TDR Measurement Method for Voltage-Dependent Capacitance of Power Devices and Components

The measurement of circuit parasitic parameters and the evaluation of equivalent circuit models are both necessary techniques for noise analysis and the circuit design of high-speed power electronics circuits. Recently, time-domain reflectometry (TDR) has emerged as a technique for measuring circuit parameters. This paper proposes a TDR method for measuring the voltage- dependent capacitance of power devices and passive components. This method can be used to measure the capacitance on any dc bias voltage. The C_oss value of MOSFETs with V_DS = 0-350 V, the anode-cathode capacitance under reverse bias condition on SiC diodes, and voltage-dependent capacitances of ceramic capacitors were measured in experiments.