The DS3231 High-Precision Real Time Clock Module is a low-cost, extremely accurate I2C real-time clock (RTC). It has an integrated temperature-compensated crystal oscillator (TCXO) and crystal. The device incorporates a battery input and maintains accurate timekeeping when the main power to the device is interrupted. Integrated crystal resonator improves the long-term accuracy of the device and reduces the number of components in the production line.

The DS3231 is available in commercial and industrial temperature ranges and is offered in a 16-pin, 300-mil SO package.

The RTC maintains seconds, minutes, hours, day, date, month, and year data. The date at the end of the month is automatically adjusted for months with fewer than 31 days, including corrections for leap year. The clock works in either the 24-hour or 12-hour format with an AM/PM indicator. Two programmable time-of-day alarms and a programmable square-wave output are provided. Addresses and data are transferred serially through an I2C bidirectional bus.

A precision temperature-compensated voltage reference and comparator circuit monitors the status of VCC to detect power failures, to provide reset output, and to automatically switch to the backup supply when necessary. Additionally, the RST pin is monitored as a pushbutton input for generating a uP reset.

This DS3231 High-Precision Real Time Clock Module dimension is 37mm x 22mm x 15mm.