SMPS using UC3842 - And related problems

vantusaonho

Junior Member

Offline

Posts: 52

Thank You
-Given: 22
-Receive: 21

Re: SMPS using UC3842 - And related problems

« Reply #50 on: January 07, 2013, 02:22:37 14:22 »

I think it due to core saturation. Because with the same board, I tried with 110VAC, it work fine. But for 220VAC, it burned fuse and mosfet. Do you think same to me?


	Logged

vantusaonho

Junior Member

Offline

Posts: 52

Thank You
-Given: 22
-Receive: 21

Re: SMPS using UC3842 - And related problems

« Reply #51 on: January 09, 2013, 01:38:25 01:38 »

Job done Thanks All


	Logged

Faros

Senior Member

Offline

Posts: 254

Thank You
-Given: 141
-Receive: 178

Re: SMPS using UC3842 - And related problems

« Reply #52 on: January 09, 2013, 03:42:08 03:42 »

Quote from: vantusaonho on January 09, 2013, 01:38:25 01:38

Job done Thanks All

@vantusaonho
You owe members who tried to help you some explanation of "how your job is DONE?!!" , this way you may find someone answering your request next time.


	Logged

vantusaonho

Junior Member

Offline

Posts: 52

Thank You
-Given: 22
-Receive: 21

Re: SMPS using UC3842 - And related problems

« Reply #53 on: January 09, 2013, 11:53:38 11:53 »

Oh! I wind another transformer again with less than primary winding in turns. And note that with 220VAC, the DC voltage after rectifier will be 220*sprt(2) - 10% margin - 20V (ripple and drop diode voltage) = 260V. From that, the turns for primary winding will be decrease as a result.
More turns more flux flow. So core saturation will reach quickly and leading to smoke mosfet and fuse. That is real problem
I hope you get success as me.


	Logged

Pages: 1 2 [3] All

« previous next »

	Welcome, Guest. Please login or register. Did you miss your activation email?	April 19, 2024, 06:50:30 18:50
		Login with username, password and session length

	Author	Topic: SMPS using UC3842 - And related problems (Read 19421 times)
0 Members and 1 Guest are viewing this topic.