Hey! I've been working on this amp for awhile and at first I thought it was the IRS 2093M that was the issue, given the fact the the fan stopped working, so I thought the chip cooked itself.
Bought the chip on Digikey dropped it in same issue. Also there's this periodical pop sound when speakers are hooked up and you can just barely hear the audio prior to me changing out the chip. But I don't think there was voltage on the output before, there no 4.9 volts sitting on the output, so I took out the entire output stage, almost. Now there isn't any voltage.
Can anyone help?
Power supply is okay 53- and 53+ on the rails. There's also 14+ and 14- on the op-amps and the IRS 2093 chip also has its 2 14 volts supply and 5- and 5+ volts.
Bought the chip on Digikey dropped it in same issue. Also there's this periodical pop sound when speakers are hooked up and you can just barely hear the audio prior to me changing out the chip. But I don't think there was voltage on the output before, there no 4.9 volts sitting on the output, so I took out the entire output stage, almost. Now there isn't any voltage.
Can anyone help?
Power supply is okay 53- and 53+ on the rails. There's also 14+ and 14- on the op-amps and the IRS 2093 chip also has its 2 14 volts supply and 5- and 5+ volts.
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Are you testing with all of the components currently in the board?
Do you have audio reaching the IC?
CSD voltage on pin 48? (black probe on the -5v pin, pin 42)
Do you have audio reaching the IC?
CSD voltage on pin 48? (black probe on the -5v pin, pin 42)
Yes, i did do the initial testing with everything on the board and also with the factory IC installed. I thought it was the IC so i bought 2 from Digikey and installed one. then i noticed i'm seeing the gate drive voltage on the output.
The CSD voltage keeps fluctuating it goes up to about 2-3 volts then drops back down to -1-2 volts and it just keeps doing that. I put the black probe on the negative rail voltage to test, but not on VSS (pin 42) is it specific? I also checked for VCC and VCC2 both are there and they're 14 volts.
With the first IC in from factory signal was coming into the chip, you could even hear some audiobut it was low crackling. and while probing the gate drive on the high side i would see a pulse like the IC was trying to oscillate and i would hear a pop in the speaker.
Also the diodes and resistors that produce the +5 and -5 volts are pretty hot, could there be a short there or something?
The CSD voltage keeps fluctuating it goes up to about 2-3 volts then drops back down to -1-2 volts and it just keeps doing that. I put the black probe on the negative rail voltage to test, but not on VSS (pin 42) is it specific? I also checked for VCC and VCC2 both are there and they're 14 volts.
With the first IC in from factory signal was coming into the chip, you could even hear some audiobut it was low crackling. and while probing the gate drive on the high side i would see a pulse like the IC was trying to oscillate and i would hear a pop in the speaker.
Also the diodes and resistors that produce the +5 and -5 volts are pretty hot, could there be a short there or something?
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The CSD voltage must be measured with the correct reverence. That's pin 42.
Please explain:
then i noticed i'm seeing the gate drive voltage on the output.
^^^ Are you saying that you're getting drive pulses to the output FET gates with no output FETs in the circuit?
Please explain:
then i noticed i'm seeing the gate drive voltage on the output.
^^^ Are you saying that you're getting drive pulses to the output FET gates with no output FETs in the circuit?
Okay, I'm going to solder in the old IC and measure from that point. But what then if it's the same thing?
Meaning, when the amp is on, I'm seeing 4.9 volts, which is the same voltage on the gate. High side gate pin and low side drain pin has 4.9 volts but no oscillation.
Even with no FETs in I'm seeing the 4.9 volts but no oscillation.
Meaning, when the amp is on, I'm seeing 4.9 volts, which is the same voltage on the gate. High side gate pin and low side drain pin has 4.9 volts but no oscillation.
Even with no FETs in I'm seeing the 4.9 volts but no oscillation.
Many of these ICs with on-board over-current protection will not produce output pulses without the FETs.
Don't reinstall the original IC if you haven't done so yet.
4.9v DC or a pulsed 50% duty cycle output with a 10v amplitude and the meter translates it as 5v DC?
Don't reinstall the original IC if you haven't done so yet.
4.9v DC or a pulsed 50% duty cycle output with a 10v amplitude and the meter translates it as 5v DC?
Ohhhhh I see.
I just did, sorry.
With my DMM it shows a duty cycle, but on the oscilloscope it doesn't show a duty cycle. And that same voltage is on the output.
I apologize if I'm not explaining it right
I just did, sorry.
With my DMM it shows a duty cycle, but on the oscilloscope it doesn't show a duty cycle. And that same voltage is on the output.
I apologize if I'm not explaining it right
You have to be far more patient than I am. I would have preferred to be (insert anything horrible and painful) than to replace that IC.
Do you have output transistors for it? Exact replacements?
Do you have output transistors for it? Exact replacements?
I'm sorry, I've been at this for awhile now and I just got 2 new ICs from digikey.
No I don't have output FETs for it but I can buy them.
This is what I'm seeing with the scope on the power supply ground and not the RCA ground.
One is the high side gate pin and the other is the low side drain pin.
Also the voltage on the CSD pin fluctuates down to 3+ volts and then up to 7+ volts.
No I don't have output FETs for it but I can buy them.
This is what I'm seeing with the scope on the power supply ground and not the RCA ground.
One is the high side gate pin and the other is the low side drain pin.
Also the voltage on the CSD pin fluctuates down to 3+ volts and then up to 7+ volts.
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Why are you buying new FETs if none are blown. Do you still have the original FETs?
I've put out a request for more information from someone who may be able to help. It may be a day or so until I get a reply. I should have asked. Do you have the diagram for the amp? If not, have you asked for it from the manufacturer?
I've put out a request for more information from someone who may be able to help. It may be a day or so until I get a reply. I should have asked. Do you have the diagram for the amp? If not, have you asked for it from the manufacturer?
Oh no I didn't buy new FETs I bought the IRS2093M IC because I thought it was bad. The fan that was coming the IC got damaged, so I thought the IC overheated and died so I bought 2 new ICs.
I got them a few days ago soldered one of them in but still have the issue, so I'm lost as to what I'm to do.
Okay thank you, there's no diagram of the amp online. But instead of going to them and getting they don't give out schematics like Hifonics, I came here.
I got them a few days ago soldered one of them in but still have the issue, so I'm lost as to what I'm to do.
Okay thank you, there's no diagram of the amp online. But instead of going to them and getting they don't give out schematics like Hifonics, I came here.
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6 terminals is OK. The center terminals are connected to ground.
Do you have one channel that producing significantly greater pulses than the others?
Do you have one channel that producing significantly greater pulses than the others?