SBAA507 March   2021 ADS8578S , ADS8584S , ADS8586S , ADS8588H , ADS8588S , ADS8598H , ADS8598S , ADS8661 , ADS8664 , ADS8665 , ADS8668 , ADS8671 , ADS8674 , ADS8675 , ADS8678 , ADS8681 , ADS8684 , ADS8684A , ADS8685 , ADS8688 , ADS8688A , ADS8688AT , ADS8689 , ADS8691 , ADS8694 , ADS8695 , ADS8698 , ADS8699 , OPA2990 , OPA4990 , OPA990

 

  1.   1
  2.   Design Description
  3.   Specifications
  4.   Design Notes
  5.   Component Selection
  6.   DC Transfer Characteristics
  7.   Simulation Verification for Floating Input
  8.   AC Transfer Characteristics
  9.   Noise Simulation
  10.   Stability Simulation
  11.   Design References
  12.   Design Featured Devices

AC Transfer Characteristics

The bandwidth for this circuit is limited by the RC filter (R3||R4 and C1). The hand calculation and the simulated results compare well (hand calculation fC = 17.2kHz, simulated fC = 17.2kHz). See the Op Amp Bandwidth video series for more details on this subject. Note that the internal 2nd-order low pass filter of the ADS8681 has a 15-kHz bandwidth. The bandwidth for this circuit is mainly dominated by the low-pass filter of the ADC.

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