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This article introduces a silicon carbide (SiC)-based high-voltage silicon-controlled rectifier (HV-SCR) for on-chip electrostatic discharge (ESD) protection. The SiC HV-SCR is formed by implanting a $\text{p}^{+}$ region into the n-well of SiC laterally diffused metal-oxide semiconductor (LDMOS) structures. Both LDMOS and HV-SCR structures were characterized using a transmission line pulse (TLP) system to investigate their ESD behaviors. The TLP measurement results show that the trigger voltage (${V}_{\text {t1}}$) of the SiC HV-SCR is $\sim 230$ V and has minor dependence on the drift length. The ${V}_{\text {t1}}$ value of the SiC LDMOS decreases from 224 to 202 V when its drift length decreases from 6 to 4 $\mu \text{m}$. TLP measurements with 500- $\Omega $ impedance were conducted to obtain an accurate holding voltage (${V}_{\text {h}}$) and failure current (${I}_{\text {t2}}$) of HV-SCR and LDMOS. Relatively high ${I}_{\text {t2}}$ (i.e., 33 mA/ $\mu \text{m}$) of the HV-SCR structure was observed, which is much stronger than the LDMOS structure (i.e., 0.2 mA/ $\mu \text{m}$). The ${V}_{\text {t1}}$ and ${V}_{\text {h}}$ values of HV-SCR were also investigated with varying gate bias voltages. Moreover, technology computer-aided design (TCAD) simulations of the SiC HV-SCR and LDMOS were carried out to further understand their ESD behaviors. [ABSTRACT FROM AUTHOR]

This paper describes a silicon carbide pulse width modulation (PWM) signal generator in the 1.2 μm HiTSiC CMOS process developed by Raytheon Systems Ltd. The design features a 6-b binary input, which allows for setting a system's duty cycle. The results presented in this paper utilize a field programmable gate array board in the test setup to dynamically set the duty cycle by controlling each bit. A control current is also available to give the user added flexibility for tuning the duty cycle. Experimental results show the duty cycle range of the PWM generator to be between 4.7% and 95.2% at 400 °C. Sustained operation of the circuit is demonstrated over a period of 50 h at 300 °C. Finally, the PWM generator is evaluated in the operation of a boost converter. [ABSTRACT FROM PUBLISHER]