A Fast ON-State Drain-to-Source Voltage Amplifier for the Dynamic Characterization of GaN Power Transistors

A high-speed ON-state voltage amplifier with clip-ping capability for the accurate dynamic characterization of fast-switching wide-bandgap power transistors is presented. The fast reaction time and the tunable gain make it suitable for the characterization of a wide range of state-of-the-art power transistors. The novelty of the circuit lies in the best-in-class response time of 26.7 ns, which is achieved through a recovery acceleration circuit. A bandwidth of 142 MHz is achieved. The voltage gain is helpful to improve the measurement range utilization of the oscilloscope. The circuit function has been validated with static transfer measurements and dynamic double-pulse tests on a gallium nitride power transistor.