Dear Sir,
Refer to the TIDRXG9A.PDF. I have tried to modify the reference model to a 120W-24V-5A power supply.
I'm powered up the unit with 180Vac (Bulk cap 100uF, without PFC).During no-load condition, the output regulation raised up to ~29V.
After powered on, I drew ~0.5A, the regulation down to 24.5V. When I further increase the loading , the output regulation, keep dropping
1A~23.5V 2A~22.9V.. and 3A~22V...4A start to bouncing.
I'm using TSM1014 for secondary sensing and control. Opto-coupler using TCLT1008.
If I tried to add a resistor (20K~100K) across the opto-CE side, the unit can't start-up properly, I guess due to Vcc UVLO.
Shall I share the schematic to you to have a look for helping me to see what's go wrong?
Thanks
BR
Ray
