bq4832Y

The bq4832Y RTC Module is a nonvolatile 262,144-bit SRAM organized as 32,768 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 alarm,power-fail, and periodic interrupts,andabattery-lowwarning.


The bq4832Y 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 numberofwritecycles.


Registers of bq4832Y for the real-time clock,alarm and other special functions are located in registers 7FF0h7FFFhofthememoryarray.


The clock and alarm registers of bq4832Y are dual-port read/write SRAM locations that are updated once per second by a clock control circuit from the internal clock counters. The dual-port registers allow clock updates to occur without interrupting normal access to the rest of the SRAMarray.


The bq4832Y also contains a powerfail-detect circuit. The circuit deselects the device whenever V_CC falls below tolerance,providing a high degree of data security. The battery is electrically isolated when shipped from the factory to provide maximum battery capacity. The battery remains disconnected until the first applicationofV_CC .