Reproducing Power Hysteresis With Circuit Envelope Simulation

Power collapse and related hysteresis have been observed for pHEMT switch in its on state when the input power is swept in a certain power range. The abnormal high power behavior can be explained in terms of self-heating and the temperature dependence of the device performance. By incorporating self-heating and temperature dependence into a simplified model, power collapse is reproduced in harmonic balance simulation. A novel simulation scheme is then proposed to simulate the power hysteresis. By representing the power sweep in the measurement with a time-varying power source, the power hysteresis has been successfully reproduced in circuit envelope simulation.