# Adafruit PCF8523 Real Time Clock Assembled Breakout Board

**Type:** Product page · **SKU:** ADA3295 · **Brand:** [Adafruit](https://core-electronics.com.au/brands/adafruit-australia)
**Page:** https://core-electronics.com.au/adafruit-pcf8523-real-time-clock-assembled-breakout-board.html ([markdown](https://core-electronics.com.au/adafruit-pcf8523-real-time-clock-assembled-breakout-board.html.md))

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...

## Pricing

- **Price:** $14.20 (inc GST) — $12.91 AUD, exc GST
- **Quantity discounts:** 10+ $12.52 (exc GST) · 50+ $12.26 (exc GST)

## Availability & dispatch

- Available with a lead time — expect dispatch between Aug 20 and Aug 24.

## Restrictions

Restrictions apply to this equipment as it uses button/coin cell batteries:

- The equipment is intended to be used in trades, professions or industries
- The equipment is not intended for sale to the general public
- The equipment is not intended to be used where children are present
- You are aware that this equipment may not meet child safety testing requirements as it is not intended to be used by consumers or general public, but rather, is intended to be used in trades, professions or industries in conjunction with the limitations and restrictions listed above
- You are aware that these restrictions are due to a change in [A](https://www.accc.gov.au/media-release/businesses-on-notice-as-mandatory-button-battery-laws-commence)[ustralian legislation in 2022](https://www.accc.gov.au/media-release/businesses-on-notice-as-mandatory-button-battery-laws-commence) for button/coin cell batteries
 
![Button Battery Warning](https://core-electronics.com.au/attachments/uploads/iec-button-battery.png)

A declaration of use will need to be submitted during checkout.

## Description

**Note: This product does not come with a CR1220 coin cell battery.[ We recommend one of these batteries if you're in need of a CR1220 for this RTC Module](https://core-electronics.com.au/coin-cell-battery-12-5mm-cr1220.html)**

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 data logging, 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 Adafruit's RTC library](https://github.com/adafruit/RTClib) or with a [Raspberry Pi (or similar single board Linux computer)](https://learn.adafruit.com/adding-a-real-time-clock-to-raspberry-pi)

- PCB & header are included
- Plugs into any breadboard or you can use wires
- Two mounting holes
- Will keep time for 5 years or more
 
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](https://core-electronics.com.au/adafruit-ds3231-precision-rtc-breakout.html). If you need a DS1307 for compatibility reasons, check out Adafruit's [DS1307 RTC breakout](https://core-electronics.com.au/adafruit-ds1307-real-time-clock-assembled-breakout-board.html)

## Technical Details

Dimensions:

- Length: 25.8mm/1.02in
- Width: 21.8mm/0.86in
- Height: 5mm/0.2in
- Weight: 2.3g/0.09oz
- Mounting holes are 2.2mm(0.086in) diameter, 25mm(0.98in) apart
- This board/chip uses I2C 7-bit address 0x68

## Images

- [Product image 1](https://core-electronics.com.au/media/catalog/product/3/2/3295-00.jpg)