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ADG5433 generates voltage spike at output while switching at 100KHz

Hi All,

I have used Analog switch to generate 100KHZ square with variable voltage range from 1V to 15V.

While generating square wave, i am getting voltage spikes on both falling/rising edge which i have tried RC filter to remove at output of analog switch but still not able to remove completely.

please find attached image for the same where you can see edge noise at falling edge of square.

I am applying this output voltage waveform though unity gain buffer amplifier to 600Ohms resistance and measuring current flowing through this load using AD8421 amplifier.

Due to edge noise generated by switch, i am getting very large output voltage spike at output of instrumentation amplifier. Due to this i am not able to measure right voltage through my controller ADC.

I would like to remove this voltage spike at switch and instrumentation amplifier.

For your information i have attached snapshot of waveform and partial schematic for the same.

please, do suggest me your expert input for the same to resolve this issue.

  • Hello VishalP,

    This looks like charge injection. It is not clear from your schematic section what the load on the output of the switch is and the reason for choosing the ADG5433.

    If you do not require the low on resistance of the ADG5433, I would recommend the ADG5233 which is the same configuration and package; this device is optimised for low charge injection.

    If your supplies for the switch will not exceed ±16.5V, then you could also use the ADG1233.