SBAA558 October   2022 ADS9218 , ADS9219

 

  1.   Abstract
  2.   Trademarks
  3. 1Driving Input Transients on Traditional SAR
  4. 2Driving High-Input Impedance SAR
    1. 2.1 Choosing the Antialiasing Filter
    2. 2.2 Driving the Reference Input
  5. 3Summary

3 Summary

The ADS9218 is an example of a modern SAR with an integrated buffer for the voltage input and the reference input. This type of device has an advantage over traditional SAR devices because there is no transient current demand on the reference or voltage input. This makes choosing the amplifier and filter cutoff on the voltage input easier and allows for more flexibility in the design. Furthermore, the voltage reference does not require special wide bandwidth voltage reference or external reference buffers. Overall, the modern SAR approach simplifies the design process, reduces circuit complexity, and provides more design flexibility.