ADUM3123 Fsw maximum question?

i see datasheet, the fsw maximum is 1MHz?   if we need to work to 6.78MHz, that is ok?

currently i need a gate drive for drive wolfspeed "C3M0065090D" (Vgs-on=15V, Vgs-off=0V), our application is "wireless charger" and topology is "class-EF".

so i only use 1pcs SiC MOSFET on low side, so i don't isolation of gate drive, but it need switching frequency to 6.78MHz.

ADUM3123 is ok?   or you have suggest MOSFET driver for it?


  • Hello,

    The ADuM3123 is capable of operating at 6.78 MHz, but there will be significant self heating within the IC. The ADuM3123 also has a minimum pulse width of 50 ns, so if the design requires pulses shorter than that, there may be an issue.

    The ADuM3123 has a CMTI of >25 kV/µs. Will the ground of your EF converter see fast dv/dt excursions? Since is it on the lowside, this is unlikely, but I just want to point out the CMTI of the part.

    Operating the ADuM3123 is possible at those frequencies, but it is not recommended.

    Other parts to looks at are the ADuM4121 and ADuM4120. They don't have an explicit fsw written in the datasheet, but operation above 500 kHz will produce higher Iq. I have successfully operated ADuM4121 and ADuM4120 units at 6 MHz in the past, but again the self heating will be the main concern.

    What ambient temperature does this application target?