Protection on deaf bounce 2000.1

[legion2710]

Working on this amp ..5 output mosfet was bad.i changed them out and it still on protect mode ..I even took out all the output mosfets to see if it come back on.i still is on protect .any one ever worked on these amp

 

[Perry Babin]

Post a good quality photo of the component side of the entire main board and the component side of any driver boards if no one can help.

 

[legion2710]

I carries no drive board

 

[Perry Babin]

Are the same exact components installed/missing as in the photo?

Are the PS FETs getting drive and is the PS producing positive and negative rail voltage as well as positive and negative regulated 15v?

 

[legion2710]

Yes.. only the protection led on...but when I switch of the powersupply the power led comes on for a second.

 

[Perry Babin]

Yes to both?

Are you saying that the power supply remains on while the amp is in protect?

 

[legion2710]

Yes ..the high voltage are present even if the protection is on ..and when I take off the 12 volt powersupply I use for testing .for a second the power led comes on .

 

[Perry Babin]

Post a photo of the components in the PS driver circuit that's good enough to read the values and the circuit board designations. I'm trying to find a diagram that may help with troubleshooting.

 

[laluns]

Hi

That board looks almost the same as the DD DM2500.1

The PMW circuit is on the board see picture below. What I have found on DD board when the outputs fails sometimes the buffer transistors fail as well. These transistors are SMD type. Check those transistor out.

From the picture that you have posted I have circled the PWM circuit for you.

 

[Perry Babin]

If it's like the DD2500, there isn't much that can keep the amp in protect and the supply running.

When in protect, do you have output pulses (pins 9 and 10) from the TL494 driver IC?

When in protect, is the power LED on at the same time that the protect LED is on? Or does the power LED only flash as the remote voltage is removed?