hi, good evening I am working with a Stetsom HL 800.4 multi channel amp. which goes on protect mode after 2 minutes even without signal. I Replaced the outputs FETs of same parameters but the problem still the same. There are 4 banks in the output 2 FET each and driven each by IRS2092 , when the chips gets a little hot then it goes protect mode. Are the chips causing it to protect? I double check the FETs and the signal drive on the gates are identical only that there is difference of +or - 2 khz on the frequency readings. Rail to rail is good at +and - 38Vdc. I can't find any faults in the components I believed. Can anyone came to this problem, need help bros.
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no pop and DC voltage is minimal in the output. With or without signal it goes to protect mode after 2minute sometimes beyond. I put audio signal the sound is clear and not distorted. All Dc supply on the chips and rail voltages are good. is there a problem with the IRS2092 which drives the output FETS?
Is there a solder bridge in this amp that allows you to disable the protection by removing it?
Measure the voltage on all terminals of the microcontroller (if it has one). Compare the voltages when working normally and the voltages measured when in protect.
Measure the voltage on all terminals of the microcontroller (if it has one). Compare the voltages when working normally and the voltages measured when in protect.
I found more information on this amp. It doesn't appear to use a microcontroller.
Monitor the voltage on the SD pin of the SG3525. What's the voltage when the amp starts initially, when the amp shuts down? Does it vary between those two points in time?
Monitor the voltage on the SD pin of the SG3525. What's the voltage when the amp starts initially, when the amp shuts down? Does it vary between those two points in time?
hi bro, upon power ON, the initial Vdc at Pin #10 with respect to negative was 0.127 V after about 1minute the voltage gradually increases at an increment of .002 volts until after 10 secs. it jumps suddenly to 1.752 v and goes to protect mode. Does this indicate something heating up at the output?
As shown in the picture their is no Q20 near the SG3525 chip instead their is Q13(6CW). I tried removing the the Q13 and it did not protect. Maybe the Q13 is leaking? The only thing was the driver chips for the output FETs are getting hot but i believe this is normal, the gate signals on output the FETs are the same as well. Can I run the amp without the Q13?
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With Q13 out of the circuit, what is the DC voltage on each of the CSD terminals of the output driver ICs?
Don't slip when measuring the voltage.
For testing, it may be safe to run without Q13 but as always when defeating part of the protection circuit, you have to be very careful/observant. I'd suggest having the semiconductors tightly clamped to the heatsink when possible.
Don't slip when measuring the voltage.
For testing, it may be safe to run without Q13 but as always when defeating part of the protection circuit, you have to be very careful/observant. I'd suggest having the semiconductors tightly clamped to the heatsink when possible.
Output Driver IC 1 Pin 5(CSD) = 5.59 Vdc
Output Driver IC 2 Pin 5(CSD) = 2.53 Vdc
Output Driver IC 3 Pin 5(CSD) = 5.57 Vdc
Output Driver IC 4 Pin 5(CSD) = 5.53 Vdc
Output Driver IC 2 which is channel 2 has different CSD DC Voltage from the rest that is why when I tested with signal, the output signal to the FETs gate are not stable, i tried with audio and the sound was sometimes goes very weak. I believe this IC driver is having a problem which causes the amp to protect. Is it?
Output Driver IC 2 Pin 5(CSD) = 2.53 Vdc
Output Driver IC 3 Pin 5(CSD) = 5.57 Vdc
Output Driver IC 4 Pin 5(CSD) = 5.53 Vdc
Output Driver IC 2 which is channel 2 has different CSD DC Voltage from the rest that is why when I tested with signal, the output signal to the FETs gate are not stable, i tried with audio and the sound was sometimes goes very weak. I believe this IC driver is having a problem which causes the amp to protect. Is it?
The circuit board designation of the output driver IC2 i was referring is U12 which is an IRS2092S audio amplifier which is driving 2 FETS (IRF540N) in one channel.
If C93 isn't defective, I think the IC may be defective. Bear in mind that I'm not very familiar with this IC.