Wolfspeed Power Applications Forum

Wolfspeed Technical Community:

SpeedFit™ Design Simulator

Simulate and evaluate the performance of SiC-based power circuits and determine the right SiC device in seconds.

Start a Simulation

Categories

RC Snubber Design

Options
Maideen
Maideen Contributor Level 1
edited September 3 in Module Products

For this wplf speed power module (CAB6R0A23GM4T) we have calculated snubber calculation in this way. Could you please verify is it correct. If not, please suggest the right way?
Our ringging frq is 20MHz
Csn=Ls*Ipk^2/Vsn^2 = 30n*180^2/1800^2 = 300pf
Rsn= Sqrt(Ls/Csn)= Sqrt(30n/300p)=10 Ohm
Psn=Csn*Vsn^2*fsw=300p*1800^2*25k=24.3W

Comments

  • Forum_Moderator
    Forum_Moderator Wolfspeed Employee - Contributor Level 5
    Options

    Thank you for your post, it has been approved and we will respond as soon as possible.

  • CFlack
    CFlack Wolfspeed Employee - Contributor Level 1
    Options

    Maideen,

    These calculations make sense from a theoretical perspective. In practice, a capacitor several times larger than the output capacitance is typically required. You may find this article to be of use: Power Tips: Calculate an R-C snubber in seven steps.

    I would suggest initially simulating your design using our LTspice models. As the design progresses, you may choose to evaluate your design in the lab with our 2300 V WolfPACK™ GM SiC Modules Evaluation Kit, which includes pads for device RC snubbers and a DC bus snubber.

    Please let us know if you have further questions. Thanks!

Sign In or Register to comment.