Recommendation of Gate Driver Power - GM3 Module

shawn

Customer is evaluating CAB006M12GM3 and its gate driver, as the target fsw is 100kHz(hard-switching), according to the gate driver power dissipation fomula: P=Qg*fsw*(Vdd-Vss), the required Power of gate driver is 708nC*100kHz*[15V-(-3V)]=1.3W.

So if considering a reasonable margin, what's the power we should recommend cutomer to design? And if there is any margin design guideline we can follow?

Thanks!

DanMartin

Hi Shawn,

Margin is really set by a few factors. For instance, in your above caluclations, you're only accounting for the draw to actuate the gates, this doesn't included power requirements of any secondary components, such as the driver IC or any auxiliary circuits being fed by the power supply. After that, there is the consideration of ambient temperatures. Since there is a direct correlation between temperature rise and and power processed, the design should take into account the maximum expected ambient temperature as well as the thermal resistance of the power supply to ambient. If the design uses an all-in-one style brick supply, they typically list on the datasheet power vs. ambient temperature for use in de-rating calculations.

BR,

Dan

shawn

Hi Daniel,

Last week there seems some issue on the forum that we were not able to login...

Thanks for your explanation. Understood that we should take more factors into consideration, rather than a simply fomula. I will support customer to fully evaluate its gate driver design by your suggestion.

Thanks.