I want to drive a 650V 21A SiC mosfet at 100kHZ. Would this mosfet driver be able to drive the mosfet?

How can I find Gate charge of the mentioned mosfet gate driver?

The mosfet I am planning to use is SCT3120ALHR. Please suggest if this driver will be able to drive the mosfet.

If not, then please do suggest what other driver and mosfet can I use in place of these.

I will do simulations of the components.


How can I find Gate charge of the mentioned mosfet gate driver?

You won't. The gate charge is a characteristic of the device you are driving. To turn it on you must transfer that charge to the gate, to turn it off you must remove that charge.

How fast you want to do this (your switching frequency) will determine the current that will flow. The peak current will be driven by the gate resistance

Based upon your system needs, you can then design an appropriate gatedrive.

As to whether your shortlisted driver will work... Yes BUT how well depends on your switching frequency and the peak current you want to hit the MOSFET with

SCT3120ALHR Gate charge: 38nC for an 18V swing on-die gate resistance: 18R

NCP51705 Peak current 6A

An NCP51705 driving an SCT3120ALHR will need a minimum output drive capability of: 1A for an 18V swing. ✔

The design case is 100kHz. The NCP51705 can switch at 500kHz ✔

At 500kHz the needed power to be sourced is: 68mW ✔

This driver chip appears to have the capability to transfer the needed charge at the required rate

  • \$\begingroup\$ Thank you. It means that there is only current. Higher the current, higher the charge. \$\endgroup\$ – mANmAN01 Jul 9 at 8:15
  • 1
    \$\begingroup\$ no, the MOSFET needs charge. You must charge and discharge the gate capacitance to permit switching. \$\endgroup\$ – JonRB Jul 10 at 18:01

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