Electrical – Output Current of NodeMCU Digital Pin

#nodemcu

I'm trying to power the waterproof version of the DS18b20 Temperatur Sensor via the D1 (GPIO05) Pin.

I tested the setup first by using the 3.3 Volt Out Pin and by connecting a 4.7 Resistor between VCC and the Data Pin (GPIO04) and everything worked.

Now when I'm trying the same setup but with the D1 (GPIO05) Pin instead of the 3.3 V I only get the 85 °C Error reading as if it's not properly wired.

GPI05 puts out 3.3 V when set high so that should work. I also tried the setup with different sensors like the HR-SR04 Ultrasound and the DHT-22. They all work fine.

Best Answer

Espressif says that the ESP8266 (that's likely in your NodeMCU) can deliver 12mA per digital pin with a total of 72mA across all pins.

That answers your question but I don't think it'll solve your problem. The datasheet for the DS18b20 says it draws maybe 6mA tops so you should not be running into current limits.

Using your description I don't understand quite what your circuit looks like. Perhaps you could add a circuit diagram.

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