3.3V Single-Piece 1Mb Nonvolatile SRAM

The DS2045L is a 1Mb reflowable nonvolatile (NV) SRAM, which consists of a static RAM (SRAM), an NV controller, and an internal rechargeable manganese lithium (ML) battery. These components are encased in a surface-mount module with a 256-ball BGA footprint. Whenever V_CC is applied to the module, it recharges the ML battery, powers the SRAM from the external power source, and allows the contents of the SRAM to be modified. When V_CC is powered down or out-of-tolerance, the controller write-protects the SRAM's contents and powers the SRAM from the battery. The DS2045L also contains a power-supply monitor output, active-low RST, which can be used as a CPU supervisor for a microprocessor.