The PD4992 is a CMOS integrated circuit which outputs 8-bit parallel time and calendar data in a system in which a microprocessor is employed. The PD4992 operates at 32.768 kHz and provides year, month, day of month, day of week, hour, minute, and second data to a system. The PD4992 internally contains a voltage regulator so that low power consumption operation and high accuracy are realized even if the supply voltage varies. The PD4992 uses the 8-bit bus to facilitate interfacing with a microprocessor.