Name: LED Charlieplexed Matrix - 9x16 LEDs - Blue
Brand: Adafruit
SKU: 2973

Logical pinout · physical placement not verified

VCC
Power input for the IS31FL3731/LED matrix board; Adafruit Learn states the IS31 can be powered from 2.7-5.5 VDC and this voltage is also used for logic.
Type · PowerVoltage · 2.7-5.5V DC, same voltage used for power and logic per Adafruit Learn pinouts
GND
Ground reference for power and I2C logic.
Type · GroundVoltage · 0V
SDA
I2C data line; connect to the microcontroller I2C SDA pin. Learn page states built-in 20K pullups to VCC.
Type · I2CVoltage · logic level follows VCC
SCL
I2C clock line; connect to the microcontroller I2C SCL pin. Learn page states up to 400KHz clock speed and built-in 20K pullups to VCC.
Type · I2CVoltage · logic level follows VCC
ADDRI2C address jumper
I2C address selection jumper/pin; Adafruit Learn states the board can be chained by soldering address jumpers closed to select alternate I2C addresses.
Type · Control
SDBshutdown
Shutdown pin; Adafruit Learn states it is pulled up to VCC by default and can be connected to ground to put the chip in shutdown mode.
Type · ControlVoltage · pulled up to VCC by default; ground to shut down

Pin	Type	Function	Voltage
VCC	Power	Power input for the IS31FL3731/LED matrix board; Adafruit Learn states the IS31 can be powered from 2.7-5.5 VDC and this voltage is also used for logic.	2.7-5.5V DC, same voltage used for power and logic per Adafruit Learn pinouts
GND	Ground	Ground reference for power and I2C logic.	0V
SDA	I2C	I2C data line; connect to the microcontroller I2C SDA pin. Learn page states built-in 20K pullups to VCC.	logic level follows VCC
SCL	I2C	I2C clock line; connect to the microcontroller I2C SCL pin. Learn page states up to 400KHz clock speed and built-in 20K pullups to VCC.	logic level follows VCC
ADDRI2C address jumper	Control	I2C address selection jumper/pin; Adafruit Learn states the board can be chained by soldering address jumpers closed to select alternate I2C addresses.
SDBshutdown	Control	Shutdown pin; Adafruit Learn states it is pulled up to VCC by default and can be connected to ground to put the chip in shutdown mode.	pulled up to VCC by default; ground to shut down

Logical pinout · physical placement not verified

Pin details

6 connections

VCC
Power input for the IS31FL3731/LED matrix board; Adafruit Learn states the IS31 can be powered from 2.7-5.5 VDC and this voltage is also used for logic.
PowerVoltage · 2.7-5.5V DC, same voltage used for power and logic per Adafruit Learn pinouts
GND
Ground reference for power and I2C logic.
GroundVoltage · 0V
SDA
I2C data line; connect to the microcontroller I2C SDA pin. Learn page states built-in 20K pullups to VCC.
I2CVoltage · logic level follows VCC
SCL
I2C clock line; connect to the microcontroller I2C SCL pin. Learn page states up to 400KHz clock speed and built-in 20K pullups to VCC.
I2CVoltage · logic level follows VCC
ADDRI2C address jumper
I2C address selection jumper/pin; Adafruit Learn states the board can be chained by soldering address jumpers closed to select alternate I2C addresses.
Control
SDBshutdown
Shutdown pin; Adafruit Learn states it is pulled up to VCC by default and can be connected to ground to put the chip in shutdown mode.
ControlVoltage · pulled up to VCC by default; ground to shut down

Start wiring

I2C · SPI · Single data line · 5 V · 3.3 – 5 V · Bare

Confirm the data interface matches your host board.

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

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