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→Testing the sensor
Temp: 14.71 °C, Voltage: 647 mV
Temp: 14.71 °C, Voltage: 647 mV
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== Improving the circuit ==
You may notice some variation in the temperature reading. This is due to the DC/DC regulation using running at lower frequency (to spare power when really few current required by the project). At lower frequency, the voltage regulation is less efficient and 3V3 rail will be more noisy.
As the TMP36 only requires 50µA and RP2040 consume very few current, you may encounter this situation.
The following scope capture show the 3V3 rail at very low current. As shown, je 3V3 contains lot of noise (Saw Waveform).
[[Fichier:Pico-3V3-regulation-at-low-current.png]]
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{{ENG-CANSAT-PICO-TRAILER}}