BLE) determine which bytes are
enabled to the output, in the case of 16-bit words. When the read
is initiated by an address transition, the outputs are valid after a
delay of tAA (read cycle #1). If the read is initiated by CE or OE,
the outputs are valid at tACE or at tDOE, whichever is later (read
cycle #2). The data output repeatedly responds to address
changes within the tAA access time without the need for
transitions on any control input pins. This remains valid until
another address change or until CE or OE is brought HIGH, or
WE or HSB is brought LOW.
SRAM Write
A write cycle is performed when CE and WE are LOW and HSB
is HIGH. The address inputs must be stable before entering the
write cycle and must remain stable until CE or WE goes HIGH at
the end of the cycle. The data on the common I/O pins IO0–7 are
written into the memory if it is valid tSD before the end of a
WE-controlled write, or before the end of an CE-controlled write.
The Byte Enable inputs (BHE, BLE) determine which bytes are
written, in the case of 16-bit words. It is recommended that OE
be kept HIGH during the entire write cycle to avoid data bus
contention on common I/O lines. If OE is left LOW, internal
circuitry turns off the output buffers tHZWE after WE goes LOW.
AutoStore Operation
The CY14B101KA/CY14B101MA stores data to the nvSRAM
using one of three storage operations. These three operations
are: Hardware STORE, activated by the HSB; Software STORE,
activated by an address sequence; AutoStore, on device
power-down. The AutoStore operation is a unique feature of
QuantumTrap technology and is enabled by default on the
CY14B101KA/CY14B101MA.
During a normal operation, the device draws current from VCC to
charge a capacitor connected to the VCAP pin. This stored
charge is used by the chip to perform a single STORE operation.
If the voltage on the VCC pin drops below VSWITCH, the part
Document Number: 001-42880 Rev. *O
automatically disconnects the VCAP pin from VCC. A STORE
operation is initiated with power provided by the VCAP capacitor.
Note If the capacitor is not connected to VCAP pin, AutoStore
must be disabled using the soft sequence specified in Preventing
AutoStore on page 8. In case AutoStore is enabled without a
capacitor on VCAP pin, the device attempts an AutoStore
operation without sufficient charge to complete the Store. This
corrupts the data stored in nvSRAM.
Figure 2. AutoStore Mode
VCC
0.1 uF
10 kOhm
Device Operation
VCC
WE
VCAP
VSS
VCAP
Figure 2 shows the proper connection of the storage capacitor
(VCAP) for automatic STORE operation. See DC Electrical
Characteristics on page 18 for the size of the VCAP. The voltage
on the VCAP pin is driven to VCC by a regulator on the chip. A
pull-up should be placed on WE to hold it inactive during
power-up. This pull-up is only effective if the WE signal is tristate
during power-up. Many MPUs tristate their controls on power-up.
This should be verified when using the pull-up. When the
nvSRAM comes out of power-on-RECALL, the MPU must be
active or the WE held inactive until the MPU comes out of reset.
To reduce unnecessary nonvolatile stores, AutoStore and
Hardware STORE operations are ignored unless at least one
write operation has taken place since the most recent STORE or
RECALL cycle. Software initiated STORE cycles are performed
regardless of whether a write operation has taken place.
Hardware STORE (HSB) Operation
The CY14B101KA/CY14B101MA provides the HSB pin to
control and acknowledge the STORE operations. The HSB pin
is used to request a Hardware STORE cycle. When the HSB pin
is driven LOW, the CY14B101KA/CY14B101MA conditionally
initiates a STORE operation after tDELAY. An actual STORE cycle
begins only if a write to the SRAM has taken place since the last
STORE or RECALL cycle. The HSB pin also acts as an open
drain driver (internal 100 k weak pull-up resistor) that is
internally driven LOW to indicate a busy condition when the
STORE (initiated by any means) is in progress.
Note After each Hardware and Software STORE operation HSB
is driven HIGH for a short time (tHHHD) with standard output high
current and then remains HIGH by internal 100 k pull-up
resistor.
Page 5 of 37
CY14B101KA
CY14B101MA
SRAM write operations that are in progress when HSB is driven
LOW by any means are given time (tDELAY) to complete before
the STORE operation is initiated. However, any SRAM write
cycles requested after HSB goes LOW are inhibited until HSB
returns HIGH. In case the write latch is not set, HSB is not driven
LOW by the CY14B101KA/CY14B101MA. But any SRAM read
and write cycles are inhibited until HSB is returned HIGH by MPU
or other external source.
During any STORE operation, regardless of how it is initiated,
the CY14B101KA/CY14B101MA continues to drive the HSB pin
LOW, releasing it only when the STORE is complete. Upon
completion of the STORE operation, the nvSRAM memory
access is inhibited for tLZHSB time after HSB pin returns HIGH.
Leave the HSB unconnected if it is not used.
Hardware RECALL (Power-Up)
During power-up or after any low power condition
(VCC< VSWITCH), an internal RECALL request is latched. When
VCC again exceeds the VSWITCH on power-up, a RECALL cycle
is automatically initiated and takes tHRECALL to complete. During
this time, the HSB pin is driven LOW by the HSB driver and all
reads and writes to nvSRAM are inhibited.
Software STORE
Data is transferred from the SRAM to the nonvolatile memory by
a software address sequence. The CY14B101KA/CY14B101MA
Software STORE cycle is initiated by executing sequential CE or
OE controlled read cycles from six specific address locations in
exact order. During the STORE cycle, an erase of the previous
nonvolatile data is first performed, followed by a program of the
nonvolatile elements. After a STORE cycle is initiated, further
input and output are disabled until the cycle is completed.
Because a sequence of reads from specific addresses is used
for STORE initiation, it is important that no other read or write
accesses intervene in the sequence, or the sequence is aborted
and no STORE or RECALL takes place.
Document Number: 001-42880 Rev. *O
To initiate the Software STORE cycle, the following read
sequence must be performed:
1. Read address 0x4E38 Valid READ
2. Read address 0xB1C7 Valid READ
3. Read address 0x83E0 Valid READ
4. Read address 0x7C1F Valid READ
5. Read address 0x703F Valid READ
6. Read address 0x8FC0 Initiate STORE cycle
The software sequence may be clocked with CE controlled reads
or OE controlled reads, with WE kept HIGH for all the six READ
sequences. After the sixth address in the sequence is entered,
the STORE cycle commences and the chip is disabled. HSB is
driven LOW. After the tSTORE cycle time is fulfilled, the SRAM is
activated again for the read and write operation.
Software RECALL
Data is transferred from the nonvolatile memory to the SRAM by
a software address sequence. A Software RECALL cycle is
initiated with a sequence of read operations in a manner similar
to the Software STORE initiation. To initiate the RECALL cycle,
the following sequence of CE or OE controlled read operations
must be performed:
1. Read address 0x4E38 Valid READ
2. Read address 0xB1C7 Valid READ
3. Read address 0x83E0 Valid READ
4. Read address 0x7C1F Valid READ
5. Read address 0x703F Valid READ
6. Read address 0x4C63 Initiate RECALL cycle
Internally, RECALL is a two step procedure. First, the SRAM data
is cleared. Next, the nonvolatile information is transferred into the
SRAM cells. After the tRECALL cycle time, the SRAM is again
ready for read and write operations. The RECALL operation
does not alter the data in the nonvolatile elements.
Page 6 of 37
CY14B101KA
CY14B101MA
Table 1. Mode Selection
CE
WE
OE
BHE, BLE[9]
A15–A0[10]
Mode
I/O
Power
H
X
X
X
X
Not selected
Output high Z
Standby
L
H
L
L
X
Read SRAM
Output data
Active
L
L
X
L
X
Write SRAM
Input data
Active
L
H
L
X
0x4E38
0xB1C7
0x83E0
0x7C1F
0x703F
0x8B45
Read SRAM
Read SRAM
Read SRAM
Read SRAM
Read SRAM
AutoStore
Disable
Output data
Output data
Output data
Output data
Output data
Output data
Active[11]
L
H
L
X
0x4E38
0xB1C7
0x83E0
0x7C1F
0x703F
0x4B46
Read SRAM
Read SRAM
Read SRAM
Read SRAM
Read SRAM
AutoStore
Enable
Output data
Output data
Output data
Output data
Output data
Output data
Active[11]
L
H
L
X
0x4E38
0xB1C7
0x83E0
0x7C1F
0x703F
0x8FC0
Read SRAM
Read SRAM
Read SRAM
Read SRAM
Read SRAM
Nonvolatile
STORE
Output data
Output data
Output data
Output data
Output data
Output high Z
Active ICC2[11]
L
H
L
X
0x4E38
0xB1C7
0x83E0
0x7C1F
0x703F
0x4C63
Read SRAM
Read SRAM
Read SRAM
Read SRAM
Read SRAM
Nonvolatile
RECALL
Output data
Output data
Output data
Output data
Output data
Output high Z
Active[11]
Notes
9. BHE and BLE are applicable for × 16 configuration only.
10. While there are 17 address lines on the CY14B101KA (16 address lines on the CY14B101MA), only the 13 address lines (A14–A2) are used to control software
modes. The remaining address lines are don’t care.
11. The six consecutive address locations must be in the order listed. WE must be HIGH during all six cycles to enable a nonvolatile cycle.
Document Number: 001-42880 Rev. *O
Page 7 of 37
CY14B101KA
CY14B101MA
Preventing AutoStore
The AutoStore function is disabled by initiating an AutoStore
disable sequence. A sequence of read operations is performed
in a manner similar to the Software STORE initiation. To initiate
the AutoStore disable sequence, the following sequence of CE
or OE controlled read operations must be performed:
1. Read address 0x4E38 Valid READ
2. Read address 0xB1C7 Valid READ
3. Read address 0x83E0 Valid READ
4. Read address 0x7C1F Valid READ
5. Read address 0x703F Valid READ
6. Read address 0x8B45 AutoStore Disable
The AutoStore is re-enabled by initiating an AutoStore enable
sequence. A sequence of read operations is performed in a
manner similar to the Software RECALL initiation.
To initiate the AutoStore enable sequence, the following
sequence of CE or OE controlled read operations must be
performed:
1. Read address 0x4E38 Valid READ
2. Read address 0xB1C7 Valid READ
3. Read address 0x83E0 Valid READ
4. Read address 0x7C1F Valid READ
5. Read address 0x703F Valid READ
6. Read address 0x4B46 AutoStore Enable
If the AutoStore function is disabled or re-enabled, a manual
STORE operation (Hardware or Software) issued to save the
AutoStore state through subsequent power-down cycles. The
part comes from the factory with AutoStore enabled and 0x00
written in all cells.
Data Protection
The CY14B101KA/CY14B101MA protects data from corruption
during low voltage conditions by inhibiting all externally initiated
STORE and write operations. The low voltage condition is
detected when VCC is less than VSWITCH. If the
CY14B101KA/CY14B101MA is in a write mode (both CE and
WE are LOW) at power-up, after a RECALL or STORE, the write
is inhibited until the SRAM is enabled after tLZHSB (HSB to output
active). This protects against inadvertent writes during power-up
or brown out conditions.
Real Time Clock Operation
nvTIME Operation
The CY14B101KA/CY14B101MA offers internal registers that
contain clock, alarm, watchdog, interrupt, and control functions.
RTC registers use the last 16 address locations of the SRAM.
Internal double buffering of the clock and timer information
registers prevents accessing transitional internal clock data
during a read or write operation. Double buffering also
circumvents disrupting normal timing counts or the clock
accuracy of the internal clock when accessing clock data. Clock
and alarm registers store data in BCD format.
RTC functionality is described with respect to CY14B101KA in
the following sections. The same description applies to
CY14B101MA, except for the RTC register addresses. The RTC
Document Number: 001-42880 Rev. *O
register addresses for CY14B101KA range from 0x1FFF0 to
0x1FFFF, while those for CY14B101MA range from 0x0FFF0 to
0x0FFFF. See Table 3 on page 14 and Table 4 on page 15 for a
detailed Register Map description.
Clock Operations
The clock registers maintain time up to 9,999 years in
one-second increments. The time can be set to any calendar
time and the clock automatically keeps track of days of the week
and month, leap years, and century transitions. There are eight
registers dedicated to the clock functions, which are used to set
time with a write cycle and to read time with a read cycle. These
registers contain the time of day in BCD format. Bits defined as
‘0’ are currently not used and are reserved for future use by
Cypress.
Reading the Clock
The double buffered RTC register structure reduces the chance
of reading incorrect data from the clock. Internal updates to the
CY14B101KA time keeping registers are stopped when the read
bit ‘R’ (in the flags register at 0x1FFF0) is set to ‘1’ before
reading clock data to prevent reading of data in transition.
Stopping the register updates does not affect clock accuracy.
When a read sequence of RTC device is initiated, the update of
the user timekeeping registers stops and does not restart until a
‘0’ is written to the read bit ‘R’ (in the flags register at 0x1FFF0).
After the end of read sequence, all the RTC registers are simultaneously updated within 20 ms.
Setting the Clock
A write access to the RTC device stops updates to the time
keeping registers and enables the time to be set when the write
bit ‘W’ (in the flags register at 0x1FFF0) is set to ‘1’. The correct
day, date, and time is then written into the registers and must be
in 24 hour BCD format. The time written is referred to as the
“Base Time”. This value is stored in nonvolatile registers and
used in the calculation of the current time. When the write bit ‘W’
is cleared by writing ‘0’ to it, the values of timekeeping registers
are transferred to the actual clock counters after which the clock
resumes normal operation.
If the time written to the timekeeping registers is not in the correct
BCD format, each invalid nibble of the RTC registers continue
counting to 0xF before rolling over to 0x0 after which RTC
resumes normal operation.
Note After ‘W’ bit is set to ‘0’, values written into the timekeeping,
alarm, calibration, and interrupt registers are transferred to the
RTC time keeping counters in tRTCp time. These counter values
must be saved to nonvolatile memory either by initiating a
Software/Hardware STORE or AutoStore operation. While
working in AutoStore disabled mode, perform a STORE
operation after tRTCp time while writing into the RTC registers for
the modifications to be correctly recorded.
Backup Power
The RTC in the CY14B101KA is intended for permanently
powered operation. The VRTCcap or VRTCbat pin is connected
depending on whether a capacitor or battery is chosen for the
application. When the primary power, VCC, fails and drops below
VSWITCH the device switches to the backup power supply.
Page 8 of 37
CY14B101KA
CY14B101MA
The clock oscillator uses very little current, which maximizes the
backup time available from the backup source. Regardless of the
clock operation with the primary source removed, the data stored
in the nvSRAM is secure, having been stored in the nonvolatile
elements when power was lost.
During backup operation, the CY14B101KA consumes a
0.35 µA (Typ) at room temperature. The user must choose
capacitor or battery values according to the application.
Note: If a battery is applied to VRTCbat pin prior to VCC, the chip
will draw high IBAK current. This occurs even if the oscillator is
disabled. In order to maximize battery life, VCC must be applied
before a battery is applied to VRTCbat pin.
Backup time values based on maximum current specifications
are shown in the following Table 2. Nominal backup times are
approximately two times longer.
Table 2. RTC Backup Time
Capacitor Value
Backup Time
0.1 F
72 hours
0.47 F
14 days
1.0 F
30 days
Using a capacitor has the obvious advantage of recharging the
backup source each time the system is powered up. If a battery
is used, a 3 V lithium is recommended and the CY14B101KA
sources current only from the battery when the primary power is
removed. However, the battery is not recharged at any time by
the CY14B101KA. The battery capacity must be chosen for total
anticipated cumulative down time required over the life of the
system.
Stopping and Starting the Oscillator
The OSCEN bit in the calibration register at 0x1FFF8 controls
the enable and disable of the oscillator. This bit is nonvolatile and
is shipped to customers in the “enabled” (set to ‘0’) state. To
preserve the battery life when the system is in storage, OSCEN
must be set to ‘1’. This turns off the oscillator circuit, extending
the battery life. If the OSCEN bit goes from disabled to enabled,
it takes approximately one second (two seconds maximum) for
the oscillator to start.
which may have become set when the system was first powered
on.
To reset OSCF, set the write bit ‘W’ (in the flags register at
0x1FFF0) to a ‘1’ to enable writes to the flags register . Write a
‘0’ to the OSCF bit and then reset the write bit to ‘0’ to disable
writes.
Calibrating the Clock
The RTC is driven by a quartz controlled crystal with a nominal
frequency of 32.768 kHz. Clock accuracy depends on the quality
of the crystal and calibration. The crystals available in market
typically have an error of +20 ppm to +35 ppm. However,
CY14B101KA employs a calibration circuit that improves the
accuracy to +1/–2 ppm at 25 °C. This implies an error of
+2.5 seconds to –5 seconds per month.
The calibration circuit adds or subtracts counts from the oscillator
divider circuit to achieve this accuracy. The number of pulses that
are suppressed (subtracted, negative calibration) or split (added,
positive calibration) depends upon the value loaded into the five
calibration bits found in Calibration register at 0x1FFF8. The
calibration bits occupy the five lower order bits in the Calibration
register. These bits are set to represent any value between ‘0’
and 31 in binary form. Bit D5 is a sign bit, where a ‘1’ indicates
positive calibration and a ‘0’ indicates negative calibration.
Adding counts speeds the clock up and subtracting counts slows
the clock down. If a binary ‘1’ is loaded into the register, it
corresponds to an adjustment of 4.068 or –2.034 ppm offset in
oscillator error, depending on the sign.
Calibration occurs within a 64-minute cycle. The first 62 minutes
in the cycle may, once every minute, have one second shortened
by 128 or lengthened by 256 oscillator cycles. If a binary ‘1’ is
loaded into the register, only the first two minutes of the
64-minute cycle are modified. If a binary 6 is loaded, the first 12
are affected, and so on. Therefore, each calibration step has the
effect of adding 512 or subtracting 256 oscillator cycles for every
125,829,120 actual oscillator cycles, that is, 4.068 or –2.034 ppm
of adjustment per calibration step in the Calibration register.
To determine the required calibration, the CAL bit in the flags
register (0x1FFF0) must be set to ‘1’. This causes the INT pin to
toggle at a nominal frequency of 512 Hz. Any deviation
measured from the 512 Hz indicates the degree and direction of
the required correction. For example, a reading of 512.01024 Hz
indicates a +20 ppm error. Hence, a decimal value of
–10 (001010b) must be loaded into the Calibration register to
offset this error.
While system power is off, if the voltage on the backup supply
(VRTCcap or VRTCbat) falls below their respective minimum level,
the oscillator may fail.The CY14B101KA has the ability to detect
oscillator failure when system power is restored. This is recorded
in the Oscillator Fail Flag (OSCF) of the flags register at the
address 0x1FFF0. When the device is powered on (VCC goes
above VSWITCH) the OSCEN bit is checked for the ‘enabled’
status. If the OSCEN bit is enabled and the oscillator is not active
within the first 5 ms, the OSCF bit is set to ‘1’. The system must
check for this condition and then write ‘0’ to clear the flag.
Alarm
Note that in addition to setting the OSCF flag bit, the time
registers are reset to the ‘Base Time’, which is the value last
written to the timekeeping registers. The control or calibration
registers and the OSCEN bit are not affected by the ‘oscillator
failed’ condition.
The alarm function compares user programmed values of alarm
time and date (stored in the registers 0x1FFF1-5) with the
corresponding time of day and date values. When a match
occurs, the alarm internal flag (AF) is set and an interrupt is
generated on INT pin if Alarm Interrupt Enable (AIE) bit is set.
The value of OSCF must be reset to ‘0’ when the time registers
are written for the first time. This initializes the state of this bit
There are four alarm match fields – date, hours, minutes, and
seconds. Each of these fields has a match bit that is used to
Document Number: 001-42880 Rev. *O
Note Setting or changing the Calibration register does not affect
the test output frequency.
To set or clear CAL, set the write bit ‘W’ (in the flags register at
0x1FFF0) to ‘1’ to enable writes to the flags register. Write a
value to CAL, and then reset the write bit to ‘0’ to disable writes.
Page 9 of 37
CY14B101KA
CY14B101MA
determine if the field is used in the alarm match logic. Setting the
match bit to ‘0’ indicates that the corresponding field is used in
the match process. Depending on the match bits, the alarm
occurs as specifically as once a month or as frequently as once
every minute. Selecting none of the match bits (all 1s) indicates
that no match is required and therefore, alarm is disabled.
Selecting all match bits (all 0s) causes an exact time and date
match.
There are two ways to detect an alarm event: by reading the AF
flag or monitoring the INT pin. The AF flag in the flags register
at 0x1FFF0 indicates that a date or time match has occurred.
The AF bit is set to ‘1’ when a match occurs. Reading the flags
register clears the alarm flag bit (and all others). A hardware
interrupt pin may also be used to detect an alarm event.
To set, clear or enable an alarm, set the ‘W’ bit (in flags register
– 0x1FFF0) to ‘1’ to enable writes to Alarm Registers. After
writing the alarm value, clear the ‘W’ bit back to ‘0’ for the
changes to take effect.
Note CY14B101KA requires the alarm match bit for seconds (bit
‘D7’ in Alarm-Seconds register 0x1FFF2) to be set to ‘0’ for
proper operation of Alarm Flag and Interrupt.
Watchdog Timer
The watchdog timer is a free running down counter that uses the
32 Hz clock (31.25 ms) derived from the crystal oscillator. The
oscillator must be running for the watchdog to function. It begins
counting down from the value loaded in the watchdog timer
register.
The timer consists of a loadable register and a free running
counter. On power-up, the watchdog time out value in register
0x1FFF7 is loaded into the counter load register. Counting
begins on power-up and restarts from the loadable value any
time the watchdog strobe (WDS) bit is set to ‘1’. The counter is
compared to the terminal value of ‘0’. If the counter reaches this
value, it causes an internal flag and an optional interrupt output.
You can prevent the time out interrupt by setting WDS bit to ‘1’
prior to the counter reaching ‘0’. This causes the counter to
reload with the watchdog time out value and to be restarted. As
long as the user sets the WDS bit prior to the counter reaching
the terminal value, the interrupt and WDT flag never occur.
New time out values are written by setting the watchdog write bit
to ‘0’. When the WDW is ‘0’, new writes to the watchdog time out
value bits D5–D0 are enabled to modify the time out value. When
WDW is ‘1’, writes to bits D5-D0 are ignored. The WDW function
enables a user to set the WDS bit without concern that the
watchdog timer value is modified. A logical diagram of the
watchdog timer is shown in Figure 3. Note that setting the
watchdog time out value to ‘0’ disables the watchdog function.
The output of the watchdog timer is the flag bit WDF that is set if
the watchdog is allowed to time out. If the watchdog interrupt
enable (WIE) bit in the interrupt register is set, a hardware
interrupt on INT pin is also generated on watchdog timeout. The
flag and the hardware interrupt are both cleared when the user
reads the flags registers.
Document Number: 001-42880 Rev. *O
Figure 3. Watchdog Timer Block Diagram
Clock
Divider
Oscillator
32,768 KHz
1 Hz
32 Hz
Counter
Zero
Compare
WDF
Load
Register
WDS
D
Q
WDW
Q
write to
Watchdog
Register
Watchdog
Register
Power Monitor
The CY14B101KA provides a power management scheme with
power fail interrupt capability. It also controls the internal switch
to backup power for the clock and protects the memory from low
VCC access. The power monitor is based on an internal bandgap
reference circuit that compares the VCC voltage to VSWITCH
threshold.
As described in the AutoStore Operation on page 5, when
VSWITCH is reached as VCC decays from power loss, a data
STORE operation is initiated from SRAM to the nonvolatile
elements, securing the last SRAM data state. Power is also
switched from VCC to the backup supply (battery or capacitor) to
operate the RTC oscillator.
When operating from the backup source, read and write
operations to nvSRAM are inhibited and the RTC functions are
not available to the user. The RTC clock continues to operate in
the background. The updated RTC time keeping registers data
are available to the user after VCC is restored to the device (see
AutoStore/Power-Up RECALL on page 25).
Interrupts
The CY14B101KA has flags register, interrupt register, and
interrupt logic that can signal interrupt to the microcontroller.
There are three potential sources for interrupt: watchdog timer,
power monitor, and alarm timer. Each of these can be individually
enabled to drive the INT pin by appropriate setting in the Interrupt
register (0x1FFF6). In addition, each has an associated flag bit
in the flags register (0x1FFF0) that the host processor uses to
determine the cause of the interrupt. The INT pin driver has two
bits that specify its behavior when an interrupt occurs.
An interrupt is raised only if both a flag is raised by one of the
three sources and the respective interrupt enable bit in interrupts
register is enabled (set to ‘1’). After an interrupt source is active,
two programmable bits, H/L and P/L, determine the behavior of
the output pin driver on INT pin. These two bits are located in the
interrupt register and can be used to drive level or pulse mode
output from the INT pin. In pulse mode, the pulse width is
internally fixed at approximately 200 ms. This mode is intended
to reset a host microcontroller. In the level mode, the pin goes to
its active polarity until the flags register is read by the user. This
Page 10 of 37
CY14B101KA
CY14B101MA
mode is used as an interrupt to a host microcontroller. The
control bits are summarized in the following section.
must be pulled up to Vcc by a 10 k resistor while using the
interrupt in active LOW mode.
Interrupts are only generated while working on normal power and
are not triggered when system is running in backup power mode.
Pulse/Level (P/L). When set to a ‘1’ and an interrupt occurs, the
INT pin is driven for approximately 200 ms. When P/L is set to a
‘0’, the INT pin is driven HIGH or LOW (determined by H/L) until
the flags register is read.
Note CY14B101KA generates valid interrupts only after the
Power-up RECALL sequence is completed. All events on INT pin
must be ignored for tHRECALL duration after power-up.
When an enabled interrupt source activates the INT pin, an
external host reads the flags registers to determine the cause.
All flags are cleared when the register is read. If the INT pin is
programmed for level mode, then the condition clears and the
INT pin returns to its inactive state. If the pin is programmed for
pulse mode, then reading the flag also clears the flag and the pin.
The pulse does not complete its specified duration if the flags
register is read. If the INT pin is used as a host reset, then the
flags register is not read during a reset.
Interrupt Register
Watchdog Interrupt Enable (WIE). When set to ‘1’, the
watchdog timer drives the INT pin and an internal flag when a
watchdog time out occurs. When WIE is set to ‘0’, the watchdog
timer only affects the WDF flag in Flags register .
Alarm Interrupt Enable (AIE). When set to ‘1’, the alarm match
drives the INT pin and an internal flag. When AIE is set to ‘0’, the
alarm match only affects the AF flag in Flags register .
Flags Register
Power Fail Interrupt Enable (PFE). When set to ‘1’, the power
fail monitor drives the pin and an internal flag. When PFE is set
to ‘0’, the power fail monitor only affects the PF flag in flags
register.
The flags register has three flag bits: WDF, AF, and PF, which
can be used to generate an interrupt. These flags are set by the
watchdog timeout, alarm match, or power fail monitor
respectively. The processor can either poll this register or enable
interrupts to be informed when a flag is set. These flags are
automatically reset when the register is read. The flags register
is automatically loaded with the value 0x00 on power-up (except
for the OSCF bit; see Stopping and Starting the Oscillator on
page 9).
High/Low (H/L). When set to a ‘1’, the INT pin is active HIGH
and the driver mode is push pull. The INT pin drives HIGH only
when VCC is greater than VSWITCH. When set to a ‘0’, the INT pin
is active LOW and the drive mode is open drain. The INT pin
Figure 4. Interrupt Block Diagram
WDF
Watchdog
Timer
WIE
P/L
VCC
PF
Power
Monitor
PFE
Pin
Driver
INT
VINT
H/L
WDF - Watchdog Timer Flag
WIE - Watchdog Interrupt
Enable
PF - Power Fail Flag
PFE - Power Fail Enable
AF - Alarm Flag
AIE - Alarm Interrupt Enable
P/L - Pulse Level
H/L - High/Low
VSS
AF
Clock
Alarm
AIE
Document Number: 001-42880 Rev. *O
Page 11 of 37
CY14B101KA
CY14B101MA
RTC External Components
The RTC requires connecting an external 32.768 kHz crystal and
C1, C2 load capacitance as shown in the Figure 5. The figure
shows the recommended RTC external component values. The
load capacitances C1 and C2 are inclusive of parasitic of the
printed circuit board (PCB). The PCB parasitic includes the
capacitance due to land pattern of crystal pads/pins, Xin/Xout
pads and copper traces connecting crystal and device pins.
Figure 5. RTC Recommended Component Configuration [12]
Recommended Values
Y1 = 32.768 kHz (12.5 pF)
C1 = 10 pF
C2 = 67 pF
Note: The recommended values for C1 and C2 include
board trace capacitance.
C1
Y1
C2
Xout
Xin
Note
12. For nonvolatile static random access memory (nvSRAM) real time clock (RTC) design guidelines and best practices, see application note AN61546.
Document Number: 001-42880 Rev. *O
Page 12 of 37
CY14B101KA
CY14B101MA
PCB Design Considerations for RTC
RTC crystal oscillator is a low current circuit with high impedance
nodes on their crystal pins. Due to lower timekeeping current of
RTC, the crystal connections are very sensitive to noise on the
board. Hence it is necessary to isolate the RTC circuit from other
signals on the board.
It is also critical to minimize the stray capacitance on the PCB.
Stray capacitances add to the overall crystal load capacitance
and therefore cause oscillation frequency errors. Proper
bypassing and careful layout are required to achieve the
optimum RTC performance.
■
Keep Xin and Xout trace width lesser than 8 mils. Wider trace
width leads to larger trace capacitance. The larger these bond
pads and traces are, the more likely it is that noise can couple
from adjacent signals.
■
Shield the Xin and Xout signals by providing a guard ring around
the crystal circuitry. This guard ring prevents noise coupling
from neighboring signals.
■
Take care while routing any other high speed signal in the
vicinity of RTC traces. The more the crystal is isolated from
other signals on the board, the less likely it is that noise is
coupled into the crystal. Maintain a minimum of 200 mil
separation between the Xin, Xout traces and any other high
speed signal on the board.
■
No signals should run underneath crystal components on the
same PCB layer.
Layout requirements
The board layout must adhere to (but not limited to) the following
guidelines during routing RTC circuitry. Following these guidelines help you achieve optimum performance from the RTC
design.
■
It is important to place the crystal as close as possible to the
Xin and Xout pins. Keep the trace lengths between the crystal
and RTC equal in length and as short as possible to reduce the
probability of noise coupling by reducing the length of the
antenna.
Create an isolated solid copper plane on adjacent PCB layer and
underneath the crystal circuitry to prevent unwanted noise
coupled from traces routed on the other signal layers of the PCB.
The local plane should be separated by at least 40 mils from the
neighboring plane on the same PCB layer. The solid plane
should be in the vicinity of RTC components only and its
perimeter should be kept equal to the guard ring perimeter.
Figure 6 shows the recommended layout for RTC circuit.
Figure 6. Recommended Layout for RTC
Top component layer: L1
Ground plane layer: L2
System ground
C1
Isolated ground plane on
layer 2 : L2
Guard ring - Top (Component)
layer: L1
Y1
C2
Via: Via connects to isolated
ground plane on L2
Document Number: 001-42880 Rev. *O
Via: Via connects to system ground
plane on L2
Page 13 of 37
CY14B101KA
CY14B101MA
Table 3. RTC Register Map [13, 14, 15]
BCD Format Data [14]
Register
CY14B101KA CY14B101MA
D7
D6
D5
0x1FFFF
0x0FFFF
0x1FFFE
0x0FFFE
0
0
0x1FFFD
0x0FFFD
0
0
0x1FFFC
0x0FFFC
0
0
0x1FFFB
0x0FFFB
0
0
0x1FFFA
0x0FFFA
0
0x1FFF9
0x0FFF9
0
0x1FFF8
0x0FFF8
OSCEN
(0)
0x1FFF7
0x0FFF7
WDS (0) WDW
(0)
0x1FFF6
0x0FFF6
WIE (0) AIE (0) PFE
(0)
0x1FFF5
0x0FFF5
0
10s
months
10s day of month
0
0
10s hours
10s seconds
0
0
10s alarm hours
0x1FFF2
0x0FFF2
M (1)
0x1FFF1
0x0FFF1
H/L (1)
Years: 00–99
Months
Months: 01–12
Day of month
Day of month: 01–31
Day of week
Day of week: 01–07
Hours
Hours: 00–23
Minutes
Minutes: 00–59
Seconds: 00–59
Calibration values [16]
Watchdog [16]
P/L
(0)
0
0
Alarm day
Interrupts [16]
Alarm, day of month:
01–31
Alarm hours
Alarm, hours: 00–23
10s alarm minutes
Alarm minutes
Alarm, minutes: 00–59
10s alarm seconds
Alarm, seconds
Alarm, seconds: 00–59
Centuries
Centuries: 00–99
10s centuries
WDF
Function/Range
Years
WDT (000000)
0
M (1)
M (1)
D0
Seconds
10s alarm date
0x0FFF4
D1
Calibration (00000)
Cal
sign
(0)
0
0x0FFF3
D2
0
10s minutes
M (1)
0x1FFF3
0x0FFF0
D3
10s years
0x1FFF4
0x1FFF0
D4
AF
PF
OSCF[17]
0
CAL
(0)
W (0)
R (0)
Flags [16]
Notes
13. Upper byte D15–D8 (CY14B101MA) of RTC registers are reserved for future use.
14. The unused bits of RTC registers are reserved for future use and should be set to ‘0’.
15. () designates values shipped from the factory.
16. This is a binary value, not a BCD value.
17. When user resets OSCF flag bit, the flags register will be updated after tRTCp time.
Document Number: 001-42880 Rev. *O
Page 14 of 37
CY14B101KA
CY14B101MA
Table 4. Register Map Detail
Register
CY14B101KA
CY14B101MA
0x1FFFF
0x0FFFF
Description
Time Keeping - Years
D7
D6
D5
D4
D3
D2
10s years
D1
D0
Years
Contains the lower two BCD digits of the year. Lower nibble (four bits) contains the value for years;
upper nibble (four bits) contains the value for 10s of years. Each nibble operates from 0 to 9. The
range for the register is 0–99.
0x1FFFE
0x0FFFE
Time Keeping - Months
D7
D6
D5
D4
0
0
0
10s month
D3
D2
D1
D0
Months
Contains the BCD digits of the month. Lower nibble (four bits) contains the lower digit and operates
from 0 to 9; upper nibble (one bit) contains the upper digit and operates from 0 to 1. The range for
the register is 1–12.
0x1FFFD
0x0FFFD
Time Keeping - Date
D7
D6
0
0
D5
D4
D3
10s day of month
D2
D1
D0
Day of month
Contains the BCD digits for the date of the month. Lower nibble (four bits) contains the lower digit
and operates from 0 to 9; upper nibble (two bits) contains the 10s digit and operates from 0 to 3.
The range for the register is 1–31. Leap years are automatically adjusted for.
0x1FFFC
0x0FFFC
Time Keeping - Day
D7
D6
D5
D4
D3
0
0
0
0
0
D2
D1
D0
Day of week
Lower nibble (three bits) contains a value that correlates to day of the week. Day of the week is a
ring counter that counts from 1 to 7 then returns to 1. The user must assign meaning to the day
value, because the day is not integrated with the date.
0x1FFFB
0x0FFFB
Time Keeping - Hours
D7
D6
0
0
D5
D4
D3
D2
10s hours
D1
D0
Hours
Contains the BCD value of hours in 24 hour format. Lower nibble (four bits) contains the lower digit
and operates from 0 to 9; upper nibble (two bits) contains the upper digit and operates from 0 to
2. The range for the register is 0–23.
0x1FFFA
0x0FFFA
Time Keeping - Minutes
D7
D6
0
D5
D4
D3
D2
10s minutes
D1
D0
Minutes
Contains the BCD value of minutes. Lower nibble (four bits) contains the lower digit and operates
from 0 to 9; upper nibble (three bits) contains the upper minutes digit and operates from 0 to 5.
The range for the register is 0–59.
0x1FFF9
0x0FFF9
Time Keeping - Seconds
D7
0
D6
D5
10s seconds
D4
D3
D2
D1
D0
Seconds
Contains the BCD value of seconds. Lower nibble (four bits) contains the lower digit and operates
from 0 to 9; upper nibble (three bits) contains the upper digit and operates from 0 to 5. The range
for the register is 0–59.
Document Number: 001-42880 Rev. *O
Page 15 of 37
CY14B101KA
CY14B101MA
Table 4. Register Map Detail (continued)
Register
CY14B101KA
CY14B101MA
0x1FFF8
0x0FFF8
Description
Calibration/Control
D7
D6
D5
OSCEN
0
Calibration
sign
D4
D3
D2
D1
D0
Calibration
OSCEN
Oscillator enable. When set to ‘1’, the oscillator is stopped. When set to ‘0’, the oscillator runs.
Disabling the oscillator saves battery or capacitor power during storage.
Calibration Sign
Determines if the calibration adjustment is applied as an addition (1) to or as a subtraction (0) from
the time-base.
Calibration
0x1FFF7
0x0FFF7
These five bits control the calibration of the clock.
WatchDog Timer
D7
D6
WDS
WDW
D5
D4
D3
D2
D1
D0
WDT
WDS
Watchdog strobe. Setting this bit to ‘1’ reloads and restarts the watchdog timer. Setting the bit to
‘0’ has no effect. The bit is cleared automatically after the watchdog timer is reset. The WDS bit is
write only. Reading it always returns a 0.
WDW
Watchdog write enable. Setting this bit to 1 disables any WRITE to the watchdog timeout value
(D5–D0). This allows the user to set the watchdog strobe bit without disturbing the timeout value.
Setting this bit to ‘0’ allows bits D5–D0 to be written to the watchdog register when the next write
cycle is complete. This function is explained in more detail in Watchdog Timer on page 10.
WDT
Watchdog timeout selection. The watchdog timer interval is selected by the 6-bit value in this
register. It represents a multiplier of the 32 Hz count (31.25 ms). The range of timeout value is
31.25 ms (a setting of 1) to 2 seconds (setting of 3 Fh). Setting the watchdog timer register to 0
disables the timer. These bits can be written only if the WDW bit was set to 0 on a previous cycle.
0x1FFF6
0x0FFF6
Interrupt Status/Control
D7
D6
D5
D4
D3
D2
D1
D0
WIE
AIE
PFE
0
H/L
P/L
0
0
WIE
Watchdog interrupt enable. When set to ‘1’ and a watchdog timeout occurs, the watchdog timer
drives the INT pin and the WDF flag. When set to ‘0’, the watchdog timeout affects only the WDF
flag.
AIE
Alarm interrupt enable. When set to ‘1’, the alarm match drives the INT pin and the AF flag. When
set to ‘0’, the alarm match only affects the AF flag.
PFE
Power fail enable. When set to ‘1’, the power fail monitor drives the INT pin and the PF flag. When
set to ‘0’, the power fail monitor affects only the PF flag.
0
Reserved for future use
H/L
High/Low. When set to ‘1’, the INT pin is driven active HIGH. When set to ‘0’, the INT pin is open
drain, active LOW.
P/L
Pulse/Level. When set to ‘1’, the INT pin is driven active (determined by H/L) by an interrupt source
for approximately 200 ms. When set to ‘0’, the INT pin is driven to an active level (as set by H/L)
until the flags register is read.
0x1FFF5
0x0FFF5
Alarm - Day
D7
D6
M
0
D5
D4
10s alarm date
D3
D2
D1
D0
Alarm date
Contains the alarm value for the date of the month and the mask bit to select or deselect the date
value.
M
Match. When this bit is set to ‘0’, the date value is used in the alarm match. Setting this bit to ‘1’
causes the match circuit to ignore the date value.
Document Number: 001-42880 Rev. *O
Page 16 of 37
CY14B101KA
CY14B101MA
Table 4. Register Map Detail (continued)
Register
CY14B101KA
CY14B101MA
0x1FFF4
0x0FFF4
Description
Alarm - Hours
D7
D6
M
0
D5
D4
D3
10s alarm hours
D2
D1
D0
Alarm hours
Contains the alarm value for the hours and the mask bit to select or deselect the hours value.
M
0x1FFF3
Match. When this bit is set to ‘0’, the hours value is used in the alarm match. Setting this bit to ‘1’
causes the match circuit to ignore the hours value.
0x0FFF3
Alarm - Minutes
D7
D6
M
D5
D4
D3
10s alarm minutes
D2
D1
D0
Alarm minutes
Contains the alarm value for the minutes and the mask bit to select or deselect the minutes value.
M
0x1FFF2
Match. When this bit is set to ‘0’, the minutes value is used in the alarm match. Setting this bit to
‘1’ causes the match circuit to ignore the minutes value.
0x0FFF2
Alarm - Seconds
D7
D6
M
D5
D4
D3
10s alarm seconds
D2
D1
D0
Alarm seconds
Contains the alarm value for the seconds and the mask bit to select or deselect the seconds’ value.
M
0x1FFF1
Match. When this bit is set to ‘0’, the seconds value is used in the alarm match. Setting this bit to
‘1’ causes the match circuit to ignore the seconds value.
0x0FFF1
Time Keeping - Centuries
D7
D6
D5
D4
D3
D2
10s centuries
D1
D0
Centuries
Contains the BCD value of centuries. Lower nibble contains the lower digit and operates from 0 to
9; upper nibble contains the upper digit and operates from 0 to 9. The range for the register is 0–99
centuries.
0x1FFF0
0x0FFF0
Flags
D7
D6
D5
D4
D3
D2
D1
D0
WDF
AF
PF
OSCF
0
CAL
W
R
WDF
Watchdog timer flag. This read only bit is set to ‘1’ when the watchdog timer is allowed to reach 0
without being reset by the user. It is cleared to 0 when the flags register is read or on power-up
AF
Alarm flag. This read only bit is set to ‘1’ when the time and date match the values stored in the
alarm registers with the match bits = 0. It is cleared when the flags register is read or on power-up.
PF
Power fail flag. This read only bit is set to ‘1’ when power falls below the power fail threshold
VSWITCH. It is cleared to 0 when the flags register is read or on power-up.
OSCF
Oscillator fail flag. Set to ‘1’ on power-up if the oscillator is enabled and not running in the first 5 ms
of operation. This indicates that RTC backup power failed and clock value is no longer valid. This
bit survives the power cycle and is never cleared internally by the chip. The user must check for
this condition and write '0' to clear this flag. When user resets OSCF flag bit, the bit will be updated
after tRTCp time.
CAL
Calibration mode. When set to ‘1’, a 512 Hz square wave is output on the INT pin. When set to ‘0’,
the INT pin resumes normal operation. This bit defaults to ‘0’ (disabled) on power-up.
W
Write enable: Setting the ‘W’ bit to ‘1’ freezes updates of the RTC registers. The user can then
write to RTC registers, alarm registers, calibration register, interrupt register and flags register.
Setting the ‘W’ bit to ‘0’ causes the contents of the RTC registers to be transferred to the time
keeping counters if the time has changed. This transfer process takes tRTCp time to complete. This
bit defaults to 0 on power-up.
R
Read enable: Setting ‘R’ bit to ‘1’, stops clock updates to user RTC registers so that clock updates
are not seen during the reading process. Set ‘R’ bit to ‘0’ to resume clock updates to the holding
register. Setting this bit does not require ‘W’ bit to be set to ‘1’. This bit defaults to 0 on power-up.
Document Number: 001-42880 Rev. *O
Page 17 of 37
CY14B101KA
CY14B101MA
Maximum Ratings
Exceeding maximum ratings may impair the useful life of the
device. These user guidelines are not tested.
Transient voltage (< 20 ns)
on any pin to ground potential ............ –2.0 V to VCC + 2.0 V
Package power dissipation capability (TA = 25 °C) ..... 1.0 W
Storage temperature ................................ –65 C to +150 C
Surface mount Pb soldering
temperature (3 seconds) ......................................... +260 C
Maximum accumulated storage time
DC output current (1 output at a time, 1s duration) .... 15 mA
At 150 C ambient temperature ...................... 1000 h
At 85 C ambient temperature .................... 20 Years
Static discharge voltage
(per MIL-STD-883, Method 3015) ......................... > 2001 V
Maximum junction temperature .................................. 150 C
Latch up current ............................................... ..... > 200 mA
Supply voltage on VCC relative to VSS ...........–0.5 V to 4.1 V
Operating Range
Voltage applied to outputs
in High Z state .................................... –0.5 V to VCC + 0.5 V
Input voltage ....................................... –0.5 V to VCC + 0.5 V
Range
Ambient Temperature
VCC
–40 C to +85 C
2.7 V to 3.6 V
Industrial
DC Electrical Characteristics
Over the Operating Range
Parameter
Description
Test Conditions
Min
Typ [18]
Max
Unit
VCC
Power supply voltage
2.7
3.0
3.6
V
ICC1
Average Vcc current
tRC = 25 ns
tRC = 45 ns
Values obtained without output loads
(IOUT = 0 mA)
–
–
70
52
mA
mA
ICC2
Average VCC current during
STORE
All inputs don’t care, VCC = Max.
Average current for duration tSTORE
–
–
10
mA
ICC3[18]
Average VCC current at
tRC= 200 ns, VCC(Typ), 25 °C
All inputs cycling at CMOS levels.
Values obtained without output loads
(IOUT = 0 mA).
–
35
–
mA
ICC4
Average VCAP current during
AutoStore cycle
All inputs don’t care. Average current for
duration tSTORE
–
–
5
mA
ISB
VCC standby current
CE > (VCC – 0.2 V).
VIN < 0.2 V or > (VCC – 0.2 V). W bit set to ‘0’.
Standby current level after nonvolatile cycle
is complete. Inputs are static. f = 0 MHz.
–
–
5
mA
IIX[19]
Input leakage current (except
HSB)
VCC = Max, VSS < VIN < VCC
–1
–
+1
µA
Input leakage current (for HSB)
VCC = Max, VSS < VIN < VCC
–100
–
+1
µA
–1
–
+1
µA
IOZ
Off state output leakage current VCC = Max, VSS < VOUT < VCC,
VIH
Input HIGH voltage
2.0
–
VCC + 0.5
V
VIL
Input LOW voltage
VSS – 0.5
–
0.8
V
VOH
Output HIGH voltage
IOUT = –2 mA
2.4
–
–
V
VOL
Output LOW voltage
IOUT = 4 mA
–
–
0.4
V
CE or OE > VIH or BHE/BLE > VIH or WE < VIL
Notes
18. Typical values are at 25 °C, VCC = VCC(Typ). Not 100% tested.
19. The HSB pin has IOUT = –2 µA for VOH of 2.4 V when both active HIGH and low drivers are disabled. When they are enabled standard VOH and VOL are valid. This
parameter is characterized but not tested.
Document Number: 001-42880 Rev. *O
Page 18 of 37
CY14B101KA
CY14B101MA
DC Electrical Characteristics (continued)
Over the Operating Range
Min
Typ [18]
Max
Unit
61
68
180
µF
–
–
VCC
V
Min
Unit
20
Years
1,000
K
Max
Unit
7
pF
Input capacitance (for BHE, BLE and HSB)
8
pF
Output capacitance (except HSB)
7
pF
Output capacitance (for HSB)
8
pF
Parameter
Description
Test Conditions
VCAP[20]
Storage capacitor
VVCAP[21, 22]
Between VCAP pin and VSS
Maximum voltage driven on VCAP VCC = Max
pin by the device
Data Retention and Endurance
Over the Operating Range
Parameter
Description
DATAR
Data retention
NVC
Nonvolatile STORE operations
Capacitance
Parameter [22]
CIN
COUT
Description
Test Conditions
Input capacitance (except BHE, BLE and HSB)
TA = 25 C, f = 1 MHz, VCC = VCC(Typ)
Thermal Resistance
Parameter [22]
Description
JA
Thermal resistance
(junction to ambient)
JC
Thermal resistance
(junction to case)
Test Conditions
48-pin
SSOP
44-pin
54-pin
TSOP II TSOP II
Test conditions follow standard test
methods and procedures for measuring
thermal impedance, in accordance with
EIA/JESD51.
37.47
41.74
36.4
C/W
24.71
11.90
10.13
C/W
Unit
Notes
20. Min VCAP value guarantees that there is a sufficient charge available to complete a successful AutoStore operation. Max VCAP value guarantees that the capacitor on
VCAP is charged to a minimum voltage during a Power-Up RECALL cycle so that an immediate power-down cycle can complete a successful AutoStore. Therefore it
is always recommended to use a capacitor within the specified min and max limits. See application note AN43593 for more details on VCAP options.
21. Maximum voltage on VCAP pin (VVCAP) is provided for guidance when choosing the VCAP capacitor. The voltage rating of the VCAP capacitor across the operating
temperature range should be higher than the VVCAP voltage.
22. These parameters are guaranteed by design and are not tested.
Document Number: 001-42880 Rev. *O
Page 19 of 37
CY14B101KA
CY14B101MA
AC Test Loads
Figure 7. AC Test Loads
577 
577 
3.0 V
3.0 V
R1
R1
OUTPUT
OUTPUT
R2
789 
30 pF
R2
789 
5 pF
AC Test Conditions
Input pulse levels ...................................................0 V to 3 V
Input rise and fall times (10%–90%) ........................... < 3 ns
Input and output timing reference levels ....................... 1.5 V
RTC Characteristics
Over the Operating Range
Parameter
Description
Min
Typ [23]
Max
Units
VRTCbat
RTC battery pin voltage
1.8
3.0
3.6
V
IBAK[24]
RTC backup current
(Refer Figure 5 for the recommended external
componets for RTC)
TA (Min)
–
–
0.35
µA
25 °C
–
0.35
–
µA
TA (Max)
–
–
0.5
µA
RTC capacitor pin voltage
TA (Min)
1.6
–
3.6
V
25 °C
1.5
3.0
3.6
V
TA (Max)
1.4
–
3.6
V
–
1
2
sec
VRTCcap
[25]
tOCS
RTC oscillator time to start
tRTCp
RTC processing time from end of ‘W’ bit set to ‘0’
RBKCHG
RTC backup capacitor charge current-limiting resistor
–
–
350
µs
350
–
850

Notes
23. These parameters are guaranteed by design and are not tested.
24. From either VRTCcap or VRTCbat.
25. If VRTCcap > 0.5 V or if no capacitor is connected to VRTCcap pin, the oscillator starts in tOCS time. If a backup capacitor is connected and VRTCcap < 0.5 V, the capacitor
must be allowed to charge to 0.5 V for oscillator to start.
Document Number: 001-42880 Rev. *O
Page 20 of 37
CY14B101KA
CY14B101MA
AC Switching Characteristics
Over the Operating Range
Parameters [26]
Cypress
Parameter
25 ns
Description
Alt Parameter
45 ns
Min
Max
Min
Max
Unit
SRAM Read Cycle
tACE
tACS
Chip enable access time
–
25
–
45
ns
[27]
tRC
Read cycle time
25
–
45
–
ns
tAA [28]
tAA
Address access time
–
25
–
45
ns
tDOE
tOE
Output enable to data valid
–
12
–
20
ns
tOHA[28]
tOH
Output hold after address change
3
–
3
–
ns
tLZCE [29, 30]
tLZ
Chip enable to output active
3
–
3
–
ns
tHZCE [29, 30]
tRC
tHZ
Chip disable to output inactive
–
10
–
15
ns
[29, 30]
tOLZ
Output enable to output active
0
–
0
–
ns
tHZOE [29, 30]
tOHZ
Output disable to output inactive
–
10
–
15
ns
tPU [29]
tPA
Chip enable to power active
0
–
0
–
ns
tPD [29]
tPS
Chip disable to power standby
–
25
–
45
ns
tDBE
–
Byte enable to data valid
–
12
–
20
ns
tLZBE[29]
tHZBE[29]
–
Byte enable to output active
0
–
0
–
ns
–
Byte disable to output inactive
–
10
–
15
ns
tLZOE
SRAM Write Cycle
tWC
tWC
Write cycle time
25
–
45
–
ns
tPWE
tWP
Write pulse width
20
–
30
–
ns
tSCE
tCW
Chip enable to end of write
20
–
30
–
ns
tSD
tDW
Data setup to end of write
10
–
15
–
ns
tHD
tDH
Data hold after end of write
0
–
0
–
ns
tAW
tAW
Address setup to end of write
20
–
30
–
ns
tSA
tAS
Address setup to start of write
0
–
0
–
ns
tWR
Address hold after end of write
0
–
0
–
ns
tWZ
Write enable to output disable
–
10
–
15
ns
tLZWE [29, 30]
tOW
Output active after end of write
3
–
3
–
ns
tBW
–
Byte enable to end of write
20
–
30
–
ns
tHA
tHZWE
[29, 30, 31]
Notes
26. Test conditions assume signal transition time of 3 ns or less, timing reference levels of VCC/2, input pulse levels of 0 to VCC(typ), and output loading of the specified
IOL/IOH and load capacitance shown in Figure 7 on page 20.
27. WE must be HIGH during SRAM read cycles.
28. Device is continuously selected with CE, OE, and BHE/BLE LOW.
29. These parameters are guaranteed by design and are not tested.
30. Measured ±200 mV from steady state output voltage.
31. If WE is low when CE goes low, the outputs remain in the high impedance state.
Document Number: 001-42880 Rev. *O
Page 21 of 37
CY14B101KA
CY14B101MA
Switching Waveforms
Figure 8. SRAM Read Cycle No. 1 (Address Controlled) [32, 33, 34]
tRC
Address
Address Valid
tAA
Data Output
Output Data Valid
Previous Data Valid
tOHA
Figure 9. SRAM Read Cycle No. 2 (CE and OE Controlled) [32, 34, 35]
Address
Address Valid
tRC
tHZCE
tACE
CE
tAA
tLZCE
tHZOE
tDOE
OE
tHZBE
tLZOE
tDBE
BHE, BLE
tLZBE
Data Output
High Impedance
Output Data Valid
tPU
ICC
Standby
tPD
Active
Notes
32. WE must be HIGH during SRAM read cycles.
33. Device is continuously selected with CE, OE, and BHE/BLE LOW.
34. HSB must remain HIGH during Read and Write cycles.
35. BHE and BLE are applicable for × 16 configuration only.
Document Number: 001-42880 Rev. *O
Page 22 of 37
CY14B101KA
CY14B101MA
Switching Waveforms (continued)
Figure 10. SRAM Write Cycle No. 1 (WE Controlled) [36, 37, 38, 39]
tWC
Address
Address Valid
tSCE
tHA
CE
tBW
BHE, BLE
tAW
tPWE
WE
tSA
tHD
tSD
Data Input
Input Data Valid
tLZWE
tHZWE
Data Output
High Impedance
Previous Data
Figure 11. SRAM Write Cycle No. 2 (CE Controlled) [36, 37, 38, 39]
tWC
Address Valid
Address
tSA
tSCE
tHA
CE
tBW
BHE, BLE
tPWE
WE
tSD
Input Data Valid
Data Input
Data Output
tHD
High Impedance
Notes
36. BHE and BLE are applicable for × 16 configuration only.
37. HSB must remain HIGH during read and write cycles.
38. If WE is LOW when CE goes LOW, the outputs remain in the high impedance state.
39. CE or WE must be VIH during address transitions.
Document Number: 001-42880 Rev. *O
Page 23 of 37
CY14B101KA
CY14B101MA
Switching Waveforms (continued)
Figure 12. SRAM Write Cycle #3 (BHE and BLE Controlled) [40, 41, 42, 43, 44]
(Not applicable for RTC register writes)
tWC
Address
Address Valid
tSCE
CE
tSA
tHA
tBW
BHE, BLE
tAW
tPWE
WE
tSD
Data Input
tHD
Input Data Valid
High Impedance
Data Output
Notes
40. If WE is LOW when CE goes LOW, the outputs remain in the high impedance state.
41. HSB must remain HIGH during read and write cycles.
42. CE or WE must be VIH during address transitions.
43. While there are 19 address lines on the CY14B101KA (18 address lines on the CY14B101MA), only 13 address lines (A14–A2) are used to control software modes.
The remaining address lines are don’t care.
44. Only CE and WE controlled writes to RTC registers are allowed. BLE pin must be held LOW before CE or WE pin goes LOW for writes to RTC register.
Document Number: 001-42880 Rev. *O
Page 24 of 37
CY14B101KA
CY14B101MA
AutoStore/Power-Up RECALL
Over the Operating Range
Parameter
CY14B101KA/CY14B101MA
Description
Min
Max
Unit
tHRECALL [45]
Power-Up RECALL duration
–
20
ms
tSTORE [46]
STORE cycle duration
–
8
ms
Time allowed to complete SRAM write cycle
–
25
ns
VSWITCH
Low voltage trigger level
–
2.65
V
tVCCRISE[48]
VCC rise time
150
–
µs
VHDIS[48]
HSB output disable voltage
–
1.9
V
tLZHSB[48]
tHHHD[48]
HSB to output active time
–
5
µs
HSB high active time
–
500
ns
tDELAY
[47]
Switching Waveforms
Figure 13. AutoStore or Power-Up RECALL [49]
VCC
VSWITCH
VHDIS
t VCCRISE
Note
46
tHHHD
Note
46
tSTORE
Note
tHHHD
50
tSTORE
50
Note
HSB OUT
tDELAY
tLZHSB
AutoStore
tLZHSB
tDELAY
POWERUP
RECALL
tHRECALL
tHRECALL
Read & Write
Inhibited
(RWI)
POWER-UP
RECALL
Read & Write
BROWN
OUT
AutoStore
POWER-UP
RECALL
Read & Write
POWER
DOWN
AutoStore
Notes
45. tHRECALL starts from the time VCC rises above VSWITCH.
46. If an SRAM write has not taken place since the last nonvolatile cycle, no AutoStore or Hardware STORE takes place
47. On a Hardware STORE and AutoStore initiation, SRAM write operation continues to be enabled for time tDELAY.
48. These parameters are guaranteed by design and are not tested.
49. Read and Write cycles are ignored during STORE, RECALL, and while VCC is below VSWITCH.
50. During power-up and power-down, HSB glitches when HSB pin is pulled up through an external resistor.
Document Number: 001-42880 Rev. *O
Page 25 of 37
CY14B101KA
CY14B101MA
Software Controlled STORE/RECALL Cycle
Over the Operating Range
Parameter [51, 52]
tRC
tSA
tCW
tHA
tRECALL
tSS [53, 54]
25 ns
Description
Min
25
0
20
0
–
–
STORE/RECALL initiation cycle time
Address setup time
Clock pulse width
Address hold time
RECALL duration
Soft sequence processing time
45 ns
Max
–
–
–
–
200
100
Min
45
0
30
0
–
–
Max
–
–
–
–
200
100
Unit
ns
ns
ns
ns
µs
µs
Switching Waveforms
Figure 14. CE & OE Controlled Software STORE/RECALL Cycle [52]
tRC
Address
tRC
Address #1
tSA
Address #6
tCW
tCW
CE
tHA
tSA
tHA
tHA
tHA
OE
tHHHD
HSB (STORE only)
tHZCE
tLZCE
t DELAY
55
Note
tLZHSB
High Impedance
tSTORE/tRECALL
DQ (DATA)
RWI
Figure 15. AutoStore Enable/Disable Cycle[52]
Address
tRC
tRC
Address #1
Address #6
tSA
CE
tCW
tCW
tHA
tSA
tHA
tHA
tHA
OE
tLZCE
tHZCE
tSS
55
Note
t DELAY
DQ (DATA)
RWI
Notes
51. The software sequence is clocked with CE controlled or OE controlled reads.
52. The six consecutive addresses must be read in the order listed in Table 1 on page 7. WE must be HIGH during all six consecutive cycles.
53. This is the amount of time it takes to take action on a soft sequence command. Vcc power must remain HIGH to effectively register command.
54. Commands such as STORE and RECALL lock out I/O until operation is complete which further increases this time. See the specific command.
55. DQ output data at the sixth read may be invalid since the output is disabled at tDELAY time.
Document Number: 001-42880 Rev. *O
Page 26 of 37
CY14B101KA
CY14B101MA
Hardware STORE Cycle
Over the Operating Range
Parameter
CY14B101KA/CY14B101MA
Description
Min
Max
Unit
tDHSB
HSB to output active time when write latch not set
–
25
ns
tPHSB
Hardware STORE pulse width
15
–
ns
Switching Waveforms
Figure 16. Hardware STORE Cycle [56]
Write latch set
tPHSB
HSB (IN)
tSTORE
tHHHD
tDELAY
HSB (OUT)
tLZHSB
DQ (Data Out)
RWI
Write latch not set
tPHSB
HSB pin is driven high to VCC only by Internal
100 kOhm resistor,
HSB driver is disabled
SRAM is disabled as long as HSB (IN) is driven low.
HSB (IN)
HSB (OUT)
tDELAY
tDHSB
tDHSB
RWI
Figure 17. Soft Sequence Processing [57, 58]
Soft Sequence
Command
Address
Address #1
tSA
Address #6
tCW
tSS
Soft Sequence
Command
Address #1
tSS
Address #6
tCW
CE
VCC
Notes
56. If an SRAM write has not taken place since the last nonvolatile cycle, no AutoStore or Hardware STORE takes place.
57. This is the amount of time it takes to take action on a soft sequence command. VCC power must remain HIGH to effectively register command.
58. Commands such as STORE and RECALL lock out I/O until operation is complete which further increases this time. See the specific command.
Document Number: 001-42880 Rev. *O
Page 27 of 37
CY14B101KA
CY14B101MA
Truth Table for SRAM Operations
HSB must remain HIGH for SRAM operations.
Table 5. Truth Table for × 8 Configuration
Inputs/Outputs[59]
CE
WE
OE
Mode
Power
H
X
X
High Z
Deselect/Power-down
Standby
L
H
L
Data out (DQ0–DQ7)
Read
Active
L
H
H
High Z
Output disabled
Active
L
L
X
Data in (DQ0–DQ7)
Write
Active
Truth Table for SRAM Operations
HSB must remain HIGH for SRAM operations.
Table 6. Truth Table for × 16 Configuration
CE
WE
OE
BHE[60]
BLE[60]
Inputs/Outputs[59]
H
X
X
X
X
High Z
Deselect/Power-down
Standby
L
X
X
H
H
High Z
Output disabled
Active
L
H
L
L
L
Data out (DQ0–DQ15)
Read
Active
L
H
L
H
L
Data out (DQ0–DQ7)
DQ8–DQ15 in High Z
Read
Active
L
H
L
L
H
Data out (DQ8–DQ15)
DQ0–DQ7 in High Z
Read
Active
L
H
H
L
L
High Z
Output disabled
Active
L
H
H
H
L
High Z
Output disabled
Active
L
H
H
L
H
High Z
Output disabled
Active
L
L
X
L
L
Data in (DQ0–DQ15)
Write
Active
L
L
X
H
L
Data in (DQ0–DQ7)
DQ8–DQ15 in High Z
Write
Active
L
L
X
L
H
Data in (DQ8–DQ15)
DQ0–DQ7 in High Z
Write
Active
Mode
Power
Notes
59. Data DQ0–DQ7 for × 8 configuration and Data DQ0–DQ15 for × 16 configuration.
60. BHE and BLE are applicable for × 16 configuration only.
Document Number: 001-42880 Rev. *O
Page 28 of 37
CY14B101KA
CY14B101MA
Ordering Information
Cypress offers other versions of this type of product in many different configurations and features. The below table contains only the
list of parts that are currently available. For a complete listing of all options, visit the Cypress website at www.cypress.com and see
the product summary page at http://www.cypress.com/products or contact your local sales representative. Cypress maintains a
worldwide network of offices, solution centers, manufacturer's representatives and distributors. To find the office closest to you, visit
us at http://www.cypress.com/go/datasheet/offices.
Speed
(ns)
25
45
Ordering Code
Package
Diagram
CY14B101KA-ZS25XIT
51-85087 44-pin TSOP II
CY14B101KA-ZS25XI
51-85087 44-pin TSOP II
CY14B101KA-SP25XIT
51-85061 48-pin SSOP
CY14B101KA-SP25XI
51-85061 48-pin SSOP
CY14B101KA-ZS45XIT
51-85087 44-pin TSOP II
CY14B101KA-ZS45XI
51-85087 44-pin TSOP II
CY14B101KA-SP45XIT
51-85061 48-pin SSOP
CY14B101KA-SP45XI
51-85061 48-pin SSOP
Package Type
Operating Range
Industrial
All the above parts are Pb-free.
Ordering Code Definitions
CY 14 B 101 K A - ZS 25 X I T
Option:
T - Tape and Reel
Blank - Std.
Pb-free
Temperature:
I - Industrial (–40 to 85 °C)
Speed:
25 - 25 ns
45 - 45 ns
Package:
Die revision:
Blank - No Rev
A - First Rev
ZS - 44-pin TSOP II
SP - 48-pin SSOP
Data Bus:
K - × 8 + RTC
M - × 16 + RTC
Voltage:
B - 3.0 V
Density:
101 - 1 Mb
14 - nvSRAM
Cypress
Document Number: 001-42880 Rev. *O
Page 29 of 37
CY14B101KA
CY14B101MA
Package Diagrams
Figure 18. 44-pin TSOP II Package Outline, 51-85087
51-85087 *E
Document Number: 001-42880 Rev. *O
Page 30 of 37
CY14B101KA
CY14B101MA
Package Diagrams (continued)
Figure 19. 54-pin TSOP II (22.4 × 11.84 × 1.0 mm) Package Outline, 51-85160
51-85160 *E
Document Number: 001-42880 Rev. *O
Page 31 of 37
CY14B101KA
CY14B101MA
Package Diagrams (continued)
Figure 20. 48-pin SSOP (300 Mils) Package Outline, 51-85061
51-85061 *F
Document Number: 001-42880 Rev. *O
Page 32 of 37
CY14B101KA
CY14B101MA
Acronyms
Acronym
Document Conventions
Description
Units of Measure
BCD
binary coded decimal
BHE
byte high enable
°C
Degrees Celsius
BLE
byte low enable
F
farads
CE
CMOS
chip enable
Hz
hertz
complementary metal oxide semiconductor
kbit
1024 bits
EIA
electronic industries alliance
kHz
kilohertz
HSB
I/O
hardware store busy
k
kilohms
input/output
MHz
megahertz
nvSRAM
nonvolatile static random access memory
µA
microamperes
OE
RoHS
output enable
µF
microfarads
restriction of hazardous substances
µs
microseconds
RWI
read and write inhibited
mA
milliamperes
RTC
real time clock
ms
milliseconds
SRAM
static random access memory
ns
nanoseconds
SSOP
shrink small outline package

ohms
TSOP
thin small outline package
%
percent
WE
write enable
pF
picofarads
ppm
parts per million
V
volts
W
watts
Document Number: 001-42880 Rev. *O
Symbol
Unit of Measure
Page 33 of 37
CY14B101KA
CY14B101MA
Document History Page
Document Title: CY14B101KA/CY14B101MA, 1-Mbit (128K × 8/64K × 16) nvSRAM with Real Time Clock
Document Number: 001-42880
Rev.
ECN No.
Submission
Date
Orig. of
Change
**
2050747
See ECN
UNC /
PYRS
*A
2607447
11/18/2008
GVCH /
AESA
Document Number: 001-42880 Rev. *O
Description of Change
New data sheet.
Removed 15 ns access speed, updated “Features”, added CY14B101MA
(x16) part, changed title to “CY14B101KA/CY14B101MA,
1-Mbit (128K x 8/64K x 16) nvSRAM with Real-Time-Clock”.
Added 54-pin TSOP II package related information, updated Logic block
diagram, added footnote 1 and 2.
Pin definition: Updated WE, HSB and NC pin description.
Page 4: Updated SRAM READ, SRAM WRITE, Autostore operation
description, Page 4: Updated Software store and software recall description
Updated Figure 2, Page 4: Updated Hardware store operation and Hardware
RECALL (Power up) description
Footnote 1 and 10 referenced for Mode selection Table
Added footnote 10, updated footnote 8 and 9
Page 6: updated Data protection description
Page 6: Updated starting and stopping the oscillator description
Page 7: Updated Calibrating the clock description
Page 8: Added Flags register
Updated table 4, added footnote 12 and 13
Updated Register map detail Table 5
Maximum Ratings: Added Max. Accumulated storage time
Changed Output short circuit current parameter name to DC output current
Changed ICC2 from 6 mA to 10 mA
Changed ICC3 from 15 mA to 35 mA
Changed ICC4 from 6 mA to 5 mA
Changed ISB from 3 mA to 5 mA
Added IIX for HSB
Updated ICC1, ICC3, ISB and IOZ Test conditions
Changed VCAP voltage min value from 68uF to 61uF
Added VCAP voltage max value to 180uF
Updated footnote 14 and 15, added footnote 16
Added Data retention and Endurance Table
Added thermal resistance value to 44/54 TSOP II packages
Updated Input Rise and Fall time in AC test Conditions
Changed VRTCcap min value from 1.2 to 1.5V for industrial Commercial
temperature
Changed VRTCcap min value from 2.7 to 3.6V for industrial Commercial
temperature
Updated RTC recommended component configuration values
Updated tOCS value for minimum and room temperature from 10 and 5sec to
2 and 1sec resp.
Referenced footnote 22 to tOHA parameter
Updated All switching waveforms
Updated footnote 22, added footnote 25
Added Figure 11 (SRAM WRITE CYCLE:BHE and BLE controlled)
Changed tSTORE max value from 15ms to 8ms
Updated tDELAY value
Added VHDIS, tHHHD and tLZHSB parameters
Updated footnote 29, added footnote 31 and 32
Software controlled STORE/RECALL Table: Changed tAS to tSA
Changed tGHAX to tHA, changed tHA value from 1ns to 0ns
Added Figure 14
Added tDHSB parameter, changed tHLHX to tPHSB
Updated tSS from 70 us to 100 us, added truth table for SRAM operations
Page 34 of 37
CY14B101KA
CY14B101MA
Document History Page (continued)
Document Title: CY14B101KA/CY14B101MA, 1-Mbit (128K × 8/64K × 16) nvSRAM with Real Time Clock
Document Number: 001-42880
Rev.
ECN No.
Submission
Date
Orig. of
Change
*A (cont.)
2607447
11/18/2008
GVCH /
AESA
Updated ordering information and part numbering nomenclature
*B
2654484
02/05/09
GVCH /
PYRS
Changed the data sheet from Advance information to Preliminary
Changed X1, X2 pin names to Xout, Xin respectively
Updated Real Time Clock operation description
Added footnotes 11 and 12
Added default values to RTC Register Map” table 3
Updated flag register description in Register Map Detail” table 4
Changed C1, C2 values to 21pF, 21pF respectively
Changed IBAK value from 350 nA to 450 nA at hot temperature
Changed VRTCcap typical value from 2.4V to 3.0V
Referenced Note 15 to parameters tLZCE, tHZCE, tLZOE, tHZOE, tLZBE, tLZWE,
tHZWEand tHZBE
Added footnote 24
Updated Figure 13
*C
2733909
07/09/09
GVCH /
AESA
Page 3; Added note to AutoStore Operation description
Page 4; Updated Hardware STORE (HSB) Operation description
Page 4; Updated Software STORE Operation description
Added best practices
Changed C1, C2 values to 10pF, 67pF respectively
Changed IBAK and VRTCcap parameter values
Added RBKCHG parameter
Updated VHDIS parameter description
Updated tDELAY parameter description
Updated footnote 28 and added footnote 35
*D
2757375
08/28/09
GVCH
Moved data sheet status from Preliminary to Final
Removed commercial temperature related specs
Removed 20ns access speed related specs
Updated Thermal resistance values for all the packages
Changed VRTCbat max value from 3.3V to 3.6V
Changed RBKCHG min value from 450to 350
Updated footnote 18
*E
2767333
01/06/10
GVCH /
PYRS
Changed STORE cycles to QuantumTrap from 200K to 1 Million
Added Data Retention and Endurance table
Updated IBAK RTC backup current spec unit from nA to A
Added Contents.
*F
2899937
03/26/10
GVCH
Added more clarity on HSB pin operation
Table 1: Added more clarity on BHE/BLE pin opeartion
Updated HSB pin operation in Switching Waveforms
Updated footnote 30
Updated Ordering Information table.
Updated package diagrams.
Updated copyright section.
*G
3134300
01/11/2011
GVCH
Updated Setting the Clock description
Added footnote 15
Updated ‘W’ bit desription in Register Map Detail table
Updated best practices
Updated input capacitance for BHE and BLE pin
Updated input and output capacitance for HSB pin
Added tRTCp parameter to RTC Characteristics table
Figure 13: Typo error fixed
Added Acronyms and Document Conventions.
Document Number: 001-42880 Rev. *O
Description of Change
Page 35 of 37
CY14B101KA
CY14B101MA
Document History Page (continued)
Document Title: CY14B101KA/CY14B101MA, 1-Mbit (128K × 8/64K × 16) nvSRAM with Real Time Clock
Document Number: 001-42880
Rev.
ECN No.
Submission
Date
Orig. of
Change
*H
3150308
01/21/2011
GVCH
No technical updates.
*I
3313245
07/14/2011
GVCH
Updated DC Electrical Characteristics (Added Note 19 and referred the same
note in VCAP parameter).
Updated AC Switching Characteristics (Added Note 26 and referred the same
note in Parameters).
*J
3500268
01/18/2012
GVCH
Added footnote 8 and 12.
*K
3659138
08/14/2012
GVCH
Updated Real Time Clock Operation (description).
Updated Maximum Ratings (Changed “Ambient temperature with power
applied” to “Maximum junction temperature”).
Updated DC Electrical Characteristics (Added VVCAP parameter and its details,
added Note 21 and referred the same note in VVCAP parameter, also referred
Note 22 in VVCAP parameter).
Updated Package Diagrams (spec 51-85160 (Changed revision from *C to
*D)).
*L
4047965
07/03/2013
GVCH
Updated Pin Definitions:
Updated HSB pin description (Added more clarity).
Updated Device Operation:
Updated AutoStore Operation (Removed sentence “The HSB signal is
monitored by the system to detect if an AutoStore cycle is in progress.”).
Updated Real Time Clock Operation:
Updated Backup Power (Added Note).
Added RTC External Components.
Moved Figure 5 from Flags Register section to RTC External Components
section.
Added PCB Design Considerations for RTC.
Updated Package Diagrams:
spec 51-85087 – Changed revision from *D to *E.
spec 51-85061 – Changed revision from *E to *F.
Updated to new template.
*M
4563189
11/06/2014
GVCH
Updated Functional Description:
Added “For a complete list of related documentation, click here.” at the end.
Updated Package Diagrams:
Spec 51-85160 - Changed revision from *D to *E
*N
4666625
02/20/2015
GVCH
No technical updates.
Completing Sunset Review.
*O
5146824
02/22/2016
GVCH
Updated Package Diagrams:
Fixed typo in Figure 20 (Updated with correct diagram for spec 51-85061 *F).
Updated to new template.
Document Number: 001-42880 Rev. *O
Description of Change
Page 36 of 37
CY14B101KA
CY14B101MA
Sales, Solutions, and Legal Information
Worldwide Sales and Design Support
Cypress maintains a worldwide network of offices, solution centers, manufacturer’s representatives, and distributors. To find the office
closest to you, visit us at Cypress Locations.
PSoC® Solutions
Products
Automotive
Clocks & Buffers
Interface
Lighting & Power Control
cypress.com/go/automotive
cypress.com/go/clocks
cypress.com/go/interface
cypress.com/go/powerpsoc
cypress.com/go/plc
Memory
PSoC
Touch Sensing
USB Controllers
Wireless/RF
cypress.com/go/memory
cypress.com/go/psoc
psoc.cypress.com/solutions
PSoC 1 | PSoC 3 | PSoC 4 | PSoC 5LP
Cypress Developer Community
Community | Forums | Blogs | Video | Training
Technical Support
cypress.com/go/support
cypress.com/go/touch
cypress.com/go/USB
cypress.com/go/wireless
© Cypress Semiconductor Corporation 2008-2016. This document is the property of Cypress Semiconductor Corporation and its subsidiaries, including Spansion LLC ("Cypress"). This document,
including any software or firmware included or referenced in this document ("Software"), is owned by Cypress under the intellectual property laws and treaties of the United States and other countries
worldwide. Cypress reserves all rights under such laws and treaties and does not, except as specifically stated in this paragraph, grant any license under its patents, copyrights, trademarks, or other
intellectual property rights. If the Software is not accompanied by a license agreement and you do not otherwise have a written agreement with Cypress governing the use of the Software, then Cypress
hereby grants you under its copyright rights in the Software, a personal, non-exclusive, nontransferable license (without the right to sublicense) (a) for Software provided in source code form, to modify
and reproduce the Software solely for use with Cypress hardware products, only internally within your organization, and (b) to distribute the Software in binary code form externally to end users (either
directly or indirectly through resellers and distributors), solely for use on Cypress hardware product units. Cypress also grants you a personal, non-exclusive, nontransferable, license (without the right
to sublicense) under those claims of Cypress's patents that are infringed by the Software (as provided by Cypress, unmodified) to make, use, distribute, and import the Software solely to the minimum
extent that is necessary for you to exercise your rights under the copyright license granted in the previous sentence. Any other use, reproduction, modification, translation, or compilation of the Software
is prohibited.
CYPRESS MAKES NO WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, WITH REGARD TO THIS DOCUMENT OR ANY SOFTWARE, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. Cypress reserves the right to make changes to this document without further notice. Cypress does not
assume any liability arising out of the application or use of any product or circuit described in this document. Any information provided in this document, including any sample design information or
programming code, is provided only for reference purposes. It is the responsibility of the user of this document to properly design, program, and test the functionality and safety of any application
made of this information and any resulting product. Cypress products are not designed, intended, or authorized for use as critical components in systems designed or intended for the operation of
weapons, weapons systems, nuclear installations, life-support devices or systems, other medical devices or systems (including resuscitation equipment and surgical implants), pollution control or
hazardous substances management, or other uses where the failure of the device or system could cause personal injury, death, or property damage ("Unintended Uses"). A critical component is any
component of a device or system whose failure to perform can be reasonably expected to cause the failure of the device or system, or to affect its safety or effectiveness. Cypress is not liable, in whole
or in part, and Company shall and hereby does release Cypress from any claim, damage, or other liability arising from or related to all Unintended Uses of Cypress products. Company shall indemnify
and hold Cypress harmless from and against all claims, costs, damages, and other liabilities, including claims for personal injury or death, arising from or related to any Unintended Uses of Cypress
products.
Cypress, the Cypress logo, Spansion, the Spansion logo, and combinations thereof, PSoC, CapSense, EZ-USB, F-RAM, and Traveo are trademarks or registered trademarks of Cypress in the United
States and other countries. For a more complete list of Cypress trademarks, visit cypress.com. Other names and brands may be claimed as property of their respective owners.
Document Number: 001-42880 Rev. *O
Revised February 22, 2016
Page 37 of 37