DS3231 RTC Real Time Clock Module 3.3V/5V with Battery

A compact, high-accuracy real-time clock module built around the DS3231 chip, which has a temperature-compensated crystal oscillator (TCXO) inside. It keeps accurate time and date for Arduino, ESP32, STM32 and Raspberry Pi projects. An onboard rechargeable backup cell keeps the clock running when main power is off.

It works on both 3.3V and 5V, and its 5-pin female header plugs straight onto the Raspberry Pi GPIO header, so no wiring or level shifter is needed.

Features

• DS3231 RTC with built-in temperature-compensated crystal (about ±2 ppm from 0–40°C)
• Tracks seconds, minutes, hours, day, date, month and year, with leap-year correction up to 2100
• Two programmable time-of-day alarms
• Square-wave output (1 Hz) and 32.768 kHz output
• Onboard digital temperature sensor
• Soldered rechargeable coin cell, recharged from the board supply, keeps time during power loss
• 5-pin female header (+, D, C, NC, −) that sits directly on Raspberry Pi pins 1–9
• Fast-mode I2C interface (400 kHz)

Specifications

• Chip: DS3231
• Supply voltage: 2.3V – 5.5V (3.3V and 5V compatible)
• Interface: I2C (address 0x68)
• Connector: 5-pin female header
• Operating temperature: -40°C to +85°C
• Backup: rechargeable coin cell (soldered, included)

Applications

• Data loggers and timestamped sensor readings
• Digital clocks, timers and alarms
• Scheduled automation and home-automation controllers
• Adding a hardware clock to a Raspberry Pi with no network

Package includes

• 1 × DS3231 RTC Module with battery