Did someone tried to connect a 5 volt analog sensor to an analog port which works on 0-3,3 volt ?
I think I can use this:
If I use R1= 5k6 and R2= 10k, then the maximum Vout (when Vin=5V) =3,205 volt, so this looks safe for the Netduino.
Can I use this, or should I use resisors with a higher value ?
You should be good so long as you keep the analog channels down to 3.3V maximum.
The digital channels are 5V tolerant but you need to be careful with the analog pins when used for analog readings.
I’m going to be looking a sensor which has a similar output range, mine is 0->4.5V so I will be looking at a similar solution.
By the way, the Electronics Tutorial has a great section on DC Circuit Basics which covers voltage division very thoroughly and even includes two labs that use it. In particular, there is a lab that does 5V to 3.3V.
I highly recommend reading the whole chapter.