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UCC21710QDWEVM-025: SiC drive with +15V/-8V

Part Number: UCC21710QDWEVM-025
Other Parts Discussed in Thread: UCC21710-Q1, SN6505B, UCC14240-Q1

Hello team,

I would like to drive gate of SiC mosfet with +15V/-8V and control it with faster than 200kHz switching.

I think we can use UCC21710-Q1 for the use.

Can its EVM be used for driving SiC mosfet with the condition by removing onboard DCDC output and adding external +15V and -8V instead?

Or, could you let me know if there is other device's EVM that can set any gate voltage without adding a modification to EVM?

Best regards,

  • Taketo-san, 

    I think we can use UCC21710-Q1 for the use.

    This is a great choice for SiC

    Can its EVM be used for driving SiC mosfet with the condition by removing onboard DCDC output and adding external +15V and -8V instead?

    Yes, this is no problem. We have actually done this for internal testing as well. 

    There is another option which allows you to keep the isolated bias supplies, and may be simpler. To some extent the EVM was designed with this functionality in mind. 

    Normally, the Input supply goes to the driver and both DCDC converter, but you see that on our power connection we have 2 test points. Normally they are connected since R8 is populated. If we remove 

    R8, and R2, we can provide power to the driver and each SN6505b converter seperately. The advantage of this is, since the SN6505b is open loop, you can connect the supply to it directly and adjust the voltage on PSU and it will change the DC DC converter op

    Note that after making this modification, you might need to hard-tie EN to VCC1. Sometimes the window comparator freaks out. The easiest way to accomplish this is to remove U5. 

    Or, could you let me know if there is other device's EVM that can set any gate voltage without adding a modification to EVM?

    Adjustable output voltage is commonly requested. We plan to release an EVM with this functionality in 2022 that will allow easy change changing resistor ratio only. 

    Other than that we do not have an option to do this without modification unless you want to use a second EVM (UCC14240-Q1 EVM for example). 

    If this answers your question please let me know by pressing the green button. 



    Best

    Dimitri