RTC Module With 512Kx8 NVSRAM, Watchdog Timer, UP Reset, Interrupts And Battery Low Warning
The BQ4852Y 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 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 36-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 7FFF0h7FFFFh 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 BQ4852Y 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.
By Texas Instruments
|BQ4852YMC-85||Texas Instruments||0 TIMER(S), REAL TIME CLOCK, PDIP36|
|BQ4852Y Pb-Free||BQ4852Y Cross Reference||BQ4852Y Schematic||BQ4852Y Distributor|
|BQ4852Y Application Notes||BQ4852Y RoHS||BQ4852Y Circuits||BQ4852Y footprint|