DS3231 RTC module with AT24C32 memory for Arduino and microcontrollers. High precision I2C real time clock with battery backup, automatic leap year, two alarms, square-wave output. Replaces DS1307. 3.3V-5.5V operation, easy I2C interface, compact 38x22 mm. Ships from USA with free USPS Ground Advantage Shipping with Tracking. Battery not included.
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