PMP21529: The HO is abnormal and the LO is normal

Part Number: PMP21529
Other Parts Discussed in Thread: UCC27211A, , UCC27211

Tool/software:

Hi Experts,

This is Skylar responsible for GREE. GREE refers to our reference design PMP21529. GREE shorten Q4 and removed Q3 first to test UCC27211A's function. MCU is set as 80% and 20%.

Here are the HO and LO waveforms as below.

  

After suffering the abnormal output of HO for a while, the UCC27211A is damaged which causes the 12V VDD is shorten.

Could you pls help on this issue? Thanks!

BR,

Skylar

  • Hi experts,

    Adding more information:

    1. The deadtime is 4%, PWM frequency is 75khz.

    2. When only connecting 12V VDD, the HO and LO could function normally and Vcboot also has stable 12V.

    But when both having 12V VDD and 48V Vdcbus, the HO and Vcboot could not function normally. The HO waveform is as below.

    Vcboot could not reach to 12V anymore. 

    Here is the layout as below.

      

    Pls feel free to give me advice. Thanks!

    BR,

    Skylar

  • Hi Skylar,

    We have already discussed this through email, this has nothing to do with our PMP21529 reference design, PMP21529 will never run into this test condition. This is something related to the UCC27211 gate driver and the way how it was tested, please consult with driver team, they are the right person for this question. Or you can submit a new E2E question and put UCC27211 (not PMP21529) in the title.  

    Regards,

    Bosheng