Timekeeping and system supervision in one package
The DS1501WZN+T&R from Analog Devices is a parallel-interface real-time clock (RTC) that combines timekeeping with a 256-byte NVSRAM, alarm, watchdog timer, and square-wave output — a single-chip solution for embedded systems that need to track calendar time and supervise processor activity. It formats time as HH:MM:SS in 24-hour mode and date as YY-MM-DD-dd, with leap-year correction through 2099 and Y2K compliance built in.
Supply rails and power budget for the BOM
The main supply range is 3 V to 3.6 V, with a separate battery-backup input accepting 2.5 V to 3.7 V — the RTC maintains timekeeping and NVSRAM retention when the main rail drops. Timekeeping current draw is 4 mA maximum across the full supply range, which sets the battery-life floor in backup mode.