Product Material: Electronic materialSize: 38mm(length)*22mm(width)*14mm(height)Working voltage: 3.3--5.5VClock chip: high-precision clock chip DS3231Clock accuracy: within the range of 0-40, accuracy is 2ppm, and the annual error is about 1 minuteWith 2 calendar alarm clocksProgrammable square wave outputThe real-time clock generates seconds, minutes, hours, day of the week, date, month and year, and provides leap year compensation with a validity period up to 2100Built-in temperature sensor inside the chip, with an accuracy of 3Memory chip: AT24C32 (storage capacity 32K)IIC bus interface, the maximum transmission speed is 400KHz (when the working voltage is 5V)Other IIC devices can be cascaded, the 24C32 address can be modified by short-circuiting A0/A1/A2, the default address is 0x57With CR2032 batteryWiring instructions (take Arduino uno r3 as an example):SCLA5SDAA4VCC5VGNDGNDPacking method: single anti-static packagingQuantity: 3 piece setPackage content: 3*3 piece set of IIC module1.Real Time Clock ChipThe DS3231 AT24C32 is used as a real time clock chip which keeps the time running even if the main power supply is off (with the help of a battery).2.Complete Clock CalendarFunctionality Including Seconds, Minutes, Hours, Day, Date, Month, and Year, with Leap-Year Compensation Up to Year 2100.3.Extremely AccurateDS3231 memory chips - AT24C32 ,extremely accurate I2C real-time clock (RTC), with an integrated temperature-compensated crystal oscillator (TCXO) and crystal.4.Two programmProvides programmable time-of day alarms and a calendar can be set to a square wave output. Address and data are transferred serially through an I2C bidirectional bus.5.Safe EnoughA precision temperature-compensated voltage reference and comparator circuit monitors the status of VCC to detect power failures, provide a reset output. In addition, RST pin is monitored as generating a P reset.