Other Parts Discussed in Thread: UCC28951
Hello
We are developing DC-DC PSU with input voltage range 600-800VDC and output voltage 60VDC@10А using UCC28950. With asinchronous rectifier system works without problems, but power dissipation is too high.
With sinchronous rectifier we got a problem: when SR starting to work we gets a huge noise on all nets - on output, on control nets and even UCC28950 power input. As result, it kills controller. What can cause it?
Oscillograms with enabled SR:
- SR transistors gates with SR enabled before stabilization started
2, 3. Output with asynchronous rectifier without load
4, 5. Output with asynchronous rectifier loaded with 1A
6, 7. Output with SR enabled after stabilization started (load 1A)
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