Transistor J13009-2 equivalent to the E13009-2 ? (stuttering ATX PSU repair)  - Page 1
Forum section: electronics / beginners

author: Rita Graça
author_rank: Contributor
timestamp: July 16, 2023, 04:01:48 pm
content: Hello everybody.I have an ATX PSU that has a couple of J13009-2 transistors doing the switching. Both J13009-2 were not working, so I replaced them with two E13009-2.Now, I have 5V stand by, but no other voltage rails (3.3V, 5V and 12V).I am trying to find out if the J13009-2 is equivalent to the E13009-2 (the E13009-2 was suggested by an electronics shop). I searched the general web and EEVblog forum too. On alltransistors.com I could not really find any info about the equivalence.Where can I check this?Please excuse if my English is not the best.Cheers.

author: Vovk_Z
author_rank: Super Contributor
timestamp: July 17, 2023, 06:40:40 am
content: I guess any 13009 should do, so that's not a consern.If those large transistors failed (were shorted) then it often occurs together with small elements near them. Look at small (or not) resistors or diodes which led to bases or emitters of those transistors. Some of them possibly are broken too.C945 (a pair) could die too. You may replace them.And it's good to check a control signal at IC outputs if there is some signal (if you have an oscilloscope).Most often IC is fine and you just have to replace 2-4 resistors and 2x C945.Look at some typical schematics with 13009 and your IC. I mean google something like "ATX PS 13009 TL494 schematics" ('Images') (replace 'TL494' with your PWM IC.

author: liaifat85
author_rank: Regular Contributor
timestamp: July 17, 2023, 11:09:11 am
content: The suffix at the beginning depends on the manufacturer. All 13009 behave the same. You can choose any.

author: Rita Graça
author_rank: Contributor
timestamp: July 30, 2023, 12:55:21 am
content: Hi Vovk.Thank you for your suggestions. I checked all the components connected to the switching transistors and found 2 tiny resistors, 1 opened and the other with much more value than the stripes. One of them was actually burned, but it was so little that I could not see it, initially. The resistors were very small, but though hole, not SMD.I replaced those transistors, and now the PSU seems to want to start: the fan moves a bit and then stops, and the voltage rails raise their values and then drop to zero.Here is a video of the behaviour (22s):https://youtu.be/zbyX2FLWaz0If you turn the volume all the way up, you will hear a clicking sound whenever the fan moves.

author: Rita Graça
author_rank: Contributor
timestamp: July 30, 2023, 12:56:15 am
content: liaifat, thanks for clarifying the prefix issue.

author: Vovk_Z
author_rank: Super Contributor
timestamp: July 30, 2023, 02:22:46 am
content: Start and then immediate stop usually mean short circuit somewhere at the output. Mostly that's one of Shottky diodes are dead.You have to check every semiconductor before a start.

author: Rita Graça
author_rank: Contributor
timestamp: August 01, 2023, 11:33:29 pm
content: Hi Vovk,I removed and tested all the diodes on the secondary sector of the PSU, all of them are ok.The main caps on the primary are two 560uF. They measure around 440uF each. But I would think that would not be a problem when the PSU is running unloaded...

author: wraper
author_rank: Unknown
timestamp: August 01, 2023, 11:37:43 pm
content: Check small electrolytic capacitors on their bases.

author: Vovk_Z
author_rank: Super Contributor
timestamp: August 02, 2023, 10:38:10 pm
content: Quote from: Rita Graça on August 01, 2023, 11:33:29 pmThat's typical for the cheap noname power supply. Yes, that's ok, it'll work fine until you load it too much. Just don't expect to have all watts from it, e.g. if it's 500 W 'rated' then it really has 350-400 W rated power. If you have 13009 there then it's real rated power is not larger then 300-350 W. And 440 uF main capacitors are ok for 300-350 W power supply.Upd.: that's good sign when they are almost equal capacitance. If difference is more then 5-10% between them - that's not good.

author: Rita Graça
author_rank: Contributor
timestamp: August 04, 2023, 10:26:59 pm
content: Checked all the electrolitic caps on the secondary. They all had a capacitance above the specification.I reckon I will start checking the resistors now...

author: Vovk_Z
author_rank: Super Contributor
timestamp: August 05, 2023, 12:37:43 pm
content: I bet resistors are fine. It could be a voltage control IS shuts down main power supply or something similar..

author: Rita Graça
author_rank: Contributor
timestamp: August 05, 2023, 03:29:49 pm
content: Quote from: Vovk_Z on August 05, 2023, 12:37:43 pmDo you mean the PWM chip?The one on this PSU is the HS8108. I took a look at the datasheet, but I don't quite understand where the output of the square wave is. I do not have an oscilloscope, so I don't quite know how to test it.

author: Vovk_Z
author_rank: Super Contributor
timestamp: August 06, 2023, 11:06:01 am
content: I mean 'Power good' control. Seems this IC have it all integrated: both PWM (voltage regulation) and voltage contror and protections.IDK what you can do without an oscilloscope to check this IC. You may only check it has a power.Have you replaced C945?

author: MathWizard
author_rank: Super Contributor
timestamp: August 06, 2023, 11:50:36 pm
content: Most computer PSU's I've seen will have a controller chip for the primary side auxiliary low voltage, ~12-15V, and that also makes 5V standby on the output side through a "transformer". That chip can sense some problems and shut down.Then there's the main PWM and usually PFC controller, that chip monitors a few things, and and shut down the PSU too.Then on the output side, there's a supervisor chip, and that can sense a few things too, like under voltage, overvoltage, over current, and or over power, over temperature is usually done only by that chip as well.Then there might be another buck converter making 3.3V and 5V from 12V, and that chip could have a problem and tell the PWM/PFC chip to shut down.If you have an oscilloscope, (ok you don't tho)have a look around at what the output rails get to, and if possible look at the reset and/or power good signal pins on those chips.If 1 chip shut down the PSU, the other chips would probably see the undervoltage happening, so you'd probably want to see which one does it 1st.I'd start with the aux/5V stby controller, then the PWM/PFC then output controllers. ith a DMM you might still still if the outputs get to the correct DC values. Yeah I never tried working on 1 of these without a scope tho. Myself, I mapped out the whole circuit of a few now, and made models in LTSpice. There's not really that much to them, but it can be quite a tangle to map out.

author: Rita Graça
author_rank: Contributor
timestamp: August 07, 2023, 03:09:55 am
content: Quote from: Vovk_Z on August 06, 2023, 11:06:01 amIs the C945 a transistor?I found an STC945 transistor on the primary side. I tested it using the diode function of the DMM. I found 2 diode junctions: from base-emitter and base-collector. From emitter-base and collector-base I got "OL". So, I think it is ok.I tested all the transistors on the secondary, and those seem ok.And I agree, this is an one-in-all chip, according to the datasheet:https://www.rom.by/files/hs8108.pdfMy DMM has a frequency\duty cycle function. Maybe that could be used to test the PWM output?

author: Rita Graça
author_rank: Contributor
timestamp: August 07, 2023, 03:16:26 am
content: Quote from: MathWizard on August 06, 2023, 11:50:36 pmHi MathWizar.Thank you for your suggestions. This PSU is rather simplistic, it does not have a PFC (it has the connector for it, but it is jumpered).There is only an one-in-all chip on the secondary. Here is the datasheet:https://www.rom.by/files/hs8108.pdfIt controls PWM, voltage sense (3.3V rail), OVP, OCP.

author: Vovk_Z
author_rank: Super Contributor
timestamp: August 07, 2023, 03:01:53 pm
content: Quote from: Rita Graça on August 07, 2023, 03:09:55 am

author: Rita Graça
author_rank: Contributor
timestamp: August 07, 2023, 09:21:08 pm
content: QuoteThe STC945 has a drop of 0.707V between the base and the emitter. And it has a drop of 0.704V between the base and the collector. I reckon it is good?

author: Vovk_Z
author_rank: Super Contributor
timestamp: August 07, 2023, 09:49:49 pm
content: Yes, >=0.700 mV looks like fine, but still there is a small possibility their properties could degrade.