
Catalog
SRAM Nonvolatile Controller IC for 4 SRAM Banks
Key Features
• Power monitoring and switching for 3-volt battery-backup applicationsWrite-protect control2-input decoder for control of up to 4 banks of SRAM3-volt primary cell inputsLess than 10ns chip-enable propagation delay5% or 10% supply operationPower monitoring and switching for 3-volt battery-backup applicationsWrite-protect control2-input decoder for control of up to 4 banks of SRAM3-volt primary cell inputsLess than 10ns chip-enable propagation delay5% or 10% supply operation
Description
AI
The CMOS bq2204A SRAM Non-volatile Controller Unit provides all necessary functions for converting up to four banks of standard CMOS SRAM into nonvolatile read/write memory.
A precision comparator monitors the 5V VCCinput for an out-of-tolerance condi-tion. When out-of-tolerance is detected, the four conditioned chip-enable outputs are forced inactive to write-protect up to four banks of SRAM.
During a power failure, the external SRAMs are switched from the VCCsupply to one of two 3V backup sup-plies. On a subsequent power-up, the SRAMs are write-protected until a power-valid condition exists.
During power-valid operation, a two-input decoder transparently selects one of up to four banks of SRAM.
The CMOS bq2204A SRAM Non-volatile Controller Unit provides all necessary functions for converting up to four banks of standard CMOS SRAM into nonvolatile read/write memory.
A precision comparator monitors the 5V VCCinput for an out-of-tolerance condi-tion. When out-of-tolerance is detected, the four conditioned chip-enable outputs are forced inactive to write-protect up to four banks of SRAM.
During a power failure, the external SRAMs are switched from the VCCsupply to one of two 3V backup sup-plies. On a subsequent power-up, the SRAMs are write-protected until a power-valid condition exists.
During power-valid operation, a two-input decoder transparently selects one of up to four banks of SRAM.