I have a simple project to read the temperature and send it to a camera to display in the image. All works from a technical point of view, but the temperature seems 10F degrees too high, like 80F when it's 70F.
I measure the voltage at the tmp36 sensor and it's reading about 3/4 V and when I do a getVoltage(0) it reads .76 to .77. I've tried different formulas and come to the same conclusion, .765 or about 80F using commonly available formulas.
What I've tried so far:
- 2 different sensors from 2 different suppliers, both read the same
- bread boarding vs. solder, both read the same
- 5V and 3.3V on the board, the board voltage is correct, but results from the center pin are the same .76 to .77
- 0.1uF Cap between ground and volts, same results
- 0.01iF Cap between center pin and ground, same results
- putting sensor in ice water - lowered temp to 44F
- putting sensor between fingers - raised temp to about 90F
I plugged it in outside sending temps via WiFi, same results.