HT16K33 Segment Display Family
HT16K33-based LED segment displays including 14-segment alphanumeric, 7-segment numeric, and LED matrix backpacks. Bright, readable from a distance.
Say it to PAL
“Show a word on the display.”
The code PAL writes
p.write('qwiic-alphanumeric', 'text', { text: 'COOL' });
p.log('Segment display updated');
await p.waitUntilStopped();“Show the temperature on the display.”
The code PAL writes
p.onSensorChange('qwiic-tmp117', 'temperature', (val) => {
p.write('qwiic-alphanumeric', 'text', { text: val.toFixed(1) });
});
await p.waitUntilStopped();When to pick it
Best when you need readable text or numbers visible from a distance — bright LED segments are easier to read across a room than OLED pixels.
Good to know
- Limited character set — letters, numbers, and basic symbols only. No graphics or custom icons.
- Only 4 characters per board — plan messages accordingly or chain multiple displays.
About it
The HT16K33 is Holtek's versatile LED controller IC, used across Adafruit's backpack product line and SparkFun's Qwiic alphanumeric displays. Drives 14-segment alphanumeric digits, 7-segment numeric digits, and 8x8 LED matrices. Very bright and readable from across a room. I2C addressable (0x70-0x77) so up to 8 displays can be chained on a single bus. Available in multiple colors and form factors.
Where to buy
Facts
Tested
It is in our catalog, but nobody has checked it on a real board. It may not work yet. Its driver is written, but it has not been tested on hardware yet.
I2C address
0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77
The HT16K33 Segment Display Family answers at I2C address 0x70. A jumper or pin moves it to 0x71 or 0x72 or 0x73 or 0x74 or 0x75 or 0x76 or 0x77.
Current
40 mA
The catalog lists a typical draw of 40 mA for the Alphanumeric LED, copied from the maker’s description and not measured by Palpable.
Board size
50.8 × 27.94 mm
The Alphanumeric LED board measures 50.8 × 27.94 mm and stands 8.6 mm tall with its parts. It has 4 mounting holes. These dimensions are from the maker’s mechanical drawing.
Free to reuse
Every fact here is open data under CC BY 4.0. Copy it into your own docs or code, and credit Palpable. Download it
This record was last changed on October 9, 2026.