This is an open-source USB real-time clock for the Raspberry Pi, allowing your project to maintain accurate time and alarm/alert functions without internet connectivity - regardless of power cycles and reboots. It uses a DS3231 RTC chip which runs the USB RTC with extremely high efficiency and accuracy. The RTC has cross-platform support which enables it to be used on different platforms such as Windows, MAC and more. The USB connectivity is handled via an MCP2221 which is a USB-to-UART/I2C serial converter. The battery holder accepts a CR1220 battery. Features * Temperature-compensated crystal oscillator * DS3231 advanced processor * MCP2221 USB-to-UART I2C serial converter * I2C/SMBus supported clock and data lines * Supports full-speed USB (12 Mb/s) * 64-byte Transmit * 64-byte Receive * USB 2.0 Compliant * Low-Power Consumption Resources * Product Wiki * GitHub Specifications * Battery Backup Input for continuous timekeeping * Operating temperature ranges: Commercial: 0°C to +70°C / Industrial: -40°C to +85°C * Low power consumption * Real-time clock counts seconds, minutes, hours, day, date, month and year (with leap year compensation valid up to 2100) * Two time-of-day alarms Package Contents * 1 x USB RTC Module Raspberry Pi & CR1220 battery not included https://elecena.pl/product/22724993/usb-real-time-clock-rtc-for-raspberry-pi-discontinued 2023-03-07 https://elecena.pl/product/22724993/usb-real-time-clock-rtc-for-raspberry-pi-discontinued 2024-09-19