COMPONENT TOLERANCES

摘要

Resistor tolerances in input attenuators create dc errors, and capacitors in the attenuators create a significant amount of ac errors (Figure A). For this reason, you must use discrete capacitors in the input attenuator to swamp out all the stray capacitance in the PCS (prtnted-circuit board) and in the mul-tiplexer's input pins. Placing three capacitors in parallel with the resistors makes an ac-voltage divider alongside the dc-voltage divider that the resistors create.