The DS2030W is a 256kb 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 VCC 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 VCC is powered down or out of tolerance, the controller write-protects the SRAM's contents and powers the SRAM from the battery. The DS2030W also contains a power-supply monitor output, RST, which can be used as a CPU supervisor for a microprocessor.