Name: 15x7 CharliePlex LED Matrix FeatherWing - Cool White
Brand: Adafruit
SKU: 3138

Logical pinout · physical placement not verified

3Vsecond from left
3.3V Feather power and logic rail used by the LED matrix; Adafruit Learn states the matrix uses the 3V pin for power and logic and typical current is about 40 mA depending on LEDs lit.
Type · PowerVoltage · 3.3V
GNDfourth from left
Ground return for the LED matrix; Adafruit Learn states the matrix uses the GND pin for power and logic.
Type · GroundVoltage · 0V
SCLto the left of SDA
I2C clock for IS31FL3731 LED matrix control; Adafruit Learn states all LED control is over I2C and SCL must be connected.
Type · I2C
SDArightmost
I2C data for IS31FL3731 LED matrix control; Adafruit Learn states all LED control is over I2C and SDA must be connected. Default I2C address is 0x74, configurable to 0x77 by solder jumper.
Type · I2C

Pin	Position	Type	Function	Voltage
3V	second from left	Power	3.3V Feather power and logic rail used by the LED matrix; Adafruit Learn states the matrix uses the 3V pin for power and logic and typical current is about 40 mA depending on LEDs lit.	3.3V
GND	fourth from left	Ground	Ground return for the LED matrix; Adafruit Learn states the matrix uses the GND pin for power and logic.	0V
SCL	to the left of SDA	I2C	I2C clock for IS31FL3731 LED matrix control; Adafruit Learn states all LED control is over I2C and SCL must be connected.
SDA	rightmost	I2C	I2C data for IS31FL3731 LED matrix control; Adafruit Learn states all LED control is over I2C and SDA must be connected. Default I2C address is 0x74, configurable to 0x77 by solder jumper.

Logical pinout · physical placement not verified

Pin details

4 connections

3V
3.3V Feather power and logic rail used by the LED matrix; Adafruit Learn states the matrix uses the 3V pin for power and logic and typical current is about 40 mA depending on LEDs lit.
PowerVoltage · 3.3V
second from left
GND
Ground return for the LED matrix; Adafruit Learn states the matrix uses the GND pin for power and logic.
GroundVoltage · 0V
fourth from left
SCL
I2C clock for IS31FL3731 LED matrix control; Adafruit Learn states all LED control is over I2C and SCL must be connected.
I2C
to the left of SDA
SDA
I2C data for IS31FL3731 LED matrix control; Adafruit Learn states all LED control is over I2C and SDA must be connected. Default I2C address is 0x74, configurable to 0x77 by solder jumper.
I2C
rightmost

Start wiring

Shield

Confirm the data interface matches your host board.

Module pins: 3V, GND, SCL, SDA. Schematik maps them to your board in the app.

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