A capacitively coupled SiC MOSFET gate driver using dv/dt enhanced OOK transmitter with CMTI of 220V/ns

Abstract

This paper presents a high Common Mode Transient Immunity (CMTI) modulation circuit for a capacitively coupled gate driver. It proposes an enhanced on-off keying (OOK) transmitter architecture with integrated common-mode (CM) substrate modulation. Through collaboration with the CM interference detection circuit, transmission accuracy and CMTI are improved without additional delay.
Test results show the prototype driver achieves 220 V/ns CMTI, 20 ns propagation delay, the rise and fall times of 10 ns and 12 ns respectively under 15 V supply voltage, and the rise and fall time of 22 ns and 24 ns respectively under 30 V supply voltage with 2.5 MHz frequency and 3.5 nF load.