PCF8583
Clock and calendar with 240 x 8-bit RAM
Rev. 06 — 6 October 2010
Product data sheet
1. General description
The PCF8583 is a clock and calendar chip, based on a 2048 bit static CMOS
1
RAM
organized as 256 words by 8 bits. Addresses and data are transferred serially via the
two-line bidirectional I
2
C-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.
2. Features and benefits
I
2
C-bus interface operating supply voltage: 2.5 V to 6 V
Clock operating supply voltage 1.0 V to 6.0 V at 0
°C
to +70
°C
240
×
8-bit low-voltage RAM
Data retention voltage: 1.0 V to 6.0 V
Operating current (at f
SCL
= 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 (I
2
C-bus)
Automatic word address incrementing
Programmable alarm, timer, and interrupt function
Slave addresses: A1h or A3h for reading, A0h or A2h for writing
1.
The definition of the abbreviations and acronyms used in this data sheet can be found in