High Impedance High Bandwidth High Immunity Voltage Dividers

Abstract:
Resistive voltage dividers are commonly used for voltage sensing. High impedance voltage dividers are used in medium and high voltage and in low power applications but are sensitive to external AC electric fields. Placing a shield near the divider significantly reduces the divider frequency bandwidth due to stray capacitance to the shield. This paper presents a compact high impedance voltage divider (tens of megaohms) with a large frequency bandwidth (up to at least ten Megahertz) and a good immunity to external electrical AC fields, embedded in an FR4 substrate.