General description

The PCF8583 is a clock and calendar chip, based on a 2048 bit static CMOS1 RAM organized as 256 words by 8 bits. Addresses and data are transferred serially via the two-line bidirectional I2C-bus. The built-in word address register is incremented automatically after each written or read data byte. Address pin A0 is used for programming the hardware address, allowing the connection of two devices to the bus without additional hardware.

The built-in 32.768 kHz oscillator circuit and the first 8 bytes of the RAM are used for the clock, calendar, and counter functions. The next 8 bytes can be programmed as alarm registers or used as free RAM space. The remaining 240 bytes are free RAM locations.

Features and benefits

I2C-bus interface operating supply voltage: 2.5 V to 6 V

Clock operating supply voltage 1.0 V to 6.0 V at 0°Cto+70°C

240×8-bit low-voltage RAM

Data retention voltage: 1.0 V to 6.0 V

Operating current (at fSCL= 0 Hz): max 50 μA

Clock function with four year calendar

Universal timer with alarm and overflow indication

24 hour or 12 hour format

32.768 kHz or 50 Hz time base

Serial input and output bus (I2C-bus)

Automatic word address incrementing

Programmable alarm, timer, and interrupt function

Slave addresses: A1h or A3h for reading, A0h or A2h for writing