ALS-PT19 RoHS-compliant ambient light sensor breakout with high IR rejection and a spectral response close to human vision; outputs an analogue voltage proportional to illuminance. Good drop-in upgrade from a CdS photocell.
Ground connection. Adafruit product page says to connect the - pad to ground.
Positive supply connection. Adafruit product page says to connect + to power.
Analogue output. Adafruit product page says to measure the analog voltage on the OUT pin and that voltage increases with more detected light.
| Pin | Position | Type | Function | Voltage |
|---|---|---|---|---|
| GND | ground | Ground connection. Adafruit product page says to connect the - pad to ground. | ||
| VCC | power | Positive supply connection. Adafruit product page says to connect + to power. | 2.5V to 5.5V or so, per Adafruit product page. | |
| OUT | signal | Analogue output. Adafruit product page says to measure the analog voltage on the OUT pin and that voltage increases with more detected light. | Analogue voltage output increases with detected light, per Adafruit product page. |
I2C · Analog · 3.3 – 5 V · Breakout
Adafruit describes the CdS photoresistor as a light sensor whose resistance falls as light increases, and its product page gives an examp…
Module pins: VCC, GND, OUT. Schematik maps them to your board in the app.
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