PT7C4300 Datasheet, PDF (4/17 Pages) Pericom Semiconductor Corporation – Real-time Clock Module (I²c Bus)

Data Sheet
PT7C4300
Real-time Clock Module (I²C Bus)
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Function Description
Overview of Functions
1. 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 2100.
2. 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.
3. Oscillator enable/disable
Oscillator and time count chain can be enabled or disabled at the same time by ST bit.
4. Calibration function
With the calibration bits properly set, accuracy PT7C4300 can be improved to better than ±2 ppm at 25°C.
PT0222(02/06)
4
Ver: 0