BQ4822Y,pdf(RTC Module With 8K

The bq4822Y RTC Module is a non-volatile 65,536-bit SRAM organized as 8192 words by 8 bits with an integral real-time clock and CPU supervisor. The CPU supervisor provides a programmable watchdog timer and a microprocessor reset. Other features include an alarm, power-fail and periodic interrupt, and a battery low warning.

The device combines an internal lithium battery, quartz crystal, clock and power-fail chip, and a full CMOS SRAM in a plastic 28-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 1FF0h\x961FFFh of the memory array.