Modular power supply -PCF8563 PCF8563T 8563 IIC RTC Real Time Clock Module For Arduino Highlights generic brand PCF8563 PCF8563T 8563 IIC RTC Real Time Clock Module For Arduino Real time clock module based on the NXP PCF8563T , a programmable high precision real-time clock chipset communicating at up to 400 kHz/400 KB/S. It offers several functions such as external programmable clock output, alarm, timer, it has a external quartz and a backup battery. More stable and accurate than DS1302 or DS1307 Description: The PCF8563 RTC board provides the real-time clock/calendar function, which can be powered by on-board battery and works independently even when the MCU is powered off. Cost-effective and highly accurate I2C real-time clock (RTC) More stable and accurate than DS1302 or DS1307 I2C bus support (by pin, row seat docking method, which can use multiple I2C modules) Wide voltage range: 1.0-5.5V Typical value: 0.25uA Output frequency: 32.768KHz, 1024Hz, 32Hz, 1Hz 4 kinds of real-time clock/calendar functions Package includes: 1x PCF8563 RTC card 1x 3.3V button battery 1x Pin Header