ADC audio sampling circuit

[sv2agw]

Posted on May 13, 2015 at 16:36

Hi

I connected audio to ADC and can DSP with success only if the audio is from speaker out. I need to connect audio from a device which outputs 500mvpp. I am using the follow input circuit

http://www.frinos.com/adc.png

Thank you in advance for any help

Georges

[raptorhal2]

Posted on May 13, 2015 at 17:52

500 mv will give a swing of 1/6 the ADCs range of 4095 counts. But the capacitor, 2 resistors and the ADC input resistance and capacitance form a network that will change that. Put a 'scope on the ADC input signal to see if it is as expected.

Cheers, Hal