GENERAL DESCRIPTION
The PCA8581 and PCA8581C are low power CMOS EEPROMs with standard and wide operating voltages:

4.5 to 5.5 V (PCA8581)
2.5 to 6.0 V (PCA8581C).

In the following text, the generic term ‘PCA8581’ is used to refer to both types in all packages except when otherwise specified.
The PCA8581 is organized as 128 words of 8-bytes. Addresses and data are transferred serially via a two-line bidirectional bus (I2C-bus). The built-in word address register is incremented automatically after each written or read data byte. All bytes can be read in a single operation. Up to 8 bytes can be written in one operation, reducing the total write time per byte. Three address pins, A0, A1 and A2 are used to define the hardware address, allowing the use of up to 8 devices connected to the bus without additional hardware.

FEATURES
• Operating supply voltage:
   – 4.5 to 5.5 V (PCA8581)
   – 2.5 to 6.0 V (PCA8581C)
• Integrated voltage multiplier and timer for writing
   (no external components required)
• Automatic erase before write
• Low standby current; maximum 10 µA
• 8-byte page write mode
• Serial input/output bus (I2C-bus)
• Address by 3 hardware address pins
• Automatic word address incrementing
• Designed for minimum 10000 write cycles per byte
• 10 years minimum non-volatile data retention
• Infinite number of read cycles
• Pin and address compatibility to PCF8570C and PCF8582
• Operating ambient temperature: −25 to +85 °C.