PERICOM PT7C4307

Preliminary Data Sheet
PT7C4307
Real-time Clock Module (I2C Bus)
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Product Features
Product Description
•
Using external 32.768kHz quartz crystal
The PT7C4307 serial real-time clock is a low-power
•
Supports I2C-Bus's high speed mode (400 kHz)
clock/calendar with a programmable square-wave output
•
Includes time (Hour/Minute/Second) and calendar
and 56 bytes of nonvolatile RAM.
(Year/Month/Date/Day) counter functions (BCD
code)
Address and data are transferred serially via a 2-wire,
•
Programmable square wave output signal
bidirectional bus. The clock/calendar provides seconds,
•
56-byte, battery-backed, nonvolatile (NV) RAM for
minutes, hours, day, date, month, and year information.
data storage
The date at the end of the month is automatically
Automatic power-fail detect and switch circuitry of
adjusted for months with fewer than 31 days, including
battery backup
corrections for leap year. The clock operates in either the
Consumes less than 500nA in battery backup mode
24-hour or 12-hour format with AM/PM indicator.
•
•
with oscillator running
The PT7C4307 has a built-in power sense circuit that
detects power failures and automatically switches to the
Ordering Information
battery supply.
Part Number
PT7C4307P
Package
8-Pin DIP
PT7C4307W
8-Pin SOIC
Table 1 shows the basic functions of PT7C4307. More
details are shown in section: overview of functions.
Note: Lead free package is available by adding “E” after each
part number. For example: PT7C4307PE.
Table 1. Basic functions of PT7C4307
Item
1
2
Function
Oscillator
Time
PT7C4307
Source: Crystal: 32.768kHz
√
Oscillator enable/disable
√
Oscillator fail detect
-
Time display
12-hour
√
24-hour
√
Century bit
3
Alarm interrupt
4
Programmable square wave output (Hz)
5
RAM
6
Battery backup
1, 4.096k, 8.192k, 32.768k
56×8
√
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Preliminary Data Sheet
PT7C4307
Real-time Clock Module (I2C Bus)
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Contents
Product Features ............................................................................................................................................................................... 1
Product Description .......................................................................................................................................................................... 1
Pin Assignment.................................................................................................................................................................................. 3
Pin Description .................................................................................................................................................................................. 3
Function Block .................................................................................................................................................................................. 4
Recommended Layout for Crystal .................................................................................................................................................. 4
Crystal Specifications ....................................................................................................................................................................... 4
Function Description......................................................................................................................................................................... 5
Overview of Functions .................................................................................................................................................................. 5
Registers......................................................................................................................................................................................... 6
Control and status register........................................................................................................................................................... 7
Time Counter .............................................................................................................................................................................. 8
Days of the week Counter ........................................................................................................................................................... 9
Calendar Counter ........................................................................................................................................................................ 9
2
I C Bus Interface............................................................................................................................................................................. 10
Overview of I2C-BUS .................................................................................................................................................................. 10
System Configuration ................................................................................................................................................................. 10
Starting and Stopping I2C Bus Communications ..................................................................................................................... 11
Slave Address .............................................................................................................................................................................. 13
Maximum Ratings........................................................................................................................................................................... 15
Recommended Operating Conditions ........................................................................................................................................... 15
DC Electrical Characteristics......................................................................................................................................................... 16
AC Electrical Characteristics......................................................................................................................................................... 17
Mechanical Information ................................................................................................................................................................. 18
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Preliminary Data Sheet
PT7C4307
Real-time Clock Module (I2C Bus)
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Pin Assignment
PT7C4307
1
X1
VCC
8
2
X2
SQW/OUT
7
3
VBAT
SCL
6
4
GND
SDA
5
DIP-8
SOIC-8
Pin Description
Pin no.
Pin
Type
Description
1
X1
I
Oscillator Circuit Input. Together with X2, 32.768kHz crystal is connected between them.
2
X2
O
Oscillator Circuit Output. Together with X1, 32.768kHz crystal is connected between them.
When 32.768kHz external input, X2 must be float.
6
SCL
I
Serial Clock Input. SCL is used to synchronize data movement on the I2C serial interface.
5
SDA
I/O
Serial Data Input/Output. SDA is the input/output pin for the 2-wire serial interface. The
SDA pin is open-drain output and requires an external pull-up resistor.
7
SQW/OUT
O
Square Wave/Output Driver. Open drain. Four frequencies selectable: 32.768k, 8.192k,
4.096k, 1Hz when SQWE bit is set to 1.
8
VCC
P
Power. Primary power for PT7C4307.
3
VBAT
P
+3V Battery Power.
4
GND
P
Ground.
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Preliminary Data Sheet
PT7C4307
Real-time Clock Module (I2C Bus)
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Function Block
PT7C4307
X1
CD
32.768
kHz
X2
Counter
Chain
OSC
Time Counter
(Sec,Min,Hour,Day,Date,Month,Year)
CG
SQW/OUT
Address
Decoder
Control Register
Address
Register
SCL
I /O
Interface
(I2C)
VCC
VBAT
56 x 8
RAM
Power Manager
SDA
Shift Registers
Recommended Layout for Crystal
PT7C4307
X1
32.768kHz
Crystal
X2
Local Ground plane
Layer 2
Guard Ring
(connect to gound)
Crystal Specifications
Parameter
Nominal Frequency
Series Resistance
Load Capacitance
Symbol
fO
ESR
CL
Min
Typ
32.768
Max
45
12.5
Unit
kHz
kΩ
pF
The crystal, traces and crystal input pins should be isolated from RF generating signals.
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Preliminary Data Sheet
PT7C4307
Real-time Clock Module (I2C Bus)
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Function Description
Overview of Functions
Clock function
CPU can read or write data including the year (last two digits), month, date, day, hour, minute, and second. Any (two-digit) year
that is a multiple of 4 is treated as a leap year and calculated automatically as such until the year 2099.
Programmable square wave output
A square wave output enable bit controls square wave output at pin 7. 4 frequencies are selectable: 1, 4.096k, 8.192k, 32.768k Hz.
Interface with CPU
Data is read and written via the I2C bus interface using two signal lines: SCL (clock) and SDA (data).
Since the output of the I/O pin SDA is open drain, a pull-up resistor should be used on the circuit board if the CPU output I/O is
also open drain.
The SCL's maximum clock frequency is 400 kHz, which supports the I2C bus's high-speed mode.
Oscillator enable/disable
Oscillator can be enabled or disabled by /EOSC bit. But time count chain does not shut down when the bit is logic 1.
RAM
56×8 nonvolatile RAM are available for customer use.
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Preliminary Data Sheet
PT7C4307
Real-time Clock Module (I2C Bus)
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Registers
Allocation of registers
Register definition
Addr.
(hex)*1
Function
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
00
Seconds (00-59)
/EOSC*2
S40
S20
S10
S8
S4
S2
S1
01
Minutes (00-59)
0
M40
M20
M10
M8
M4
M2
M1
02
Hours (00-23 / 01-12)
0
12, /24
H20 or
P, /A
H10
H8
H4
H2
H1
03
Days of the week (01-07)
0
0
0
0
0
W4
W2
W1
04
Dates (01-31)
0
0
D20
D10
D8
D4
D2
D1
05
Months (01-12)
0
0
0
MO10
MO8
MO4
MO2
MO1
06
Years (00-99)
Y80
Y40
Y20
Y10
Y8
Y4
Y2
Y1
07
Control*3
OUT*4
0
0
SQWE*5
0
0
RS1*6
RS0*6
-
-
-
-
-
-
-
-
08~3F
RAM*7
Caution points:
*1. PT7C4307 uses 6 bits for address. That is if write data to 41H, the data will be written to 01H address register.
*2. Oscillator Enable bit. When this bit is set to 1, oscillator is stopped but time count chain is still active.
*3. Control register was used to select SQW/OUT pin output square wave with one of 4 kinds of frequency or DC level.
*4. Control SQW/OUT pin output DC level when square wave is disabled.
*5. Square wave outputs enable at SQW/OUT pin.
*6. Square wave output frequency select.
*7. PT7C4307 has 56×8 static RAM for customer use. It is volatile RAM.
*8. All bits marked with "0" are read-only bits. Their value when read is always "0". All bits marked with "-" are customer using
space.
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Preliminary Data Sheet
PT7C4307
Real-time Clock Module (I2C Bus)
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Control and status register
Addr.
(hex)
Description
D7
D6
D5
D4
D3
D2
D1
D0
07
Control
(default)
OUT
0
0
0
0
0
SQWE
0
0
0
0
0
RS1
1
RS0
1
•
OUT
It controls the output level of the SQW/OUT pin when the square wave output is disabled.
OUT
Data
Description
0
When SQWE = 0, SQW/OUT pin output low.
1
When SQWE = 0, SQW/OUT pin output high.
Default
Read / Write
•
SQWE (Square Wave Enable)
This bit, when set to a logic 1, will enable the oscillator output. The frequency of the square wave output depends upon the value
of the RS0 and RS1 bits. With the square wave output set to 1Hz, the clock registers update on the falling edge of the square wave.
•
RS (Rate Select)
These bits control the frequency of the square wave output when the square wave output has been enabled.
RS1, RS0
Data
SQW output freq. (Hz)
00
1
01
4.096k
10
8.192k
11
32.768k
Read / Write
Default
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Preliminary Data Sheet
PT7C4307
Real-time Clock Module (I2C Bus)
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Time Counter
Time digit display (in BCD code):
• Second digits: Range from 00 to 59 and carried to minute digits when incremented from 59 to 00.
• Minute digits: Range from 00 to 59 and carried to hour digits when incremented from 59 to 00.
• Hour digits: See description on the /12, 24 bit. Carried to day and day-of-the-week digits when incremented from 11 p.m. to
12 a.m. or 23 to 00.
Addr.
(hex)
Description
D7
00
Seconds
(default)
/EOSC*
1
S40
S20
S10
S8
S4
S2
S1
Undefined Undefined Undefined Undefined Undefined Undefined Undefined
01
Minutes
(default)
0
0
M40
M20
M10
M8
M4
M2
M1
Undefined Undefined Undefined Undefined Undefined Undefined Undefined
02
Hours
(default)
0
0
12, /24 H20 or P,/A
H10
H8
H4
H2
H1
Undefined Undefined Undefined Undefined Undefined Undefined Undefined
D6
D5
D4
D3
D2
D1
D0
* Note: /EOSC bit must be written into 0 to start the time count.
•
12, /24 bit
This bit is used to select between 12-hour clock system and 24-hour clock system.
12, /24
Data
Description
0
24-hour system
1
12-hour system
Read / Write
This bit is used to select between 12-hour clock operation and 24-hour clock operation.
12, /24
Description
Hours register
0
24-hour time display
1
12-hour time display
24-hour clock
00
01
02
03
04
05
06
07
08
09
10
11
12-hour clock
52 ( AM 12 )
41 ( AM 01 )
42 ( AM 02 )
43 ( AM 03 )
44 ( AM 04 )
45 ( AM 05 )
46 ( AM 06 )
47 ( AM 07 )
48 ( AM 08 )
49 ( AM 09 )
50 ( AM 10 )
51 ( AM 11 )
24-hour clock
12
13
14
15
16
17
18
19
20
21
22
23
12-hour clock
72 ( PM 12)
61 ( PM 01 )
62 ( PM 02 )
63 ( PM 03 )
64 ( PM 04 )
65 ( PM 05 )
66 ( PM 06 )
67 ( PM 07 )
68 ( PM 08 )
69 ( PM 09 )
70 ( PM 10 )
71 ( PM 11 )
* Be sure to select between 12-hour and 24-hour clock operation before writing the time data.
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Preliminary Data Sheet
PT7C4307
Real-time Clock Module (I2C Bus)
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Days of the week Counter
The day counter is a divide-by-7 counter that counts from 01 to 07 and up 07 before starting again from 01. Values that
correspond to the day of week are user defined but must be sequential (i.e., if 1 equals Sunday, then 2 equals Monday, and so on).
Illogical time and date entries result in undefined operation.
Addr.
Description
D7
D6
D5
D4
D3
D2
D1
D0
(hex)
03
Days of the week
(default)
0
0
0
0
0
0
0
0
0
0
W4
W2
W1
Undefined Undefined Undefined
Calendar Counter
The data format is BCD format.
• Day digits: Range from 1 to 31 (for January, March, May, July, August, October and December).
Range from 1 to 30 (for April, June, September and November).
Range from 1 to 29 (for February in leap years).
Range from 1 to 28 (for February in ordinary years).
Carried to month digits when cycled to 1.
• Month digits: Range from 1 to 12 and carried to year digits when cycled to 1.
• Year digits: Range from 00 to 99 and 00, 04, 08, … , 92 and 96 are counted as leap years.
Addr.
(hex)
Description
D7
D6
04
Dates
(default)
0
0
0
0
05
Months
(default)
0
0
0
0
06
Years
(default)
D5
D4
D3
D2
D1
D0
D20
D10
D8
D4
D2
D1
Undefined Undefined Undefined Undefined Undefined Undefined
0
0
M10
M8
M4
M2
M1
Undefined Undefined Undefined Undefined Undefined
Y80
Y40
Y20
Y10
Y8
Y4
Y2
Y1
Undefined Undefined Undefined Undefined Undefined Undefined Undefined Undefined
Note: Any registered imaginary time should be replaced by correct time, otherwise it will cause the clock counter malfunction.
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Preliminary Data Sheet
PT7C4307
Real-time Clock Module (I2C Bus)
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I2C Bus Interface
Overview of I2C-BUS
The I2C bus supports bi-directional communications via two signal lines: the SDA (data) line and SCL (clock) line. A combination
of these two signals is used to transmit and receive communication start/stop signals, data signals, acknowledge signals, and so on.
Both the SCL and SDA signals are held at high level whenever communications are not being performed. The starting and
stopping of communications is controlled at the rising edge or falling edge of SDA while SCL is at high level. During data
transfers, data changes that occur on the SDA line are performed while the SCL line is at low level, and on the receiving side the
data is captured while the SCL line is at high level. In either case, the data is transferred via the SCL line at a rate of one bit per
clock pulse. The I2C bus device does not include a chip select pin such as is found in ordinary logic devices. Instead of using a
chip select pin, slave addresses are allocated to each device and the receiving device responds to communications only when its
slave address matches the slave address in the received data.
System Configuration
All ports connected to the I2C bus must be either open drain or open collector ports in order to enable AND connections to
multiple devices.
SCL and SDA are both connected to the VDD line via a pull-up resistance. Consequently, SCL and SDA are both held at high
level when the bus is released (when communication is not being performed).
Fig 1. System configuration
Vcc
RP
RP
SDA
SCL
Master
MCU
Slave
RTC
Other Peripheral
Device
Note: When there is only one master, the MCU is ready for driving SCL to "H" and R P of SCL may not required.
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Preliminary Data Sheet
PT7C4307
Real-time Clock Module (I2C Bus)
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Starting and Stopping I2C Bus Communications
Fig 2. Starting and stopping on I2C bus
1) START condition, repeated START condition, and STOP condition
a) START condition
SDA level changes from high to low while SCL is at high level
b) STOP condition
SDA level changes from low to high while SCL is at high level
c) Repeated START condition (RESTART condition)
In some cases, the START condition occurs between a previous START condition and the next STOP condition, in
which case the second START condition is distinguished as a RESTART condition. Since the required status is the same as for the
START condition, the SDA level changes from high to low while SCL is at high level.
2) Data Transfers and Acknowledge Responses during I2C-BUS Communication
a) Data transfers
Data transfers are performed in 8-bit (1 byte) units once the START condition has occurred. There is no limit on the amount
(bytes) of data that are transferred between the START condition and STOP condition.
The address auto increment function operates during both write and read operations.
Updating of data on the transmitter (transmitting side)'s SDA line is performed while the SCL line is at low level.
The receiver (receiving side) captures data while the SCL line is at high level.
*Note with caution that if the SDA data is changed while the SCL line is at high level, it will be treated as a START, RESTART,
or STOP condition.
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Preliminary Data Sheet
PT7C4307
Real-time Clock Module (I2C Bus)
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b) Data acknowledge response (ACK signal)
When transferring data, the receiver generates a confirmation response (ACK signal, low active) each time an 8-bit data segment
is received. If there is no ACK signal from the receiver, it indicates that normal communication has not been established. (This
does not include instances where the master device intentionally does not generate an ACK signal.)
Immediately after the falling edge of the clock pulse corresponding to the 8th bit of data on the SCL line, the transmitter releases
the SDA line and the receiver sets the SDA line to low (= acknowledge) level.
SCL from Master
1
8
2
SDA from transmitter
(sending side)
9
Release SDA
Low active
SDA from receiver
(receiving side)
ACK signal
After transmitting the ACK signal, if the Master remains the receiver for transfer of the next byte, the SDA is released at the
falling edge of the clock corresponding to the 9th bit of data on the SCL line. Data transfer resumes when the Master becomes the
transmitter.
When the Master is the receiver, if the Master does not send an ACK signal in response to the last byte sent from the slave, that
indicates to the transmitter that data transfer has ended. At that point, the transmitter continues to release the SDA and awaits a
STOP condition from the Master.
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Preliminary Data Sheet
PT7C4307
Real-time Clock Module (I2C Bus)
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Slave Address
The I2C bus device does not include a chip select pin such as is found in ordinary logic devices. Instead of using a chip select pin,
slave addresses are allocated to each device.
All communications begin with transmitting the [START condition] + [slave address (+ R/W specification)]. The receiving device
responds to this communication only when the specified slave address it has received matches its own slave address.
Slave addresses have a fixed length of 7 bits. See table for the details.
An R/W bit is added to each 7-bit slave address during 8-bit transfers.
Table
Slave address
R / W bit
Operation
Transfer data
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
Read
D1 h
1 (= Read)
1
1
0
1
0
0
0
Write
D0 h
0 (= Write)
I2C Bus’s Basic Transfer Format
S
Start indication
Sr
Restart indication
P
Stop indication
A
RTC Acknowledge
A
Master Acknowledge
1) Write via I2C bus
Slave address (7 bits)
S
1
Start
1
0
1
0
0
write
0
Slave address + write specification
A
Addr. setting
A
0
A
C
K
Address
Specifies the write start address.
PT0206(02/05)
A
C
K
bit
bit
bit
bit
bit
bit
bit
bit
7
6
5
4
3
2
1
0
Write data
A
P
A
C
K
Stop
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13
Preliminary Data Sheet
PT7C4307
Real-time Clock Module (I2C Bus)
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2) Read via I2C bus
a) Standard read
Slave address (7 bits)
S
1
Start
1
0
1
0
0
write
0
Slave address (7 bits)
1
1
0
1
0
0
A
C
K
Read
0
A
1
A
C
K
Restart
Slave address + read specification
b)
A
0
Slave address + write specification
Sr
Addr. setting
A
A
C
K
Address
Specifies the read start address.
bit
bit
bit
bit
bit
bit
bit
bit
7
6
5
4
3
2
1
0
Data read (1)
Data is read from the specified start
address and address auto increment.
A
A
C
K
bit
bit
bit
bit
bit
bit
bit
bit
7
6
5
4
3
2
1
0
Data read (2)
Address auto increment to set the
address for the next data to be read.
/A
P
N
O
Stop
A
C
K
Simplified read
Slave address (7 bits)
S
1
Start
1
0
1
0
0
Read
0
Slave address + read specification
A
bit
bit
bit
bit
bit
bit
bit
bit
7
6
5
4
3
2
1
0
A
C
K
Data read (1)
Data is read from the address pointed
by the internal address register and
address auto increment.
1
A
bit
bit
bit
bit
bit
bit
bit
bit
7
6
5
4
3
2
1
0
A
C
K
Data read (2)
Address register auto increment to set
the address for the next data to be
read.
/A
P
N
O
Stop
A
C
K
Note:
1. The above steps are an example of transfers of one or two bytes only. There is no limit to the number of bytes transferred
during actual communications.
2. 49H, 4AH are used as test mode address. Customer should not use the addresses.
PT0206(02/05)
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Preliminary Data Sheet
PT7C4307
Real-time Clock Module (I2C Bus)
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Maximum Ratings
Storage Temperature...................................................................................................................-65oCto +150oC
Ambient Temperature with Power Applied.........................................................................-40oCto +85oC
Supply Voltage to Ground Potential (Vcc to GND) ........................................................-0.3V to +6.5V
DC Input (All Other Inputs except Vcc & GND).............................................................-0.3V to (Vcc+0.3V)
DC Output Voltage (SDA, /INTA, /INTB pins).................................................................-0.3V to +6.5V
DC Output Current (FOUT).....................................................................................................-0.3V to (Vcc+0.3V)
Power Dissipation.........................................................................................................................320mW (depend on package)
Note:
Stresses greater than those listed under MAXIMUM RATINGS may cause permanent damage to the device. This is a stress rating only and
functional operation of the device at these or any other conditions above those indicated in the operational sections of this specification is not
implied. Exposure to absolute maximum rating conditions for extended periods may affect reliability.
Recommended Operating Conditions
Part No.
PT7C4307
Symbol
Description
Min
Type
Max
5
5.5
VCC
Power voltage
4.5
VBAT
Battery voltage
2
3.5
VIH
Input high level
2.2
VCC+0.3
VIL
Input low level
-0.3
0.8
TA
Operating temperature
-40
85
PT0206(02/05)
Unit
V
ºC
Ver: 0
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Preliminary Data Sheet
PT7C4307
Real-time Clock Module (I2C Bus)
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DC Electrical Characteristics
Unless otherwise specified, VDD = 4.5 ~ 5.5 V, TA = -40 °C to +85 °C
Sym.
Item
VCC Supply voltage
VBAT Supply voltage
VPF
Pin
Condition
VCC
VBATT
Power fail voltage
Note 4
ICC Current consumption
VCC
IBAT Current consumption
VBAT
VIL
VIH
VOL
IIL
Low-level input voltage
High-level input voltage
Low-level output voltage
Input leakage current
SCL
SCL
SDA
SCL
IOZ
Output current when OFF
SDA
OSC on, Note 3
OSC off, Note 1
OSC on, SQW/OUT off, Note 2
OSC on, SQW/OUT on (32kHz)
IOL = 5mA
Min
Typ
Max
Unit
4.5
2.0
5.0
5.5
3.5
V
1.216× 1.25× 1.284×
VBAT VBAT VBAT
1.5
200
300
500
480
800
0.8
2.0
0.4
1
1
V
mA
µA
nA
V
V
µA
µA
Note:
1. VCC = 5.0V and SDA, SCL = 5.0V.
2. VCC = 0V, VBAT = 3V.
3. SCL clocking at max frequency = 100kHz. SDA pin open, /EOSC bit = 0 (oscillator enabled)
4. VPF measured at VBAT = 3.0V.
PT0206(02/05)
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Preliminary Data Sheet
PT7C4307
Real-time Clock Module (I2C Bus)
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AC Electrical Characteristics
Sym
VHM
VHL
Description
Rising and falling threshold voltage high
Rising and falling threshold voltage low
Value
0.8 VCC
0.2 VCC
Unit
V
V
Signal
VHM
VLM
tr
tf
Over the operating range
Symbol
Item
Min.
Typ.
Max.
Unit
400
kHz
fSCL
tSU;STA
SCL clock frequency
START condition set-up time
0.6
µs
tHD;STA
START condition hold time
0.6
tSU;DAT
tHD;DAT1
tHD;DAT2
Data set-up time (RTC read/write)
Data hold time (RTC write)
Data hold time (RTC read)
200
35
0
µs
ns
ns
tSU;STO
STOP condition setup time
0.6
µs
tBUF
Bus idle time between a START and STOP condition
1.3
µs
tLOW
When SCL = "L"
1.3
µs
tHIGH
When SCL = "H"
0.6
tr
Rise time for SCL and SDA
0.3
µs
tf
Fall time for SCL and SDA
0.3
tSP*
CB
Allowable spike time on bus
Capacitance load for each bus line
50
400
µs
ns
pF
µs
µs
* Note: only reference for design
S
SCL
Sr
tLOW
fSCL
tHIGH
P
tHD;STA
tSP
tSU;STA
tBUF
SDA
tHD;STA
S
Start condition
Sr
Restart condition
tSU;DAT
tHD;DAT
P
tSU;STA
tSU;STO
tHD;STA
Stop condition
PT0206(02/05)
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Preliminary Data Sheet
PT7C4307
Real-time Clock Module (I2C Bus)
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Mechanical Information
DIP-8
X.XX
X.XX
DENOTES DIMENSIONS
IN MILLIMETERS
Note:
1) Controlling dimensions in inches.
2) Ref: JDDEC MS-001 BA
PT0206(02/05)
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Preliminary Data Sheet
PT7C4307
Real-time Clock Module (I2C Bus)
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SOIC-8
X.XX
X.XX
DENOTES DIMENSIONS
IN MILLIMETERS
Note:
1) Controlling dimensions in millimeters.
2) Ref: JDDEC MS-012 AA
PT0206(02/05)
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Preliminary Data Sheet
PT7C4307
Real-time Clock Module (I2C Bus)
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Notes
Pericom Technology Inc.
Email: [email protected] Site: www.pti.com.cn, www.pti-ic.com
China:
No. 20 Building, 3/F, 481 Guiping Road, Shanghai, 200233, China
Tel: (86)-21-6485 0576 Fax: (86)-21-6485 2181
Asia Pacific:
Unit 1517, 15/F, Chevalier Commercial Centre, 8 Wang Hoi Rd, Kowloon Bay, Hongkong
Tel: (852)-2243 3660
Fax: (852)- 2243 3667
U.S.A.:
3545 North First Street, San Jose, California 95134, USA
Tel: (1)-408-435 0800
Fax: (1)-408-435 1100
Pericom Technology Incorporation reserves the right to make changes to its products or specifications at any time, without notice, in order to improve design or
performance and to supply the best possible product. Pericom Technology does not assume any responsibility for use of any circuitry described other than the
circuitry embodied in Pericom Technology product. The company makes no representations that circuitry described herein is free from patent infringement or other
rights, of Pericom Technology Incorporation.
PT0206(02/05)
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