16W design using TOP257PN
Posted by: sudharshana
on
Hello Sir,
I have developed 16W power supply using TOP257PN with input voltage range from 35 VAC to 625 VAC with multiple outputs. I request you to review the design and give the comments. Thanks in advance.
Files
| Attachment | Size |
|---|---|
| 16W PSU.pdf | 27.87 KB |
Comments
Thanks a lot for review. Whether this design works for 3 phase 3 wire i.e only RYB inputs alone?
Hi,
Attached is the circuit. In this power supply is not starting.If i replace 3.9V zener by 3.3V am getting 3.8V in the main winding output instead of 5V output required. I replaced zener feedback by TL431 power supply is working fine and taking load also. what is the problem with zener feedback.Expecting for the reply.
You may need a 20pf cap across zener chain ( Z15-Z22) to guarantee start-up at low VAC. Otherwise desing look reasonable.