
U144 · M5Stack

Unit Key is a single-key input unit with built-in RGB light. It uses a tactile mechanical blue switch with strong tactile feedback, and the keycap is replaceable, providing excellent mechanical feel and rebound. It features a built-in SK6812 programmable full-color RGB LED that supports 256 levels of brightness display. The unit exposes two digital IO interfaces for key state acquisition and light control. It is suitable for DIY projects requiring button input interaction. Features Blue… (M5Stack U144)
| Part number | U144 |
|---|---|
| Manufacturer | M5Stack |
| Category | User Input & Controls › Buttons & Keypads |
| Pins | 4 |
Mechanical Key Button Unit pinout
| Pin | Name | Type | Description |
|---|---|---|---|
| 1 | SIG1 | bidirectional | PORT.B: GPIO/analog; PORT.C: UART - see the unit's pin map |
| 2 | SIG2 | bidirectional | PORT.B: GPIO/analog; PORT.C: UART - see the unit's pin map |
| 3 | 5V | power | |
| 4 | GND | ground |
Schematic symbol and footprint
Schematic symbol
Footprint: Grove HY2.0 4-pin through-hole, 2.0 mm pitch — to scale, pad 1 in yellow (mm). Check against the datasheet before ordering PCBs.
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