Short-Circuit Protection Circuit With Current Slope-to-Digital Conversion Short-Circuit Detection and Adaptive Soft Turn-Off

Abstract

A short-circuit protection circuit is proposed for power electronic systems employing silicon carbide metal–oxide–semiconductor field-effect transistors. The circuit incorporates two innovative techniques: a current slope-to-digital conversion for short-circuit detection and an adaptive soft turn-off based on transistor input capacitance sensing. A low-side gate driver incorporating the proposed circuit was implemented on an integrated chip for functional verification. The gate driver reliably protects a wide range of silicon carbide metal–oxide–semiconductor field-effect transistor devices with current capacities from 10 to 95 A during short-circuit conditions. It ensures that the drain–source voltage overshoot remains below 14.5% of the drain–source voltage while achieving a consistent response delay of approximately 750 ns for short-circuit detection and a turn-off time of approximately 500 ns for soft turn-off operation.

Keywords

• Monolithic integrated circuits
• silicon carbide MOSFET
• short-circuit detection
• short-circuit protection
• soft turn-off