The bq4847 Real-Time Clock Module is a low-power microprocessor peripheral that integrates a time of-day clock, a100-year calendar, a CPU supervisor, a battery, and a crystal in a 28-pin DIP module. The part is ideal for fax machines, copiers, in dustrial control systems, point-of-sale terminals, data loggers, and computers.
Features
➤Real-Time Clock counts seconds through years in BCD format
➤Integrated battery and crystal
➤On-chip battery-backup switch over circuit with nonvolatile control for an external SRAM
➤130mAh battery capacity
➤±1 minute per month clock accuracy
➤Less than 500nA of clock operation current in backup mode
➤Microprocessor reset valid to VCC=VSS
➤Independent watchdog timer with a programmable time-out period
➤Power-fail interrupt warning
➤Programmable clock alarm interrupt active in battery-backup mode