Adafruit PCF8574 I2C GPIO Expander Breakout
STEMMA QT / Qwiic breakout for the PCF8574 I2C GPIO expander, adding eight quasi-bidirectional GPIO pins with configurable address jumpers and interrupt output.
Pinout
2 grouped source records are expanded into separate logical pads where unambiguous; physical placement is not implied.
- VINType · Power
- GNDType · Ground
- SCLType · I2C
- SDAType · I2C
- STEMMA QT connectorsType · I2C
- P7-P0Type · GPIO
- Expander +Type · Power
- Expander -Type · Ground
- A0 pinType · Unknown
- A0A1A2 jumpersType · Analog, Unknown
- INTType · Signal
- On LED jumperType · Unknown
| Pin | Type |
|---|---|
| VIN | Power |
| GND | Ground |
| SCL | I2C |
| SDA | I2C |
| STEMMA QT connectors | I2C |
| P7-P0 | GPIO |
| Expander + | Power |
| Expander - | Ground |
| A0 pin | Unknown |
| A0A1A2 jumpers | Analog, Unknown |
| INT | Signal |
| On LED jumper | Unknown |
2 grouped source records are expanded into separate logical pads where unambiguous; physical placement is not implied.
Pin details
12 connections- VINPower
- GNDGround
- SCLI2C
- SDAI2C
- STEMMA QT connectorsI2C
- P7-P0GPIO
- Expander +Power
- Expander -Ground
- A0 pinUnknown
- A0A1A2 jumpersAnalog, Unknown
- INTSignal
- On LED jumperUnknown
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