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How can I acquire analog signals with Raspberry Pi?

Srin

Hello every one.

                         I have an idea which needs acquiring a analog signal and the processor board will be Raspberry Pi. Any ideas how it can be done? Any accessories or does it some external circuitry?

 

Please Advise.

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  • 0

    Have you done an analysis on the accuracy of your sensors that you want to hook up and the quantization error of your DAC ADC? You can always over-sample to get more resolution, but the accuracy will still be that same as for a single sample.

  • 0 in reply to michaelwylie

    but the accuracy will still be that same as for a single sample.

    That is not true. Under certain circumstances the accuracy improves with the square root of the number of samples. Take 4 samples together and you have one extra bit of accuracy. Take 100 samples, and you get a 10 fold improvement in accuracy.


    The "certain circumstances" are for example that there is a certain amount of noise in the ADC results. If the ADC is perfect and the signal at say 10.4, then taking 100 samples will always result in the ADC saying "10" and averaging that will give you the value "10", not hte 10.4 that we were expecting.

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  • 0 in reply to michaelwylie

    but the accuracy will still be that same as for a single sample.

    That is not true. Under certain circumstances the accuracy improves with the square root of the number of samples. Take 4 samples together and you have one extra bit of accuracy. Take 100 samples, and you get a 10 fold improvement in accuracy.


    The "certain circumstances" are for example that there is a certain amount of noise in the ADC results. If the ADC is perfect and the signal at say 10.4, then taking 100 samples will always result in the ADC saying "10" and averaging that will give you the value "10", not hte 10.4 that we were expecting.

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