The Microchip Technology Inc 47C04 EERAM is a 4Kbit SRAM with EEPROM Backup. The I2C EERAM Memory is a Low-Cost NVSRAM that Eliminates the Need for an External Battery to Retain Data. The device is organized as 512 x 8 bits and utilizes the I2C serial interface. The 47C04 provides infinite read and write cycles to the SRAM while the EEPROM cells provide high endurance non-volatile storage of Data. With an external capacitor, SRAM data is automatically transferred to the EEPROM upon power-loss. Data can also be transferred manually by using either the hardware store pin or by software control.

4Kbit SRAM with EEPROM Back Up
Automatic Store to EEPROM upon power-down (using optional external capacitor)
Automatic Recall to SRAM Array upon power-up
Hardware Store Pin for manual Store Operations
Software commands for initiating Store and Recall Operations
Store Time 40ms (max)