Adafruit PCF8523 Real Time Clock Assembled Breakout Board

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.

VCC
Power pin for the PCF8523 breakout. Adafruit Learn says to power it at the microcontroller logic level.
Type · powerVoltage · 3-5VDC input, same as logic level
GND
Common ground for power and logic.
Type · groundVoltage · 0V
SCL
I2C clock line.
Type · signalVoltage · logic level follows VCC
SDA
I2C data line.
Type · signalVoltage · logic level follows VCC
STEMMA QT
STEMMA QT connector on the STEMMA QT version for I2C/power chaining.
Type · connectorVoltage · carries VCC, GND, SCL, and SDA
SQW

Start wiring

I2C · 3-5VDC input, same as logic level · 0V

Confirm the data interface matches your host board.

Module pins: VCC, GND, SCL, SDA, SQW. Schematik maps them to your board in the app.

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