This is a high-precision RTC expansion module specifically designed for the Raspberry Pi Pico.
The module incorporates a high-precision DS3231 RTC chip and uses the I2C bus for communication. The stackable design allows you to add other hardware whilst using the RTC board.
Note: Raspberry Pi Pico not included. You'll need a Pico with male headers soldered to it. You can grab a Pico here and Pico male headers here, or buy a Pico with pre-soldered headers.
Features
- Standard Raspberry Pi Pico header, supports Raspberry Pi Pico series
- Onboard high precision RTC chip DS3231, with backup battery holder
- Real-Time Clock Counts Seconds, Minutes, Hours, Date of the Month, Month, Day of the Week, and Year with Leap-Year Compensation Valid Up to 2100
- Optional format: 24-hour OR 12-hour with an AM/PM indicator
- 2x programable alarm clock
-
Online development resources and manual (Raspberry Pi Pico C/C++ and MicroPython examples)
- Dimensions: 52mm x 21mm
Note: Raspberry Pi Pico and CR1220 battery not included
What's On Board
-
1) DS3231
- High-precision RTC chip, I2C bus
-
2) RTC backup battery
- Supports CR1220 button cell
-
3) Power indicator
- Enabled by soldering a 0Ω resistor on the jumper, disabled by default
-
4) Raspberry Pi Pico header
- For attaching to Raspberry Pi Pico, stackable design
Resources
Package Contents
Raspberry Pi Pico and CR1220 battery not included
Pinout

Specifications
Operating Voltage |
3.3V |
Battery Backup Voltage |
2.3V ~ 5.5V |
Operating Temperature |
-40°C ~ +85°C |
Power Consumption |
100nA (sustains data and clock information) |