Top254Y-UI-28Vo-1.1A Does not Regulate
See attached PI8 file.
Built exactly to schematic file shown.
Output is low ripple DC, and stable, but not 28V as designed. With 4020 ohm R7/RF3 output is 24.2VDC@zero-load and 19.5V@0.8A load@25 ohms w/470 uF cap. No start up problem at any load. No load switching problems from open load to 25 ohms.
Changing R7/RF3 to 4950 ohms moves DC output to 28.5V@0 load to 22.7V@25 ohm load.
I have 4 working assemblies with identical performance. Need is immediate and urgent.
Please respond with recommendations on how to get 28V output at all loads.
Thank you.
Comments
Your forum does not allow attachments of .uds files. I will reattach the .xls output.
Kindly tell me how to get you the full design file.
thank you.
Here is a .doc file from PIViewer from PIExpert. Why isn't there an easy way to send .uds files?
For the circuit schematic and layouts, just print PDF's from your schematic/layout software.
For the PI Expert file, try making a zip file with your design inside and upload that instead.
-The Traveler
Your forum does not accept zip files. Attached are 2 "pdf" files. So let's play a game:
The TOP254 UI-28-1.0-90%-EF20 NS9.pdf files is a true pdf file generated from a .doc, generated from a .emf, exported from the original .uds file. It includes graphics of the actual layout metal on the 2 sided board. Also included is the .uds file PWB layout and .uds schematic.
The PI8 TOP254 UI-28-1.0-90%-EF20 NS9.pdf file is the original .uds file, which you should be abe to open in PI8 if you rename it.
I'm not able to view/download the attachment you sent me. Can you please send me your schematic, layout, transformer diagram and PI Expert files if they're available?
-The Traveler