The PCF8583 is a clockor calendar circuit based on a 2048-bit static CMOS 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 may be programmed as alarm registers or used as free RAM space. The remaining 240 bytes
I2C-bus interface operating supply voltage: 2.5 V to 6 V
Clock operating supply voltage (0 to +70 °C): 1.0 V to 6.0 V
240 ´ 8-bit low-voltage RAM· Data retention voltage: 1.0 V to 6 V
Operating current (at fSCL = 0 Hz): max. 50 mA
Clock function with four year calendar
Universal timer with alarm and overflow indication
24 or 12 hour format· 32.768 kHz or 50 Hz time base
Serial input/output bus (I2C)
Automatic word address incrementing
Programmable alarm, timer and interrupt function
Slave address:– READ: A1 or A3– WRITE: A0 or A2.
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