Oh great bro. You need that chip to make audio signal. Install this chip and new mosfets. Hope your amp will be running.
So heres the update.
Nothing changed. SMH...
So ive changed the 2092 chip, the 494 chip, The bulged main rail caps, new mosfets and nothing has changed.
I think my problem is just a small component that I am probably over looking, but I cannot find it for the life of me.
I do have my cheesy oscilloscope, now, so I can kind of see what the amp is doing a little better.
With the output fets out of the board, and 2 power supply fets (one in each bank), once the rail voltage starts to build, and hits about 48-50volts the amp shuts down (protect mode I assume). So I have to assume there is a short or a failed component somewhere but I just cant find it. I guess im just a dummy lol.
Another thing the amp is doing is when I power it on and I probe the out put terminals, its generating a sudden spikes, (Which is what Im assuming is the cracking pop noises Im hearing in the speaker when I hook up the speaker)
Nothing changed. SMH...
So ive changed the 2092 chip, the 494 chip, The bulged main rail caps, new mosfets and nothing has changed.
I think my problem is just a small component that I am probably over looking, but I cannot find it for the life of me.
I do have my cheesy oscilloscope, now, so I can kind of see what the amp is doing a little better.
With the output fets out of the board, and 2 power supply fets (one in each bank), once the rail voltage starts to build, and hits about 48-50volts the amp shuts down (protect mode I assume). So I have to assume there is a short or a failed component somewhere but I just cant find it. I guess im just a dummy lol.
Another thing the amp is doing is when I power it on and I probe the out put terminals, its generating a sudden spikes, (Which is what Im assuming is the cracking pop noises Im hearing in the speaker when I hook up the speaker)
I have been doing some more investigating, and I have probed all the voltages on all the IRS2092 chip, and when I first turn the amp on, all my voltages on the pins look ok (from what I can tell), but on quite a few of the pins, the voltages start to slowly drop, and then the amp goes into protect mode and shuts itself off.
So im thinking something is making the voltages on the 2092 chip drop, and I was wondering if anyone has any idea what would cause that? (A bad diode?)
The 2092 is the chip responsible for protect mode correct?
I also probed the 494 chip, and all its voltages seem pretty stable, and im getting a pwm wave from the 494 chip, so i am pretty sure my problem is coming from somewhere in the 2092 circuit.
Here are the voltages I found on the 2092 if anyone cares to weigh in, Any help is appreciated.
So im thinking something is making the voltages on the 2092 chip drop, and I was wondering if anyone has any idea what would cause that? (A bad diode?)
The 2092 is the chip responsible for protect mode correct?
I also probed the 494 chip, and all its voltages seem pretty stable, and im getting a pwm wave from the 494 chip, so i am pretty sure my problem is coming from somewhere in the 2092 circuit.
Here are the voltages I found on the 2092 if anyone cares to weigh in, Any help is appreciated.
There are also various things that you can check.
1. Check the output inductor, capacitor and resistances at the output speaker terminal, if anyone of these short it can also protect the amplifier.
2. Basically three types of protections in the amplifiers. Short,thermal and dc protection. Check all of these. A thermistor can also protect the amp if shorted .
3. In the audio section put 1 mosfets each for low and high side after checking the inductor.
Hope you will find the fault this time.
Remove the inductor from pcb to check. I have repaired some amps with enamel from copper winding rubbing of after vibration.
1. Check the output inductor, capacitor and resistances at the output speaker terminal, if anyone of these short it can also protect the amplifier.
2. Basically three types of protections in the amplifiers. Short,thermal and dc protection. Check all of these. A thermistor can also protect the amp if shorted .
3. In the audio section put 1 mosfets each for low and high side after checking the inductor.
Hope you will find the fault this time.
Remove the inductor from pcb to check. I have repaired some amps with enamel from copper winding rubbing of after vibration.
I checked output inductors, they seem fine, and they test ok.
Will put another output mosfet in each bank and see what happens.
I think there may be some DC getting to the speaker terminals somehow, cause it would cause the speaker to make weird popping noises no? Also it would put the amp into protect right?
What are some things that could cause DC to end up at the speaker terminal side?
Will put another output mosfet in each bank and see what happens.
I think there may be some DC getting to the speaker terminals somehow, cause it would cause the speaker to make weird popping noises no? Also it would put the amp into protect right?
What are some things that could cause DC to end up at the speaker terminal side?
Yeah I put everything back together, and I AM getting intermittent DC bursts on the speaker terminals.
Those were the cracking sounds I was hearing on the speaker.
Now I just need to figure out what is causing it.
I have no idea what would cause that.
Those were the cracking sounds I was hearing on the speaker.
Now I just need to figure out what is causing it.
I have no idea what would cause that.
Check your op amp volatges.
It can also cause by damaged potentiometers. Clean all the switches properly or if you can change them. Getting Dc on spkrs can be caused by inductor, short mosfets, any of the side from low and high is not working. If only one side working it can also cause this. Check low side and high side gates. Check outputs from your driver 2092s LO and HO. Check all the voltage regulators ( 7805,7815,7915, ) Their input and output.
It can also cause by damaged potentiometers. Clean all the switches properly or if you can change them. Getting Dc on spkrs can be caused by inductor, short mosfets, any of the side from low and high is not working. If only one side working it can also cause this. Check low side and high side gates. Check outputs from your driver 2092s LO and HO. Check all the voltage regulators ( 7805,7815,7915, ) Their input and output.
I went to check my op amps, and gave them a diode test, looked at them, and decided to look at them with the oscilloscope to see what they looked like powered on, and the amp just started working. I have literally ZERO idea why, but it is working at the moment...
all the fets seemed to be nice and cool, a slight warmth, but not hot, and there was only one in each bank. The drive signals looked good on the scope..
Im gonna let it set over night, and see if its still working tomorrow, and if it is, put the rest of the fets in and see what happens.
Kinda sucks, because I dont really trust it, and am nervous to put it in my car if it keeps working. Idk. We'll see tomorrow I guess.
all the fets seemed to be nice and cool, a slight warmth, but not hot, and there was only one in each bank. The drive signals looked good on the scope..
Im gonna let it set over night, and see if its still working tomorrow, and if it is, put the rest of the fets in and see what happens.
Kinda sucks, because I dont really trust it, and am nervous to put it in my car if it keeps working. Idk. We'll see tomorrow I guess.
Yes bro. May be some solder is missing. Desolder if you find any type of dry solder with soldering paste applying on it. Hope it will work.
Yeah Idk, I put all the rest of the fets in and gave it a bit of a "stress test" and it seems to be working fine now. I guess that will teach me to be a little more methodical and test a little more often to find out when I have changes in operation.
I put some solder mask on the spot that had some bare traces and went over a few spots with solder, but to be honest every spot looked good, and I went over each solder joint with my little microscope about 3 times.. And glued my output inductors back down.
All back together now, and gonna throw it in my car and just see what happens ha. If she blows up, im just gonna use this thing for parts in the future ha. Just hope it doesnt take my subs with it haha.
Thanks bobthemechanic for all your help man. I appreciate it big time
I put some solder mask on the spot that had some bare traces and went over a few spots with solder, but to be honest every spot looked good, and I went over each solder joint with my little microscope about 3 times.. And glued my output inductors back down.
All back together now, and gonna throw it in my car and just see what happens ha. If she blows up, im just gonna use this thing for parts in the future ha. Just hope it doesnt take my subs with it haha.
Thanks bobthemechanic for all your help man. I appreciate it big time
Ok bro. No problem. Hope it will work .
This is also some kind of new experience for me. I repaired so many amps in last 15 years. I do it these kind of stuff on daily basis. But this conversation is different, because repairing amps on my bench is more easily bcz i have all the things infront of me but helping you on text is also great.
This is also some kind of new experience for me. I repaired so many amps in last 15 years. I do it these kind of stuff on daily basis. But this conversation is different, because repairing amps on my bench is more easily bcz i have all the things infront of me but helping you on text is also great.