Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Register Log in

switching power supply with lnk304

Status
Not open for further replies.
E

electronicsIUST

Member level 3
Joined
Feb 12, 2017
Messages
67
Helped
0
Reputation
0
Reaction score
0
Trophy points
6
Activity points
575
Hi, I use below circuit to build 12Volt 100-200mA from 220V AC with lnk304. But the problem that I have encountered is that some of these circuits explode after a while. But some of them are still working for 3-4 months. What can be the reason for this problem?!

12volt.PNG
 

betwixt said:
Could be for many reasons but first tell us what you have connected to the 12V outut please.

Brian.
Click to expand...

It is connected to two relays and also to input of a LM1117 in order to create 3.3 Volt.
 

...and what part explodes?

You have no over voltage protection or EMC filtering on the AC input so it might be prone to to interference spikes. The other danger is that something connected to the output can sink current to ground because there is no voltaic isolation.

Brian.
 

betwixt said:
...and what part explodes?

You have no over voltage protection or EMC filtering on the AC input so it might be prone to to interference spikes. The other danger is that something connected to the output can sink current to ground because there is no voltaic isolation.

Brian.
Click to expand...

Thanks for your reply,
Usually the input of circuit and before lnk304 and also NTC explode. Also it seems that Phase and Null become short circuit because arc occurs and main fuse of home activates.
What can resolve this problem?!
 

Hi,

please post the PCB layout of your circuit... so we are able to verify this against the datasheet.
Also post the manufacturer and exact names of the used parts.

Klaus
 

also, you shoudl be careful you have used fast enough diodes. What diodes have you used.
Also, you have half wave rectifiaction.....so your lnk304 could be switching on/off/on...which mightbnt do it any good
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top