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Dynamic electrothermal circuit simulator models are developed for silicon carbide power diodes. The models accurately describe the temperature dependence of on-state characteristics and reverse-recovery switching waveforms. The models are verified for the temperature dependence of the on-state characteristics, and the di/dt, dv/dt, and temperature dependence of the reverse-recovery characteristics. The model results are presented for 1500 V SiC Merged PiN Schottky (MPS) diodes, 600 V Schottky diodes, and 5000 V SiC PiN diodes. The devices studied have current ratings from 0.25 A to 5 A and have different lifetimes resulting in different switching energy versus on-state voltage trade-offs. The devices are characterized using a previously reported test system specifically designed to emulate a wide range of application conditions by independently controlling the applied diode voltage, forward diode current, di/dt, and dv/dt at turn-off. A behavioral model of the test system is implemented to simulate and validate the models. The models are validated for a wide range of application conditions for which the diode could be used. Index Terms--Circuit simulation, diode model, merged PiN Schottky, PiN, power diode, reverse recovery, Schottky, SiC.

A new class of MOS-gated power semiconductor devices Cool MOS (Cool MOS is a trademark of Infineon Technologies, Germany) has recently been introduced with a supreme conducting characteristic that overcomes the high on-state resistance limitations of high-voltage power MOSFETs. From the application point of view, a very frequently asked question immediately arises: Does this device behave like a MOSFET or an insulated gate bipolar transistor (IGBT)? The goal of this paper is to compare and contrast the major similarities and differences between this device and the traditional MOSFET and IGBT. In this paper, the new device is fully characterized for its: 1) conduction characteristics; 2) switching voltage, current, and energy characteristics; 3) gate drive resistance effects; 4) output capacitance; and 5) reverse-bias safe operating areas. Experimental results indicate that the conduction characteristics of the new device are similar to the MOSFET but with much smaller on-resistance for the same chip and package size. The switching characteristics of the Cool MOS are also similar to the MOSFET in that they have fast switching speeds and do not have a current tail at turn-off. However, the effect of the gate drive resistance on the turn-off voltage rate of rise (dv/dt) is more like an IGBT. In other words, a very large gate drive resistance is required to have a significant change on dv/dt, resulting in a large turn-off delay. Overall, the device was found to behave more like a power MOSFET than like an IGBT. Index Terms--Cool MOS, high-voltage MOSFET, power MOSFET.

Techniques are described for validating the performance of insulated gate bipolar transistor (IGBT) circuit simulator models for soft-switching circuit conditions. The circuits used for the validation include a soft-switched boost converter similar to that used in power-factor correction, and a new half-bridge testbed that is specially designed to examine the details of IGBT soft-switching waveforms. The new testbed is designed to emulate the soft-switching circuit conditions of actual applications circuits, while allowing the easy change of IGBT operating conditions. The testbed also eliminates the problems of commutating diode noise and IGBT temperature rise found in actual application circuits. Simulations of IGBT models provided in circuit simulator component libraries are compared with measurements obtained using these test circuits for the soft-switching conditions of zero-voltage turn-on, zero-voltage turn-off, or zero-current turn-off. Finally, the results are summarized by comparing the switching energies for the various measurements and simulations presented in this work. Index Terms--Circuit simulation, insulated gate bipolar transistor, model validation, power electronics, soft switching, switching energy.

The electrical performance of silicon carbide (SiC) power diodes is evaluated and compared to that of commercially available silicon (Si) diodes in the voltage range from 600 V through 5000 V. The comparisons include the on-state characteristics, the reverse recovery characteristics, and power converter efficiency and electromagnetic interference (EMI). It is shown that a newly developed 1500-V SiC merged PiN Schottky (MPS) diode has significant performance advantages over Si diodes optimized for various voltages in the range of 600 V through 1500 V. It is also shown that a newly developed 5000 V SiC PiN diode has significant performance advantages over Si diodes optimized for various voltages in the range of 2000 V through 5000 V. In a test case power converter, replacing the best 600 V Si diodes available with the 1500 V SiC MPS diode results in an increase of power supply efficiency from 82% to 88% for switching at 186 kHz, and a reduction in EMI emissions. Index Terms--Fast recovery rectifier, merged PiN Schottky diode, PiN diode, reverse recovery, SiC diode, SiC rectifier.

The internal failure dynamics of the insulated gate bipolar transistor (IGBT) for unclamped inductive switching (UIS) conditions are studied using simulations and measurements. The UIS measurements are made using a unique, automated nondestructive reverse-bias safe operation area test system. Simulations are performed with an advanced IGBT circuit simulator model for UIS conditions to predict the mechanisms and conditions for failure. It is shown that the conditions for UIS failure and the shape of the anode voltage avalanche-sustaining waveforms during turn-off vary with the IGBT temperature, and turn-off current level. Evidence of single- and multiple-filament formation is presented and supported with both measurements and simulations. Index Terms--Avalanche, current constriction, failure, filament, insulated gate bipolar transistor, modeling, nondestructive testing, reverse-bias safe operation area.

Presents a study which compared the major similarities and differences between a class of metal-oxide-semiconductor (MOS)-gated power devices and the traditional metal-oxide-semiconductor field-effect transistor and insulated gate bipolar transistor. Structure of MOS-gated devices; Conduction characteristics of the MOS-gated devices; Switching characteristics; Gate drive resistance effects; Comparison of output capacitance.

Proposes a methodology for the validation of compact thermal models of electronic packages which utilizes data and simulations obtained from a simple but realistic system containing the package. Thermophysical properties used for computations; Heat transfer budgets for thermal models; Compact modeling strategies; Conclusion.