interface an +-10V analog signal to the ADC

[mystery]

I want to interface an +-10V analog signal to the ADC of the microcontroller.
I need to convert the incoming signal to the 0-3.3V interval.

Is there any schematic or application note for this?

thanks

 

[opterix]

Be recursive, you could use and amp-op to reduce the amplitude of the signal, and then mount it on a DC signal. Its not a elegant solution but it should work.

 

[IanP]

Very similar problem was discussed here some time ago ..

Take a look at: example.png
In your case:
Vr-->0v
Vref-->3.3V
All you need to do is to calculate values of R1, R2 and R3 ..
(you may need to include the input impedance of the ADC)

Regards,
IanP

 

[angelote]

Look at ADS1251's pdf from TI.

There is a schematic for a voltage range converter. You can analyse and adapt it for your needs.