i2c / SPI Character LCD Backpack - STEMMA QT / Qwiic
I2C/SPI backpack for HD44780-compatible character LCDs, reducing control to 2 pins (I2C) or 3 pins (SPI). Includes 5-pin terminal block for wiring and STEMMA QT/Qwiic connector. Compatible with Adafruit's character LCD library for Arduino and CircuitPython.
Pinout
- VIN
Power input for the I2C/SPI LCD backpack; Adafruit states it can be powered with 3 to 5V DC.
Type · powerVoltage · 3-5V DC - GND
Ground reference for backpack power and logic.
Type · groundVoltage · 0V - CLK / SCL / SCK
Clock line. In I2C mode this is SCL; after closing the SPI Enable jumper it is the SPI SCK clock input.
Type · signalVoltage · 3-5V logic level shifted - DAT / SDA / MOSI
Data line. In I2C mode this is SDA; after closing the SPI Enable jumper it is SPI MOSI, used to send data from the microcontroller to the backpack.
Type · signalVoltage · 3-5V logic level shifted - LAT
SPI latch input used when the backpack is configured for SPI by soldering the SPI Enable jumper.
Type · signal
Start wiring
SPI · I2C · 3.3 V · 3.3 – 5 V · Breakout
Adafruit describes product 398 as a 16x2 RGB backlight LCD using digital pins for LCD control and PWM pins for the backlight; the product…
Module pins: VIN, GND, CLK / SCL / SCK, DAT / SDA / MOSI, LAT. Schematik maps them to your board in the app.
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