Hi,
I need a Repair/Service Manual for ATX Power Supply . It will be more helpful if it is a diagram based on Made by China ATX Power supply . Because in my country - China made ATX Power Supply is available .
If anyone have this, please share with me ..........
I´m aware that is not the answer you expect, but most of problems related to power supplies are statistically concentrated in switching devices ( IGBT, MOSFET ) or at the Fuse.
Thanks Andre for your Reply . Yes you are right . I am facing Switching problem with an ATX PSU . This PSU has burnt out 13007 Transistor and its Base fusing Resistor 10 ohms . I have Replaced them but still it is not starting . I have checked rest all of parts of the PSU Except in Controller section's Resistors . But in Controller section - I am getting 5VSB and 5V PS-ON . But still it does not run . Even I have changed IC TL494 and LM339 also ...... but all the hail ..... It does not listen to me at all . What will I do now ??? Why it is not switching ???
What about the ''+12V" power supply from the stand-by circuit (usually for a value of 15-25V), to be applied for the driver section, did you measure it? Any voltages on TL494 pinouts?
I have checked Q4 and Q5 C945 - Both of them are Fine . C9/C10 are 2.2μF/50V - this capacitors seems to be OK . Will I change it though ?? There is no R7 and R11 Resistor . They have only one fusing Resistor 10Ω Which is in Transistor's Base R6 and R10 . But they have used two signal/Crystal Diode in place of one Diode . They are D3/D4 and D5/D6 . I have checked them . They are OK . Still Do I need to change these 10Ω Resistor and D3/D4 and D5/D6 Crystal Diode (1N4148) ??
And yes you are right . PS-ON voltage seems to be low . I measured the voltage and it is 4.8V . But there is no Capacitor with the PS-ON nor any Transistor . Will 4.8V be problem for PS-ON ?? How can I increase the voltage of PS-ON to 5V ??
And one thing we need give attention in the previous Post . That is DTC (Dead Time Control) Voltage of Pin4of TL494 . As it's Datasheet DTC will be 3.3V (Maximum) at Zero Duty Cycle . And OV at Max. Duty Cycle . Here it is showing 3.2V . Is Zero duty Cycle means PS-OFF Condition ??
Wow. lots of SMPS circuits here, but I want to have a circuit diagram of bit higher wattage PSUs, i.e. >= 500W - 1000W. Want to have circuits of dual rail system with almost 40-44A on +12V line. Can anybody have those circuits?