How about friends, initially this amplifier came with a short in the fets of the output stage, it is recovered and we proceed to check the pulses that a csc3120 sent, but they are not reflected and since I don't see a pulse I change the IC for an irs2092s and it tries to boost but it does not succeed and when checking the output terminals it detected voltage, I removed fets and ic and I still found 2.4v, I do not think it is normal, does anyone have experience in this type of amplifier it only has one ic drivers csc3120 for 6 fets, thank you, regards.
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Without the output FETs in the circuit, does the power supply stay up and running?
Does the 2.4v remain if you connect a dummy load across the output terminals?
Does the 2.4v remain if you connect a dummy load across the output terminals?
You are right, the voltage disappears when I place the dummy resistor although it still does not work, on pin 5 (CSD) the voltage is varying and the IC only tries to boost
Yes, the power supply works, the strange thing here is when I manage to keep it oscillating (it is not a perfect square wave) when measuring at the output terminals I also see the square wave
Reduce the 12v power supply voltage. Does the power supply waveform get more square at lower voltage?
Maybe I didn't make myself understood, I'm talking about the power supply working well, there if there is a good square wave in the output stage sometimes it manages to start, but the wave is deformed and you can look at the subwoofer terminals with the oscilloscope the same signal and voltage
What is the amplitude of the square wave on the output transistors?
Amplitude of square wave at the speaker terminals?
Oscillation frequency on the output transistors?
Oscillation frequency on the speaker terminals?
Amplitude of square wave at the speaker terminals?
Oscillation frequency on the output transistors?
Oscillation frequency on the speaker terminals?
Is the CSD pin still pulsing?
If pulsing, is it being driven to pulse internally or by an external source?
In the photo, FETs in the circuit, or out of the circuit?
If pulsing, is it being driven to pulse internally or by an external source?
In the photo, FETs in the circuit, or out of the circuit?
Good morning
Is the CSD pin still pulsing? Yes, its working
If pulsing, is it being driven to pulse internally or by an external source?It is an external source, when it remains at 5v the irs2092s starts working and you see those waveforms
In the photo, FETs in the circuit, or out of the circuit?are inside the circuit
Is the CSD pin still pulsing? Yes, its working
If pulsing, is it being driven to pulse internally or by an external source?It is an external source, when it remains at 5v the irs2092s starts working and you see those waveforms
In the photo, FETs in the circuit, or out of the circuit?are inside the circuit
If you disable whatever is dragging the CSD down, will the amp work normally on all channels?
Be careful. The pulsing could be due to a protection circuit engaging for some reason.
Be careful. The pulsing could be due to a protection circuit engaging for some reason.
What's up, I've been trying to disable what's causing that. I have not been able to identify the cause
Isn't there some component in series with the CSD line that you could lift/remove to break the connection to the pin?
You wouldn't want to break the connection to the CSD capacitor but that should be very near the IC.
You wouldn't want to break the connection to the CSD capacitor but that should be very near the IC.
Hello, how are you friends, I'm back with information regarding this amplifier. Today I checked it again and found the feedback resistor damaged (75khms), as well as that of pin 16 (csh) and I managed to make it work, the voltage of 1.9v on the output terminals is still observed when turning on and then It disappears when the IC manages to start, now the problem is that the output fets get too hot and if original 52n15 fets are being used, I only have to check the 4148 that are in each fet. I leave a photo of the frequency with which it is working at the moment
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Is the 1.9v (DC?) eliminated if you connect a load across the output until the IC starts oscillating?
Are you using a 3120 or a 2092 for the output IC?
Is there only one output driver IC?
Are you using a 3120 or a 2092 for the output IC?
Is there only one output driver IC?
Is the 1.9v (DC?) removed if you connect a load across the output until the IC starts oscillating? I haven't checked it that way, I'll try
Are you using a 3120 or a 2092 for the output IC? 3120, I don't know why the 2092 don't work, I have already tried to repair other amplifiers that originally came with 3120, I put 2092 in and they don't work
Is there only one output driver IC? it's only 1
Are you using a 3120 or a 2092 for the output IC? 3120, I don't know why the 2092 don't work, I have already tried to repair other amplifiers that originally came with 3120, I put 2092 in and they don't work
Is there only one output driver IC? it's only 1
What's not working?
Have you ever had an amp in the shop with a working 3120?
If so, what's the difference in the way the 2092 and the 3120 work?
Have you ever had an amp in the shop with a working 3120?
If so, what's the difference in the way the 2092 and the 3120 work?