Automotive dual-channel SiC MOSFET gate driver reference design with two-level shutdown protection

This reference design is an automotive-qualified isolated gate driver solution that drives silicon carbide (SiC) MOSFETs in a half-bridge configuration. This design provides two push-pull bias supplies for dual-channel isolated gate drivers, each providing +15V and –4V output voltages and 1W output power. The gate driver is capable of 4A peak source current and 6A peak sink current. The driver implements reinforced isolation and can withstand 8kV peak isolation voltage and 5.7kV RMS isolation voltage as well as common-mode transient immunity (CMTI) of over 100V/ns. This reference design includes a two-stage shutdown circuit that protects the MOSFET against voltage overshoot during short circuit conditions. DESAT detection threshold and second stage shutdown delay time are configurable. This design uses an ISO7721-Q1 digital isolator to connect the fault and reset signals. The overall design adopts a compact double-layer PCB board of 40mm × 40mm.

characteristic

• ● Compact dual-channel gate driver solution for driving SiC MOSFETs in half-bridge configuration
• ● 4A peak source current and 6A peak sink current drive capability, suitable for driving SiC MOSFET, Si MOSFET and IGBT, with switching frequency up to 500kHz
• ● Compact and efficient built-in isolated bias supply (with 15V and –4V outputs)
• ● Discrete two-stage shutdown for short-circuit protection with adjustable current limit and delay (blanking) time
• ● Provides high CMTI greater than 100V/ns and enhanced 8kV peak voltage and 5.7kV RMS voltage isolation