How can I analyze Squre wave with AD9236

I want to getting a voltage level from AD9236. But when I test AD9236 (ADC) It is difficult to anlayze a signal with low frequency. As this reason, I can't get a DC(direct current) voltage value.

ADC is always used for fluctuating signal?

As far as I know, ADC is convert analog level to digital data.

(Left one is squre wave sampled result. The other is sine wave sampled result)

squre wave, sine wave source is wave generator.

Below picture is the oscilloscope from generator. I think generator is not wrong.

 

  • 0
    •  Analog Employees 
    on Mar 24, 2017 7:53 PM

    Hello,

    It would appear that you are using the AC transformer coupled path with a low frequency square or sine wave that falls below the cut-off frequency.

    Perhaps you can inject a higher frequency sine or square wave at 1+ MHz.  Other option is to reconfigure the evaluation board for the amplifier path and DC couple the input into the ADC.  This method would allow you to observe low frequency signals down to DC.

    Regards.

  • Yes... My Board circuit is configured with single ended... this includes capacitor..it is reason that I can not analyze low-frequency.. Thank you so much. I will learn more 

  • 0
    •  Analog Employees 
    on Apr 3, 2017 9:14 PM

    OK.  Hopefully you can get square wave display if frequency of square wave (or capacitor size) is increased so that the fundamental tone of square wave (i.e. frequency of oscillation) is above the lower cut-off frequency set by the capacitor and input resistance to the AD9235.