A novel broadband capacitor voltage divider for measurement of ultrafast square high voltage pulse transmitted in transmission line

This paper studies a new type of broadband capacitive voltage divider, which is used to measure the high voltage square wave pulse with sub-nanosecond front in a transmission line. The low-frequency characteristics of traditional capacitive dividers are extended by adding sampling resistors, and the high-frequency gain caused by stray capacitors of sampling resistors is eliminated by adding compensation capacitors, which greatly broadens the bandwidth of capacitive dividers. The findings show that when the sampling resistance is 6.1 k Omega and 12 k Omega and the equivalent grounding capacitance is about 15 pF and 30 pF, respectively, the bandwidth of the divider is 180 kHz to 2 GHz and 100 kHz to 2 GHz, which can meet the test requirements of the high voltage square wave pulse with sub-nanosecond front and dozens of nanosecond pulse width.