Analysis of ADC System Distortion Caused by Source Resistance

Abstract: Analog-to-digital converter (ADC) data sheets and application typically recommend driving their inputs with a low source impedance. This application note explains the possible effects such as increased gain error and distortion when using high impedance to drive an ADC without a buffer.
Maxim > App Notes > A/D and D/A CONVERSION/SAMPLING CIRCUITS

Keywords: ADC, analog to digital converter, voltage divider, distortion, gain error, high impedance, low Mar 25, 2003
impedance, sampling capacitor, time constant, a/d converters

APPLICATION NOTE 1948
Analysis of ADC System Distortion Caused by Source Resistance

Abstract: Analog-to-digital converter (ADC) data sheets and application typically recommend driving their
inputs with a low source impedance. This application note explains the possible effects such as increased gain
error and distortion when using high impedance to drive an ADC without a buffer.


Analog-to-digital converter (ADC) users have been instructed by endless data sheets and application notes to
drive their ADCs with a low source impedance. However, these i