Question; does anybody know the type & value of the little red diode above D22 in the picture? I accidently broke it when removing all the white goo
Hi Pjotrovic! It's just a signal diode with IN4148 mark on it.Question; does anybody know the type & value of the little red diode above D22 in the picture? I accidently broke it when removing all the white goo
Peter
hello guys,
sorry for digging this thread, but i could do with some advice.
I am re-purposing a sub and i want to keep the PSU (the same this thread is about) but will get rid of the amp/DSP part. I figured out how to make the PSU work stand alone:
Just need to bypass transistor Q1, so that Q2 becomes conductive and supplies 12V to the PWM control IC. This is equivalent to supply 4.6V to the trigger input pin STB.
However, this is not sufficient for the PSU to work. It is necessary to connect +7V pin to -7V pin with a resistance no more than 2K in between. I don't know much about electronics and i don't understand why this is necessary, but it is. It is as if it is necessary to draw some current out of the 7V lines so that the auxiliar PSU can supply the 12V. As you approach to 2kOhm, the PSU starts to act erratically and the voltage output of the main PSU starts to decrease, and the lower the resistance the better it works, but i am afraid to go too low.
My question for you guys, how would you chose the right resistance value?
I understand that this part of the circuit is there only to supply the DSP board and supply 12VDC to the main PSU, so maybe it doesn't really matter and as soon as the main output reaches its maximum and the PSU stops to act erratically all is good, but i would like to hear the opinion of someone who understands how this works.
Thanks a lot for your comments and suggestions.
sorry for digging this thread, but i could do with some advice.
I am re-purposing a sub and i want to keep the PSU (the same this thread is about) but will get rid of the amp/DSP part. I figured out how to make the PSU work stand alone:
Just need to bypass transistor Q1, so that Q2 becomes conductive and supplies 12V to the PWM control IC. This is equivalent to supply 4.6V to the trigger input pin STB.
However, this is not sufficient for the PSU to work. It is necessary to connect +7V pin to -7V pin with a resistance no more than 2K in between. I don't know much about electronics and i don't understand why this is necessary, but it is. It is as if it is necessary to draw some current out of the 7V lines so that the auxiliar PSU can supply the 12V. As you approach to 2kOhm, the PSU starts to act erratically and the voltage output of the main PSU starts to decrease, and the lower the resistance the better it works, but i am afraid to go too low.
My question for you guys, how would you chose the right resistance value?
I understand that this part of the circuit is there only to supply the DSP board and supply 12VDC to the main PSU, so maybe it doesn't really matter and as soon as the main output reaches its maximum and the PSU stops to act erratically all is good, but i would like to hear the opinion of someone who understands how this works.
Thanks a lot for your comments and suggestions.
Hi, sorry if I'm bumping an old thread, but it's been a bit frustrating trying to fix this HYS3C300 PS. Granted, it is probably due to my mistake/inexperience when initially testing the board. I'll try my best to be brief.
A month or so ago, my Sunfire SDS8 subwoofer stopped working, it wouldn't power up at all. I opened it up and inspected it visually, found no issues. Doing a bit of googling, I couldn't find much info about it because I was searching using the sub model number. So I figured I might try replacing a few capacitors, as I bought the sub used and have no idea how much abuse it has endured over the years. Got the parts on that week and before I started any work, I thought it might be a good idea to check what voltages I had on the +7V and -7V pins, and the ones beside it that have no label.
In this test is where I think I made a huge mistake, I disconnected the amp board and turned on the power supply by itself. After a few seconds I heard a loud pop so I turned it off immediately. I've repaired other electronics before but they were simpler, I guess... So it didn't seem like it would be an issue to turn on the PS like this. After inspection, I noticed resistors R19, R21 and R22 (close to the IC mentioned in the OP) were damaged, and I couldn't read the numbers on them. This led me to google again, and after a while I stumbled on this thread, where I found a lot of great info, wish I had found this sooner.
After reading this thread, I ordered new resistors, the WS3252 IC to replace the original mentioned in the OP, and a few SB 260 diodes in case D1 or D2 was faulty, as mentioned by tonebells. So last Saturday I worked on it. First I removed both D1 and D2. D1 seemed ok, but given that I had a new one, figured I might as well replace it. D2 seemed faulty, I was getting 0 Volts on the meter in diode mode in either direction, whereas D1 would show 0.2 when conducting and nothing when reversing polarity. It was an SB160, but I replaced it with an SB 260, seems to have the same characteristics, just supports higher current.
Aftewards, replaced a few caps around that area and inspected IC 32D06 again. I was hoping to not replace it as the thing is tiny, and my eyesight is not what it used to be, but I noticed it looked like it was broken, the cap seemed to be coming off. Well, had no choice but to do it, at least I had the sense of figuring out the orientation in which to put the new chip. Found which pin was connected to ground, then looked at the WS3252 datasheet, noticed that pin 1 needs to be on gnd, placed it accordingly on the board. Checked for any bridges between the pins, and if each one had connection to the nearby components, everything looked to be correct.
Finally, it was time to test it, I connected everything this time, before turning it on, but unfortunately, once I did it, I had another pop again, and the same resistors went kaputz. Disheartened, I disconnected everything, put it all away and have been pondering what to do next.
I feel like I mucked up the board beyond repair and should just give up on it. On the other hand, feels like such a waste to get rid of a decent sub just because of this faulty board. I googled around to try and find a replacement for it, but no luck so far.
Anyway, thanks for reading, I feel better already just putting this out there, but I'd appreciate it if anyone could provide some advice.
A month or so ago, my Sunfire SDS8 subwoofer stopped working, it wouldn't power up at all. I opened it up and inspected it visually, found no issues. Doing a bit of googling, I couldn't find much info about it because I was searching using the sub model number. So I figured I might try replacing a few capacitors, as I bought the sub used and have no idea how much abuse it has endured over the years. Got the parts on that week and before I started any work, I thought it might be a good idea to check what voltages I had on the +7V and -7V pins, and the ones beside it that have no label.
In this test is where I think I made a huge mistake, I disconnected the amp board and turned on the power supply by itself. After a few seconds I heard a loud pop so I turned it off immediately. I've repaired other electronics before but they were simpler, I guess... So it didn't seem like it would be an issue to turn on the PS like this. After inspection, I noticed resistors R19, R21 and R22 (close to the IC mentioned in the OP) were damaged, and I couldn't read the numbers on them. This led me to google again, and after a while I stumbled on this thread, where I found a lot of great info, wish I had found this sooner.
After reading this thread, I ordered new resistors, the WS3252 IC to replace the original mentioned in the OP, and a few SB 260 diodes in case D1 or D2 was faulty, as mentioned by tonebells. So last Saturday I worked on it. First I removed both D1 and D2. D1 seemed ok, but given that I had a new one, figured I might as well replace it. D2 seemed faulty, I was getting 0 Volts on the meter in diode mode in either direction, whereas D1 would show 0.2 when conducting and nothing when reversing polarity. It was an SB160, but I replaced it with an SB 260, seems to have the same characteristics, just supports higher current.
Aftewards, replaced a few caps around that area and inspected IC 32D06 again. I was hoping to not replace it as the thing is tiny, and my eyesight is not what it used to be, but I noticed it looked like it was broken, the cap seemed to be coming off. Well, had no choice but to do it, at least I had the sense of figuring out the orientation in which to put the new chip. Found which pin was connected to ground, then looked at the WS3252 datasheet, noticed that pin 1 needs to be on gnd, placed it accordingly on the board. Checked for any bridges between the pins, and if each one had connection to the nearby components, everything looked to be correct.
Finally, it was time to test it, I connected everything this time, before turning it on, but unfortunately, once I did it, I had another pop again, and the same resistors went kaputz. Disheartened, I disconnected everything, put it all away and have been pondering what to do next.
I feel like I mucked up the board beyond repair and should just give up on it. On the other hand, feels like such a waste to get rid of a decent sub just because of this faulty board. I googled around to try and find a replacement for it, but no luck so far.
Anyway, thanks for reading, I feel better already just putting this out there, but I'd appreciate it if anyone could provide some advice.
Reading the thread again, seems I somehow missed that the problem reported by user kib3 is the same as I had, a few blown resistors. Too bad he didn't mention which diode he referred to, but I assume it must be either D1 or D2, which I already replaced. But in his case he had to replace the CS1N60 mosfet as well, something which I did not check, because visually mine seems ok.
So, yesterday, after work, I had a quick look at it, and it seems the one on my board is shorted. Tomorrow I'll desolder it from the board and test it again, if it is bad, then it is likely to be the cause of my previous incident. The annoying part is that getting a replacement will take forever, postal service here is horrendously slow. But I'll report back once I manage to replace it, hopefully I can get this working again.
So, yesterday, after work, I had a quick look at it, and it seems the one on my board is shorted. Tomorrow I'll desolder it from the board and test it again, if it is bad, then it is likely to be the cause of my previous incident. The annoying part is that getting a replacement will take forever, postal service here is horrendously slow. But I'll report back once I manage to replace it, hopefully I can get this working again.