Hi,
I get a ATX PSU 450W for Repairing one of my customer . But This PSU have all parts OK . I am getting 5V PS-ON and 5VSB . The Power Supply is not running . But this PSU is Running - When I make short Pin 4 of TL494 with GND and this time I do not need to short PS-ON with Ground . Just Short Pin 4 with Ground and PSU is running Fine !!! What is Problem in the Control Section of this PSU ?? What have I to check in the control section ?? This Pin 4 is DTC ( Dead time Control ) of TL494 and it is showing 4.2V .
This Power supply have two IC - TL494 and LM339 .
Waiting for your quick reply ............