DS3231MZ+

The DS3231M real-time clock can handle timekeeping when the main power is interrupted by utilizing a dual-supply configuration. This configuration allows the clock to operate on the VCC supply for normal system operation and switch to the VBAT supply for backup power in the absence of the primary system power . This ensures that the timekeeping circuits remain alive during power interruptions, maintaining accurate timekeeping functionality.

The typical operating circuit for the DS3231M real-time clock includes a battery input and maintains accurate timekeeping when the main power is interrupted. It incorporates a microelectromechanical systems (MEMS) resonator for enhanced long-term accuracy and reduced piece-part count in manufacturing. The DS3231M is available in the same footprint as the popular DS3231 RTC. .

The DS3231M real-time clock features a stable and accurate reference clock, maintaining accuracy within 0.432 seconds-per-day from -40°C to +85°C. It includes a low-power clock/calendar with two programmable time-of-day alarms and provides an interrupt signal or a 1Hz square wave. The clock/calendar displays seconds, minutes, hours, day, date, month, and year information, automatically adjusting for month end dates and leap years. It operates in both 24-hour and 12-hour formats with an AM/PM indicator. The internal registers are accessible through an I2C bus interface. Additionally, it has a precision temperature-compensated voltage reference and comparator circuit for monitoring VCC status, detecting power failures, providing a reset output, and switching to a backup supply when needed. The clock also has a pushbutton input for generating a microprocessor reset.