ET-D02
HT16K33 LED Matrix Driver
Drive 128 LEDs and scan 39 keys over I²C
AED 19.00
Out of stockOverview
Drive 128 LEDs and scan 39 keys over I²C
The ET-D02 is built around the Holtek HT16K33 — 128 LEDs (16 rows × 8 commons), 16-step dimming, 39-key matrix scan. It connects over I²C 0x70; Qwiic / STEMMA QT and is powered from 4.5–5.5V (3.3V works, dimmer).
Two Qwiic / STEMMA QT connectors let you chain it with other boards without soldering, and the 2.54 mm header fits a breadboard.
Designed in Dubai by ElectroTrical — the full schematic, BOM and design notes are published below.
Good for
- Custom LED matrices and bar graphs
- Front panels with keys
- Art and signage projects
Key features
What makes it different
Driver
Holtek HT16K33: 128 LEDs (16 rows × 8 commons), 16-step dimming, 39-key matrix scan
Interface
I²C 0x70; Qwiic / STEMMA QT
Supply
4.5–5.5V (3.3V works, dimmer)
Outputs
ROW0–15 (anodes) and COM0–7 (cathodes) on 2.54mm headers — wire your own matrix, bar graph or keypad
Qwiic / STEMMA QT
Two JST-SH connectors plus a 2.54 mm header — 3.3 V and 5 V hosts.
Open documentation
Schematic, BOM and layout notes published for every board.
Specifications
Technical specifications
| Driver | Holtek HT16K33: 128 LEDs (16 rows × 8 commons), 16-step dimming, 39-key matrix scan |
|---|---|
| Interface | I²C 0x70; Qwiic / STEMMA QT |
| Supply | 4.5–5.5V (3.3V works, dimmer) |
| Outputs | ROW0–15 (anodes) and COM0–7 (cathodes) on 2.54mm headers — wire your own matrix, bar graph or keypad |
| Size | 50.8 × 25.4 mm |
|---|---|
| Mounting | 4 × M2.5 holes, 2.54 mm from each corner |
| Connectors | 2 × Qwiic / STEMMA QT (JST SH 4-pin) · 4-pin 2.54 mm header |
| Main IC | HT16K33 (LCSC C87502) |
| Revision | Rev A |
| Libraries | Adafruit_LEDBackpack, adafruit-circuitpython-ht16k33 |
|---|
| JP1 (default Closed) | Power LED (cut = off) |
|---|---|
| JP2 (default Closed) | I²C pull-ups |
Performance
Capacity
Pinout
Pin map and connections
| Pin | Name | Type | Function |
|---|---|---|---|
| 1 | VIN | Power | 5V |
| 2 | GND | Ground | Ground |
| 3 | SCL | I²C | I²C clock |
| 4 | SDA | I²C | I²C data |
Qwiic / STEMMA QT pins: GND, VIN, SDA, SCL (same on both connectors). I²C pull-ups (10 kΩ) are on the board; cut JP2 to remove them.
Mechanical
Dimensions and what's in the box
In the box
- 1 × ET-D02 HT16K33 LED Matrix Driver (assembled)
- 1 × 4-pin 2.54 mm male header, unsoldered
Getting started
- Plug in a Qwiic / STEMMA QT cable, or solder the header and wire VIN, GND, SDA and SCL
- Libraries: Adafruit_LEDBackpack, adafruit-circuitpython-ht16k33
- Run an I²C scanner to confirm the address: 0x70
Compare
Which segment display?
| HT16K33 LED Matrix Driver (this board)This board | ET-D01 HT16K33 4-Digit 7-Segment Display | ET-D03 MAX7219 8-Digit Display | ET-D04 TM1637 4-Digit Display | |
|---|---|---|---|---|
| What it does | Drive 128 LEDs and scan 39 keys over I²C | 0.56" red 4-digit display on I²C, Qwiic | Eight 7-segment digits on SPI, daisy-chainable | Large 0.56" 4-digit display on two GPIO pins |
| Interface | I²C 0x70; Qwiic / STEMMA QT | I²C 0x70; Qwiic / STEMMA QT | SPI (DIN, CS, CLK) with DOUT for daisy-chaining… | CLK + DIO on any two GPIOs |
| Best for | Custom LED matrices and bar graphs | Clocks and timers | Frequency and voltage meters | Simple clocks |
| Price | 19 AED | 39 AED | 11 AED | 9 AED |
Downloads
Documents and design files
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