This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

CSD18510Q5B: MOSFET heatsink design

Part Number: CSD18510Q5B

Hello everyone,

I wanted to build an asymmetric half-bridge inverter with MOSFETs that could support 24V and 70A. I found this MOSFET:  https://www.ti.com/product/CSD18510Q5B which seems to be suitable for my application. My question concerning heat dissipation of the MOSFET. How I can choose or design the heatsink knowing that I must have a very light weight of final circuit.

Thank you for your help

Best regards

Yakoub.

  • Hello Yakoub,

    Thanks for your interest in TI FETs. The primary path to remove heat from this 5x6mm SON package is thru the large thermal pad (drain) on the bottom of the package and into the PCB. It is possible to attach a heatsink to the top of the package but the thermal impedance, Rθjc(top), is about 8°C/W compared to 0.8°C/W for Rθjc(bottom). Another alternative it to attach the heatsink to the opposite side of the PCB from the FETs using thermal vias to provide a path from the FET packages to the heatsink. TI has FET selection tools available to estimate the power loss in the FETs available on the MOSFET Support & training page at the link below. These include 3-phase BLDC motor drive and sync buck tools. There are also blogs and technical articles available on this page that explain how TI tests and specs thermal impedance in our datasheets and estimates for maximum power dissipation by package. Please review and let me know if you have any additional questions.

    Best Regards,

    John Wallace

    TI FET Applications

    https://www.ti.com/power-management/mosfets/support-training.html

  • I see today most inverters are based on MOSFETs. These inverters are very efficient and have very less resistance path between source and drain terminal.

    I cannot say anything about the heatsink because technically I am not too good at.

  • Pawan,

    John is out and back next week. So in his absence I will try to help.

    If you have concerns on thermals and design. Have you thought of looking at ti.com to try and find a reference design that maybe close to your application requirements?

    On example of a high current motor inverter is here that may be of interest.

    https://www.ti.com/tool/TIDA-00774?keyMatch=&tisearch=search-everything&usecase=refdesign

    Although the ref design says up to 21V, it does use 40V MOSFETs which is normally find for a peak Vin of 24V. You can look at the literature and see the layout as a guide.

    Best Regards

    Chris

  • Hello Pawan,

    Following up to see if your issue has been resolved. Please let us know if you need additional information. If not, then I will close this thread in 24 hours.

    Best Regards,

    John Wallace