Real-time clock (RTC) with automatic switchover to backup supply

The BQ32002 device is a compatible replacement for industry standard real-time clocks.

The BQ32002 features an automatic backup supply that can be implemented using a capacitor or non-rechargeable battery. The BQ32002 has a programmable calibration adjustment from –63 ppm to +126 ppm. The BQ32002 registers include an OF (oscillator fail) flag indicating the status of the RTC oscillator, as well as a STOP bit that allows the host processor to disable the oscillator. The time registers are normally updated once per second, and all the registers are updated at the same time to prevent a timekeeping glitch. The BQ32002 includes automatic leap-year compensation.