DPA425GN Problem

Posted by: ssshamil on 07/22/2015

Hi;

I am working on a design, schematic is attached. I have a problem.

When i power the circuit with no load, otutputs are ok (+12V and -12V).

But when i connect just a small load for 1mA or 5mA current, output voltage is goning down. Oscillating near 5 volts.

For example with 100mA load, voltage oscillating near 1 - 2 volts.

I checked all my PCB routes, component values etc.

I am using PI expert for two years, and i have experiences with TOP255GN and TOP family.

But this is my first project with DPA family.

Please HELP.

Best regards.

Files

DPA425GN.JPG (46.1 KB)

Comments

is there anyone using DPA425GN or DPA family products?

Hi,

Can you please verify the transformer to see if it has been wounded according to the specification or there is a polarity reversal?

Could you please attach your transformer construction document and PCB layout?

Regards,

PI-NANO

Files attached. I tried with 3 transformers against it can be wounded.

Best regards.

Attachment	Size
EFD20-TRC-SMPS-Trafo.pdf (65.94 KB)	65.94 KB
DPA425_PCB.JPG (103.71 KB)	103.71 KB

Hi,

PCB layout refernce designators are not matching with schematic.

Could you please attach correct PCB layout which matches with the schematic.

Regards,

PI-NANO