UCC2803-Q1: Troubleshooting isolated flyback converter

Ambuj Agarwal

Part Number: UCC2803-Q1

Hello,

We have designed an isolated flyback converter based on UCC2803 based on the inputs from WEBench.

However, we are facing a lot of issues in bringing up the hardware. I am attaching our design here. The problem is that I am not getting proper gate drive. Where do you think we got it wrong. Please suggest.

2402.15V converter.pdf

over 4 years ago

0 Ambuj Agarwal over 4 years ago

Intellectual 290 points

Please find snapshots of the waveforms at gate drive, output, and feedback pins attached here90ohm load output.pdf feedback pin.pdf Load_Gate_Drive.pdf No_Load_Gate_Drive.pdf No_Load_Output.pdf Ref_Pin.pdf for reference.

0 Hong Huang over 4 years ago in reply to Ambuj Agarwal

TI__Guru 59075 points

Hi,

Can you specify, on each waveform, where in circuit you made measurement?

0 Mukesh kesharwani over 4 years ago in reply to Hong Huang

Prodigy 30 points

Hi Huang,

Please co-relate the waveform with the attached schematic.

I am marking the schematic reference points in the waveform.

0 Mukesh kesharwani over 4 years ago in reply to Mukesh kesharwani

Prodigy 30 points

Hi Huang,

Any update on the issue.

Please help me to get it resolved ASAP.

Waiting for your quick support.

Thanks,

Mukesh

0 Hong Huang over 4 years ago in reply to Mukesh kesharwani

TI__Guru 59075 points

can you change c24 to 100nF and R34 to 1k then test and measure the same waveform to see any improvement?

Because of the holidays, TI E2E™ design support forum responses will be delayed from Dec. 25 through Jan. 2. Thank you for your patience.

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UCC2803-Q1: Troubleshooting isolated flyback converter