Mastering Common Mode Transient Immunity (CMTI) for Isolated Gate Drivers
With the exponential progress and adoption of next generation power semiconductor devices, i.e. SiC and GaN, customer end equipment is targeting higher switching frequency/density. It is especially challenging to take advantage of these achievements without sacrificing the system robustness because these new power semiconductors can have over 2× the dv/dt and over 5× the di/dt during turn on/turn off transients when compared to conventional MOSFETs and IGBTs. This presentation will start by explaining these challenges with bench waveform measurement comparison, then, isolated gate driver and the benefits are identified by addressing the key specifications with the related noise immunity. Finally, a deep dive of the dv/dt (CMTI) and di/dt for isolated gate driver will be summarized with issue definition, standard requirement, bench characterization, and system design solutions using TI’s isolated gate driver family.