power good 0v

[Uniballer]

Re: power good 0v

Isn't pin 6 supposed to be connected to +12V, according to the drawing?

No. 12V is on pin 5.

[LDSisHere]

Re: power good 0v

If the chip you are using matches Everell's drawing, you should trace the circuit for pin 6 to see if there is any faults as you should be getting 12V on that pin when the supply is running. A shorted diode or cap or open resistor in this circuit is most likely the cause of your problem.

[senz_90]

Re: power good 0v

according to pict everell. it is same as my pin connected. but i didn't check carefully on pin 6 connect to. hmm i must checkin again carefully..
but i dont expert on pwm ic work. is there any chance that 12v low on the pin but i am get 12v on yellow rail?
i dont wanna beat anyone cheapie. hahaha.

[LDSisHere]

Re: power good 0v

according to pict everell. it is same as my pin connected. but i didn't check carefully on pin 6 connect to. hmm i must checkin again carefully..
but i dont expert on pwm ic work. is there any chance that 12v low on the pin but i am get 12v on yellow rail?
i dont wanna beat anyone cheapie. hahaha.

The IC is most likely good. The IC has to receive the correct voltage on pin 6 from the supply before it will give a power good voltage on pin 9. Trace the pin 6 circuit, then probe it to see where the voltage stops.

Just make sure you are real careful when you are working with a live supply as it is dangerous. In my work area I have a GFI power outlet for protection in case of an accident or if I do something stupid.

[senz_90]

Re: power good 0v

The IC is most likely good. The IC has to receive the correct voltage on pin 6 from the supply before it will give a power good voltage on pin 9. Trace the pin 6 circuit, then probe it to see where the voltage stops.

Just make sure you are real careful when you are working with a live supply as it is dangerous. In my work area I have a GFI power outlet for protection in case of an accident or if I do something stupid.

yeah. i have checked it. it has connect to 12v rail and pin 14, refer to discaps and resistor nearly pin 6 maybe that is just a voltage drop IMO..don't have a schematic is bad i thought.. i think to make isolation transformer later, i am still to learn deeper.. also i am always using one hand method but i have carefully to do it.. next i am give you the result after have time to check it. it is already midnight here..

[senz_90]

Re: power good 0v

okay. after struggle almost 2 hours. i think that near discaps one, it is no voltage, but didn't caps block dc?
so i just change that ceramic one. and still got no result. i am trying to touch the 5v transformer because it has burn sign on the board after discharge caps. it was warm enough although turn it on for 3minutes (maybe shorted because i am trying to measure the secondary resistance and very low) so i try to measure the primary switch transistor voltage to see if primary side has problem and i makes a bad mistake. slip the probes at the transistor and zappp!! my home MCB down.. i've done likely.. so i just plan to salvages the transient filter or pi filter maybe, primary caps that 680uF (good enough for my psu that has 220uF),maybe the big one transformer, and secondary caps that already changed before, and looks the others that maybe still good to improve my cpu psu that are still running. i get this broken psu from friend for freely, i think this is a good experience for me to learn to be carefull. lol

[domas]

Re: power good 0v

so what did you damage when shortening the transistor? Thermistor, fuse, diode bridge?

[senz_90]

Re: power good 0v

so what did you damage when shortening the transistor? Thermistor, fuse, diode bridge?

i don't check it yet. i just feels done likely so just laying it on my desk. the fuse look likes fine if i am not wrong. maybe the transistor or diode rectifier. when i decides to salvages i would check it. is there any chance to fix it again? i think that would affects a major defective parts..

[LDSisHere]

Re: power good 0v

If you are trying to learn about electronics and repairing stuff the this should be seen as a great learning opportunity. You should try to get it working again, you will learn a lot from the experience even if you do not succeed. I have sabotaged myself, similar to what you did, many times. I was able to learn a lot more than I would have otherwise but that still does not make the experience less frustrating.

[senz_90]

Re: power good 0v

If you are trying to learn about electronics and repairing stuff the this should be seen as a great learning opportunity. You should try to get it working again, you will learn a lot from the experience even if you do not succeed. I have sabotaged myself, similar to what you did, many times. I was able to learn a lot more than I would have otherwise but that still does not make the experience less frustrating.

the first one's that i am thinking about of course learn smps design when asking my friend to give me the PSU. yeah it was give a good learning experience, especially i have to be careful when make a critical measurements. I am not upset even with unsucceed result because that is nobody have a skill and knowledge by instance way. i am learn many thing, but one thing that i am eager to learn is to know what exactly happen each component on circuit and how to calculate the current, frequency, voltage, waveforms, p-p voltage, etc. i am not a student tech like the others that learn many basic things about electrical engineering, so i can't describe anything happened on the complex circuit...

[everell]

Re: power good 0v

I have had some time in the last few days to look at the 2005 chip. I find that the 2005 and 2003 are NOT the same. The schematic for 2003 is correct, but the 2005 uses pin 6 for PG_in and should have a pulsating dc signal varying from zero to about 1.6 volts. The 12 volt overvoltage/undervoltage signal has been moved to pin 1 which now has a double function. Pin 1 is also used for Vcc. Before power is applied, pin 1 should have 5 volts from the 5vsb. When power supply is turned on (shorting green wire to black wire) the voltage should increase to 12 volts.

Since you have decided to scrap this power supply, I suppose I am too late with this information. I don't know of any data sheets available for the 2005 pwm chip, so if there is any interest I suppose I could start a thread showing schematics of the chip of the year series: 2002/2003/2005/2008/2012. There might be some chips with other year marking, perhaps 2004. I have not seen a 2004 chip.

[senz_90]

Re: power good 0v

I have had some time in the last few days to look at the 2005 chip. I find that the 2005 and 2003 are NOT the same. The schematic for 2003 is correct, but the 2005 uses pin 6 for PG_in and should have a pulsating dc signal varying from zero to about 1.6 volts. The 12 volt overvoltage/undervoltage signal has been moved to pin 1 which now has a double function. Pin 1 is also used for Vcc. Before power is applied, pin 1 should have 5 volts from the 5vsb. When power supply is turned on (shorting green wire to black wire) the voltage should increase to 12 volts.

Since you have decided to scrap this power supply, I suppose I am too late with this information. I don't know of any data sheets available for the 2005 pwm chip, so if there is any interest I suppose I could start a thread showing schematics of the chip of the year series: 2002/2003/2005/2008/2012. There might be some chips with other year marking, perhaps 2004. I have not seen a 2004 chip.

Yes. I have look some site, I just have datasheet about 2005 IC if I correctly remembered. 2003 shcematic and 2005 pins is looks different as I think. That's would be a good thread, you have to post it so anyone could learn it please
Unfortunately, this PSU is scrapped already but I would like to learn because I have the other same one PSU to fix if this PSU failed further.
I have this datasheet that one of them I get from this forum.

[Escort Eagle]

Re: power good 0v

AT2005 and ATX2005 PIN configuration are not same . So, you can not use them as substitute . Currently I am working with LPG899 and CG8010 Controller . Both IC's PIN Configuration and Circuit design are same . But still they do not work with each other . Previously I worked with SD6109 and HS8108 . Their PIN configuration was same but they did not work at all .

[senz_90]

Re: power good 0v

AT2005 and ATX2005 PIN configuration are not same . So, you can not use them as substitute . Currently I am working with LPG899 and CG8010 Controller . Both IC's PIN Configuration and Circuit design are same . But still they do not work with each other . Previously I worked with SD6109 and HS8108 . Their PIN configuration was same but they did not work at all .

I am not comparing it yet because when I get this ATX2005 IC datasheet my PSU already scrapped, but you give a good clues.

[placidocd]

Re: power good 0v

Back to topic, no power good.
I'm still confused with my 0v power good, so I decide to give power good directly from 5v rail (red wire), and the mainboard can work normaly, runnig for a week and still working properly .

[placidocd]

Re: power good 0v

But not all motherboard can live normaly with this PSU, some only blinking on 'power on led' indicator, but doesn't kill mobo or else.