Click here to purchase one from the Adafruit shop
Click here to purchase one from the Adafruit shop
PCB files for the Adafruit PCF8523 RTC Breakout. Format is EagleCAD schematic and board layout
For more details, check out the product pages at
This is a great battery-backed real time clock (RTC) that allows your microcontroller project to keep track of time even if it is reprogrammed, or if the power is lost. Perfect for datalogging, clock-building, time stamping, timers and alarms, etc. Equipped with PCF8523 RTC - it can run from 3.3V or 5V power & logic!
Works great with an Arduino using our RTC library, with CircuitPython or with a Raspberry Pi (or similar single board linux computer)
- PCB & header are included
- Plugs into any breadboard, or you can use wires
- Two mounting holes
- Will keep time for 5 years or more
Note: This product does not come with a CR1220 coin cell battery. We recommend you purchase a coin cell battery to use with this product.
The PCF8523 is simple and inexpensive but not a high precision device. It may lose or gain up to 2 seconds a day. For a high-precision, temperature compensated alternative, please check out the DS3231 precision RTC. If you need a DS1307 for compatibility reasons, check out our DS1307 RTC breakout
Adafruit invests time and resources providing this open source design, please support Adafruit and open-source hardware by purchasing products from Adafruit!
Designed by Limor Fried/Ladyada for Adafruit Industries.
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