This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

LM25574 inverting does not work

Other Parts Discussed in Thread: LM25574

We have done the WEBBENCH Simulation using an LM25574 to generate +15V from a +15V supply.

The current we need is about 20 to 50mA. We have to supply two opamps.

I have included the WEBBench Desing and the screenshots from my CAD. I can not see the problem and i need to get this pcb working. The +15V is the only part of the circuit which is not working. I did not expect this to be so hard to achieve a negative voltage.

We have a stable 15V but at the output we can only see a small positive voltage of about 1V with the opamps connected. Without the two opamps the voltage drops even further.

Please help me on this issue and tell me where i have gone wrong.

Best regards

3324.WEBENCH® Design Report - WebenchReportsServlet.pdf

Bottom Layer

Midlayer 1

Midlayer2

Powerplane GND

Powerplane VCC

Toplayer