The bq4850Y RTC Module is a nonvolatile 4,194,304-bit SRAM organized as 524,288 words by 8 bits with an integral accessible real-time clock.

The device combines an internal lithium battery, quartz crystal, clock and power-fail chip, and a full CMOS SRAM in a plastic 32-pin DIP module. The RTC Module directly replaces industry-standard SRAMs and also fits into many EPROM and EEPROM sockets without any requirement for special write timing or limitations on the number of write cycles.

Registers for the real-time clock, alarm and other special functions are located in registers 7FFF8h–7FFFFh of the memory array.

The clock and alarm registers are dual-port read/write SRAM locations that are updated once per second by a clock control circuit from the internal clock counters.