
U021 · M5Stack

Unit Light is a light intensity detection sensor. It integrates a photoresistor and a 10K adjustable resistor, capable of detecting light intensity and setting a light intensity threshold. The resistance of the photoresistor decreases as the incident light intensity increases, thus detecting the change in voltage, and obtaining light intensity data through AD conversion. To achieve more accurate light intensity measurements, this Unit also adopts the LM393 dual differential comparator, used… (M5Stack U021)
| Part number | U021 |
|---|---|
| Manufacturer | M5Stack |
| Category | Sensors › Light & Colour |
| Pins | 4 |
Light Sensor Unit with Photo-resistance 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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