ITEM NAME:DC 3.3-5.5V DS3231 High Precision Real-Time Clock Module for MCU Y9Z2 DC 3.3-5.5V DS3231 High Precision Real-Time Clock Module for MCU Y9Z2 Product Name : Real Time Clock Module;Chip : DS3231 Voltage : DC 3.3-5.5V;Pin Number : 6.Clock chip: High-precision clock chip DS3231;. With two calendar alarm clock;. Clock Accuracy: 0~40 range, the accuracy 2ppm, the error is about 1 minute;. With output TTL level signal indication;. The standard 2.54mm pin to do input and output connections;.