Issue with FlyBack AC/DC Converter - Output 5V, 500mA

Posted by: morethegr8 on 03/22/2016

Im using LinkSwitch II - LNK615DG for my design.

Problems:

When i connect this circuit to AC mains - 230VAC. Bridge diode and fuse Blows.
I replaced MB8S with General purpose diodes 1N4007 and i started circuit with series test lamp setup.
Now the circuit shows output of 1.8 ~ 2.45 VDC and is not stable.

Kindly help me debug the circuit as i don't have Variac and working at 230VAC is highly dangerous.

Thanks in advance.

Design Reference:
3.25 W CV/CC Charger Using LinkSwitchTM-II
That Meets New 2011 European Standards.

Comments

Hello morethegr8,

Thank you for using PI productor.

I cannot open the attachment. can you give us the schematic. in this way, we can dig in more.

Best Regards

Jia

Thanks,

Jia

I have made certain changes in the transformer winding.

Now i m able to get 8V output. But its still not as per design reference.

I have attached Schematics in pdf form.

Thanks for the follow up.

Attachment	Size
PS5V500 BCKUP.pdf (21.4 KB)	21.4 KB

Hello morethegr8,

the schematic looks to be OK if you already replced MB8S to a 1000V reverse voltage rating diode.

The next step is the transformer design. Did you use our PIxls to check the transformer design? If it passes all the requirement, which means no warning and voilations. it should work fine. below is the link:

https://piexpertonline.power.com/site/index

Best Regards