vitzmuni:
Wawa, I don't have a capcitor , i doubt a smoothing capacitor will help when the ADC output is so high... but i'll give it a shot . it will take time for me to get a capacitor.My project is a autonomous robot (4WD) which detects fire and extinguishes it. It's also supposed to take the temperature into considerations and alert in case of high temperatures.
I've considered purchasing a digital (DHT11 or DHT22) sensor, but the fact this sensor comes with a header file with ready functions will not be appreciated by the proffessors. It's much easier to deal with analog sensor (as i have plenty of work with other sensors ahead of me).
A bypass capacitor has nothing to do with the A/D.
It's wise to use a cap across the POWER pins of the temp sensor if the wires are long.
You will find that it's much harder to make an analogue sensor stable in a bigger project.
Stable temps depends on two things.
- Sensor output voltage.
- Reference voltage of the A/D.
That's why I suggested using the internal 1.1volt Aref instead of the potentially unstable default Aref (VCC).
Ground current is another problem. The LM35 must have it's own ground wire to the Arduino (not shared).
Leo..