Real Time Clock Parallel 32KByte 32-Pin DIP Module

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, 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 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 7FF0h-7FFFh 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. The dual-port registers allow clock updates to occur without interrupting normal access to the rest of the SRAM array. The bq4832Y also contains a power-fail-detect circuit. The circuit deselects the device whenever VCC 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 application of VCC.

Integrated SRAM, real-time clock, CPU supervisor, crystal, power-fail circuit, and battery

Real-Time Clock counts hundredths of seconds through years in BCD format

RAM-like clock access

Compatible with industry-standard 32K x 8 SRAMs

Unlimited write cycles

10-year minimum data retention and clock operation in the absence of power

Automatic power-fail chip deselect and write-protection

Watchdog timer, power-on reset, alarm/periodic interrupt, power-fail and battery-low warning

Software clock calibration for greater than ±1 minute per month accuracy