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Differential signal amplify

Differential signal from Resistance  bridge(P3).  ADC is ADUC7060 Internal  .Consideration 4-20mA Circuit ,the power dissipation very low.Can only use ADA4051-2 Build Differential signal amplify. The scheme is ok?  In the debug,ADC1 ADC0 have 50HZ vpp 200mV Noise.Needs to go a step further filter?

How to filter out the noise(50Hz).

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  • Harry:

           Thank you for your reply,What are the characteristics of the bridge?(Ceramic Pressure Sensors  )  Impedances(10K±20%)

    Re- establish parameter (look  Schematic.jpg)   Differential signal amplify'  95  times:

    For Common-Mode Rejection  and  Normal-Mode Rejection 50 Hz/60 Hz1
    On ADC Input:

    ADC :50 Hz/60 Hz ± 1 Hz, 16.6 Hz and 50 Hz update rate, chop on.(choose  16.6 Hz );

    ADCIN1 ADCIN2 waveform measurement (4.bmp)50Hz ;waveform measurement at the between of  C17(5.bmp) ;   waveform measurement at the between of  ADC0  ADC1  (6.bmp )  100Hz.      50Hz  to 100Hz  change(Why ?  )

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  • Harry:

           Thank you for your reply,What are the characteristics of the bridge?(Ceramic Pressure Sensors  )  Impedances(10K±20%)

    Re- establish parameter (look  Schematic.jpg)   Differential signal amplify'  95  times:

    For Common-Mode Rejection  and  Normal-Mode Rejection 50 Hz/60 Hz1
    On ADC Input:

    ADC :50 Hz/60 Hz ± 1 Hz, 16.6 Hz and 50 Hz update rate, chop on.(choose  16.6 Hz );

    ADCIN1 ADCIN2 waveform measurement (4.bmp)50Hz ;waveform measurement at the between of  C17(5.bmp) ;   waveform measurement at the between of  ADC0  ADC1  (6.bmp )  100Hz.      50Hz  to 100Hz  change(Why ?  )

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