I have designed a 12.2V, 9.4A fly-back power supply using the PI Expert Suite.
I have attached the design file and circuit diagram below.
1. Output voltage drops to 7.9-8V when drawing more than 3A
2. It is unable to supply more than 4.4A of current
1. No load voltage is 12.2V as designed
2. Output voltage drops to 11.8V under 1A load
3. Output voltage drops to 11V under 2A load
4. Heat-sink attached to TOP259EN is warm to touch
5. Heat-sink attached to Output Rectifier is very hot
Both heat-sinks are of the same size: 20mmX60mm of 2mm thick Aluminum strip
The transformer was not made by us but one sample was opened and verified to be matching with the specifications provided by the suite, with one exception. The terminations for the foil winding were done using a single wire as opposed to 2 wires suggested by the designer.
Output capacitor bank is made up of 4X 1000uF Low ESR capacitors instead of 4X 47uF as suggested by the designer.
What would be the best method to use the remote ON/OFF function? Currently we have connected an opto-coupler output between the X pin and High Voltage Negative and controlling it via a daughter board. The supply was also tested by connecting the X pin to High Voltage Negative to rule out malfunction because of remote ON/OFF, but it still functioned as described above.