Ground zero GZPA 1.4000DXII

[killerkeoki]

Hi, I have this Ground zero GZPA 1.4000DXII I need help identifying parts numbers for the IC's that are scratched off.

This amp had a blown power supply and output. I repaired the power supply, but I get no class d switching. I can hear light ticks from the output. Please help!

Thanks

 

[rrae]

2x IRS21844S
U3 TL072
U4 LM311

Always, when working with this type of output card, after outputs were blown, replace 21844!

 

[killerkeoki]

2x IRS21844S
U3 TL072
U4 LM311

Always, when working with this type of output card, after outputs were blown, replace 21844!

Thank you! I will order tonight.

 

[killerkeoki]

2x IRS21844S
U3 TL072
U4 LM311

Always, when working with this type of output card, after outputs were blown, replace 21844!

Hi rrae,

I replaced the irs21844s, but I'm still having the same issue. Should I have replaced u3, and U4 at the same time. Thank you for your help.

 

[MarioRestucci]

Hi rrae,

I replaced the irs21844s, but I'm still having the same issue. Should I have replaced u3, and U4 at the same time. Thank you for your help.

can u remove the driver board from the amp?
so, take a high resolution photo and post here!

 

[killerkeoki]

can u remove the driver board from the amp?
so, take a high resolution photo and post here!

Hi,

Is there a certain area you would like me to take a picture of?

Thanks

 

[MarioRestucci]

Hi,

Is there a certain area you would like me to take a picture of?

Thanks

all the driver board.
Is very easy that are defective transistor between lm311 and both irs21844

 

[killerkeoki]

all the driver board.
Is very easy that are defective transistor between lm311 and both irs21844

 

[Perry Babin]

There is a test procedure that allows you to check for signal at various points. There are a few variations. The following thread is the procedure for a similar amp.

For most amps, you solder a 10k resistor between pins 1 and 2 of the TL072. Then you solder a bridge between legs 2 and 3 of the 21844. Driving a strong low frequency signal (50Hz-100Hz), if the circuit is working correctly, you will be able to see a square wave at the output of the TL072, at the output of the LM211 and at the input of the 21844.

Checking PWM signal on Class-D amps using IRS21844S problems

 

[MarioRestucci]

There is a test procedure that allows you to check for signal at various points. There are a few variations. The following thread is the procedure for a similar amp.

For most amps, you solder a 10k resistor between pins 1 and 2 of the TL072. Then you solder a bridge between legs 2 and 3 of the 21844. Driving a strong low frequency signal (50Hz-100Hz), if the circuit is working correctly, you will be able to see a square wave at the output of the TL072, at the output of the LM211 and at the input of the 21844.

Checking PWM signal on Class-D amps using IRS21844S problems

what is the function of the 10k resistor?
i've understand that the bridge between pin 2 & 3 of irs21844 force the chip to shutdown her output, but the resistor?

 

[Perry Babin]

There is no feedback without the amp working normally. The open feedback loop can make the op-amp do strange things. The 10k feedback resistor allows the op-amp to function as an audio amplifier. If the output of the op-amp is clean audio, you can see that the op-amp is functioning normally and can move on to the next stage of troubleshooting.

 

[MarioRestucci]

There is no feedback without the amp working normally. The open feedback loop can make the op-amp do strange things. The 10k feedback resistor allows the op-amp to function as an audio amplifier. If the output of the op-amp is clean audio, you can see that the op-amp is functioning normally and can move on to the next stage of troubleshooting.

thanks for the info.

 

[nbv]

Hi!
PerryBabin:
1.”…you will be able to see a square wave at the output of the TL072”
2.” Ifthe output of the op-amp is clean audio…”

At theoutput of the TL072, with soldered 10K, audio signal or a square wave?

 

[Perry Babin]

Please don't post in a repair thread that was started by someone else unless you are trying to help them.

Include a link to this thread if you want to use it as a reference.

Start a new thread. After it's moved, I'll try to help you.