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Analog temperature sensors TMP36 / LM35Dz

Hi all, I’m using copter 3.5.7, and was wondering if it is possible to connect an analog temperature sensor to the ADC 3.3V such as the TMP36 analog sensor, or the LM35Dz analog temperature sensor.

Thanks in advanced

@Josh_Agrably it is well possible to connect a TMP36 to any ADC, you’d have to set an individual offset and scalar after aliased data aquisition though. another issue might be HF-sensitivity of those sensors if used in proximity of HF transmitters (data radio, video transmission etc.). i subjectively have not succeeded to get reliable data from TMP36 type sensors in model aircraft applications, so i have been opting to use additional barometric sensors (BMP280 type) for external temperature measurements instead. they’re affordable, reliable and supported on ardupilot default firmware.

cheers, basti.

Thank you for your reply, can you explain how you set it up? I connected it to the ADC 3.3V. Did you set it up as a range finder? Or did you do something else?

RSSI analog input function perhaps?

i’d suggest an alias that has multiple instances and allows setting scalar and offset, like an arbitrary batt mon for example. i never got beyond ground testing though, tmp36 would go crazy as soon as i fired up my video transmitter…

Yes, scaling would be a problem using the RSSI parameters available.

while technically possible, using an analogue temp sensor imho requires workarounds and still comes with fundamental limitations regarding scaling, referencing, precision and integration. in contrast, an external baro provides direct digital temp readout, full logging, telemetry and OSD support with „pnp“ connectivity on default firmware at only marginal additional cost. that‘s why i opted for the baro approach.

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