EERAM combines the reliability of an EEPROM with the performance of an SRAM. It is a nonvolatile SRAM with a shadow EEPROM backup.
I²C™ Serial EERAM Family
EERAM is a standalone SRAM memory with shadow EEPROM backup that helps retain the contents of the SRAM memory when system power is lost. The EERAM uses a small external capacitor to provide the energy needed to store the contents of the SRAM on to the EEPROM when system power is lost. Unlike NVSRAM, no external battery is needed. EERAM offers unlimited erase and write cycles to the memory and FRAM-like functionality at a fraction of the price.
The internal circuitry of the EERAM constantly monitors system power. Upon power-down or the inadvertent loss of system power below the trip voltage (VTRIP) the contents of the SRAM is securely transferred to the EEPROM array using energy stored in an external capacitor that is connected to the VCAP pin (pin 1). On power-up, the EERAM’s Auto-Store feature enables the contents of the EEPROM to be transferred back to the SRAM array when the system voltage goes back above VTRIP. The EERAM offers unlimited writes to the SRAM array and over 1M erase/write cycles to the EEPROM.