Recent content by kaip

Thanks for your reply Brad ! I had replaced the aux diode for a UF4007. The aux voltage reads about 13V Your explanation of the TVS voltage and resulting fault is exactly what happened first time I powered it up. I hadnt placed a 400V TVS but forgot the thing altogether ! Thats why it probably...

Thanks for your reply. Here are some pictures of my prototype. The wire on the bottom is a GND wire for one of the secondary caps. I managed to damage a through plated hole.... The fuse is also missing and it has not been properly cleaned yet :) Now I will check the circuit without the...

Why does this forum resize my images!?

I designed a simple SMPS with a standard transformer: myrra 74050 Up on powering up , it violently blows the fuse and at one time time the AUX supply Electrolytic. Please have a look and help me find whats wrong PCB: Components: Top: Bot: Transformer:

It has been a while. This design is supposed to be simple, almost minimalistic. Mains: 230VAC Out: about 2x50VDC (adjustable, and with other L5 winding could be anything you want) I have some questions about component choice: 1. What is the max current rating I should use for the 12V...

Finally the boards arrived from China. Chinese newyear delayed them by weeks.... I don't have all the components yet but to give you an idea.... Found a small error with one of the blue status LED's on the output. It was the wrong way around. Here is the latest version of the schematic...

I have ordered a few PCBs of my version of the SMPS design. Two sided in PCB green circa 14x12cm. Here is the schematic and PCB: My version is for both 115VAC and 230VAC by use of a jumper. It has an optional feedback loop with an optocoupler. You dont have to use this, but its there. Read...

Progress update....

Here is a version with the EE55 core

Here is my latest version. It is a bit smaller (about 14x12cm) it uses fewer but bigger sized elcos. I will share the gerber files when i have a working prototype. Will also sell the PCBs to fellow enthusiasts.

wally7856: If you just use it without the feedback as in this thread. The transformer (ratio between primary and secundary windings) define your output voltage. There is a calculator for this somewhere on this forum. Output will be about +/- 50V with the transformer material and ratio shown (22...

Thanks. Its my first SMPS. I wanted to start with a known working design and I m happy with all the feedback you guys can give. I used the soldermasks for the pads in the jpeg files. Here are the actual top & bottom in PDF format. (scroll down a bit. Board is about 140x150mms) All clearances...

Here my version. I added some extra options to be able to use regulated as per standard design posted earlier in this thread by MicrosiM. Protection board on PCB. Please check and comment !