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.
Power input for the I2C/SPI LCD backpack; Adafruit states it can be powered with 3 to 5V DC.
Ground reference for backpack power and logic.
Clock line. In I2C mode this is SCL; after closing the SPI Enable jumper it is the SPI SCK clock input.
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.
SPI latch input used when the backpack is configured for SPI by soldering the SPI Enable jumper.
Back-side solder jumper that enables SPI control instead of the default I2C interface.
Sixteen output pins along the top of the board for attaching a character LCD; Adafruit states pin 1 is furthest left when viewing the front/logo side.
I2C address-selection jumpers used to chain up to 8 backpacks on the same I2C clock/data pins.
Back-side jumper between the CLK and 3-5V labels used for board voltage configuration per the Adafruit pinouts page.
| Pin | Position | Type | Function | Voltage |
|---|---|---|---|---|
| VIN | power | Power input for the I2C/SPI LCD backpack; Adafruit states it can be powered with 3 to 5V DC. | 3-5V DC | |
| GND | ground | Ground reference for backpack power and logic. | 0V | |
| CLK / SCL / SCK | signal | Clock line. In I2C mode this is SCL; after closing the SPI Enable jumper it is the SPI SCK clock input. | 3-5V logic level shifted | |
| DAT / SDA / MOSI | signal | 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. | 3-5V logic level shifted | |
| LAT | signal | SPI latch input used when the backpack is configured for SPI by soldering the SPI Enable jumper. | ||
| SPI Enable jumper | control | Back-side solder jumper that enables SPI control instead of the default I2C interface. | ||
| LCD connector pins 1-16 | connector | Sixteen output pins along the top of the board for attaching a character LCD; Adafruit states pin 1 is furthest left when viewing the front/logo side. | ||
| Address jumpers | control | I2C address-selection jumpers used to chain up to 8 backpacks on the same I2C clock/data pins. | ||
| 3-5V jumper | control | Back-side jumper between the CLK and 3-5V labels used for board voltage configuration per the Adafruit pinouts page. | 3-5V |
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.
16×2 and 20×4 character LCDs (parallel, I2C backpack, Qwiic, Grove), SPI TFTs from 0.71 to 3.5 inches, and large DSI and HDMI capacitive-touch panels up to 13.3 inches.
0.71" Round LCD Display Module - 160x160, SPI, 65K Colors visual preview0.71" Round LCD Display Module - 160x160, SPI, 65K Colors
0.71inch Double Eye Round LCD Display Module, 160×160 Resolution, SPI Interface, 65K Colors visual preview0.71inch Double Eye Round LCD Display Module, 160×160 Resolution, SPI Interface, 65K Colors
0.96" IPS LCD Display Module - 160x80, SPI visual preview0.96" IPS LCD Display Module - 160x80, SPI
1.28inch Round Touch LCD Module, 240×240, IPS, SPI/I2C visual preview1.28inch Round Touch LCD Module, 240×240, IPS, SPI/I2C
1.3" SPI Colour Square LCD (240x240) Breakout visual preview1.3" SPI Colour Square LCD (240x240) Breakout
1.3inch LCD Module, 240×240, IPS, SPI visual preview1.3inch LCD Module, 240×240, IPS, SPI
1.44inch LCD HAT for Raspberry Pi, 128×128, SPI visual preview1.44inch LCD HAT for Raspberry Pi, 128×128, SPI
1.54inch LCD Module, 240×240, IPS, 65K RGB, SPI visual preview1.54inch LCD Module, 240×240, IPS, 65K RGB, SPI
1.54inch Touch LCD Module, 240×240, IPS, SPI/I2C visual preview1.54inch Touch LCD Module, 240×240, IPS, SPI/I2C
1.5inch LCD Module, 240×280, IPS, Rounded, SPI visual preview1.5inch LCD Module, 240×280, IPS, Rounded, SPI
1.8" TFT LCD 160x128 RGB visual preview1.8" TFT LCD 160x128 RGB
Raw 1.8 inch 160x128 RGB TFT panel. SparkFun notes 9-bit SPI support, so treat it as a lower-level panel, not a drop-in for easier breakout boards.
1.83inch Touch LCD Module, 240×284, IPS, SPI/I2C visual preview1.83inch Touch LCD Module, 240×284, IPS, SPI/I2C
1.02" E-Ink Display Module - 128x80, Black/White, SPI visual preview
1.02" E-Ink Raw Display Panel - 128x80, Black/White, SPI visual preview
1.54inch e-Paper Module (B), 200×200, 3-Color, SPI visual preview
1.54inch e-Paper Module, 200×200, SPI visual previewWaveshare makes up the large majority of parts here and often sells the same panel twice: once as a raw display needing a separate driver board, and once as a module or HAT+ with the SPI controller attached.
Displays · E-paper displays · 102 parts
"Shake" 8x8 LED Matrix visual preview
10-Segment LED Bar Graph - Red visual preview
11x1 VFD Display Module visual preview
11x7 LED Matrix Breakout visual previewAdafruit HT16K33 backpacks, MAX7219 daisy-chains, NeoPixel and DotStar grids, HUB75 RGB matrix panels, charlieplexed arrays, bare clock displays, and two VFD character modules — almost 90 parts, none wired the same way.
Displays · LED displays · 88 parts
0.49inch OLED Display Module, 64×32, I2C visual preview
0.91" OLED Display Module - 128x32, I2C visual preview
0.96" OLED (B) - SPI/I2C visual preview
0.96" RGB OLED Display Module - 64x128, SPI, 65K Colors visual previewAbout 30 parts: monochrome I2C modules from 0.49 to 1.3 inches, SPI/I2C grayscale and 65K-color RGB panels up to 1.5 inches, a transparent OLED, and ecosystem-specific units for Raspberry Pi, FireBeetle and M5Stack Grove.
Displays · OLED displays · 29 parts
1.75mm PLA (1kg) - Black visual preview
1.75mm PLA (1kg) - Gold visual preview
1.75mm PLA (1kg) - Green visual preview
1.75mm PLA (1kg) - Natural visual previewDFRobot 1.75 mm PLA in 1 kg spools makes up the bulk of the group, in over 15 colors. Specialty options include PVA in both diameters, NinjaFlex flexible filament, Proto-Pasta conductive PLA, and wood-fill. OverLord printer spares and OverLord printers round out the hardware side.
Tools & prototyping · 3D printing · 53 parts