Received an email from client he stated the amp was playing fine then went into protection. So put it on the bench the amp is in protection it tries to power on briefly before going in protect the power supply Fet's we're all good same with the output side.
I took the rectifiers out of the amp and it stayed in protect after removing the output driver board the amp finally powered on and it had great drive waves for power supply so I put the rectifiers back in and new IR21844s on output driver board also checked the ES2G diodes and small caps on the board and they checked out fine as well as checking gate resistors and pull down resistors in power and output side all seemed well.
But when I put the output driver board in the amp it would go back to protection so taking the output board out of the amp I use Perry's guide on class d type 3 for driver board layout and tested each pin and I have -45.37v on the shutdown/protect legs 6 & 16. The output board is not a dwm3640 but I believe a clone and is essentially the same pic is below. I've checked everything I can think of and read a few threads on here can't find any that correlate to my issue or could just be a lack of knowledge on my part anyone that could help would be much appreciated.
I took the rectifiers out of the amp and it stayed in protect after removing the output driver board the amp finally powered on and it had great drive waves for power supply so I put the rectifiers back in and new IR21844s on output driver board also checked the ES2G diodes and small caps on the board and they checked out fine as well as checking gate resistors and pull down resistors in power and output side all seemed well.
But when I put the output driver board in the amp it would go back to protection so taking the output board out of the amp I use Perry's guide on class d type 3 for driver board layout and tested each pin and I have -45.37v on the shutdown/protect legs 6 & 16. The output board is not a dwm3640 but I believe a clone and is essentially the same pic is below. I've checked everything I can think of and read a few threads on here can't find any that correlate to my issue or could just be a lack of knowledge on my part anyone that could help would be much appreciated.
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I'm assuming that you've confirmed that all of the power supplies feeding that board are as they should be.
Connect the driver board on jumper wires (Arduino breadboard jumpers if you have them) so that you can access all parts of the board while the board is in the amp.
Removing R21 should completely disable the over-current protection. That's the only protection on this type of board.
That can be risky if there is a fault that's causing a real over-current condition. Using low-rail voltage significantly reduces the risk.
Connect the driver board on jumper wires (Arduino breadboard jumpers if you have them) so that you can access all parts of the board while the board is in the amp.
Removing R21 should completely disable the over-current protection. That's the only protection on this type of board.
That can be risky if there is a fault that's causing a real over-current condition. Using low-rail voltage significantly reduces the risk.
Yes perry i have checked all the voltage regulators and have all the correct voltages.
I will solder the output board in on jumpers and remove r21 and will post what I find.
Should I remove some main rail caps to reduce the rail voltage if so how many would you suggest? There are 12 main rail caps in the middle of board.
I will solder the output board in on jumpers and remove r21 and will post what I find.
Should I remove some main rail caps to reduce the rail voltage if so how many would you suggest? There are 12 main rail caps in the middle of board.
Removing the rail caps won't reduce the voltage.
There isn't much risk to anything other than the 21844s if the outputs are out of the circuit.
For the low-voltage (covered in the tutorial, item 17 on the type-3 page) is also on the forum:
https://www.diyaudio.com/forums/car-audio/319174-4000-1-a-7.html#post5492949
There isn't much risk to anything other than the 21844s if the outputs are out of the circuit.
For the low-voltage (covered in the tutorial, item 17 on the type-3 page) is also on the forum:
https://www.diyaudio.com/forums/car-audio/319174-4000-1-a-7.html#post5492949
Your are right it was supposed to say rail voltage current for removing the caps sorry.
Ok the amp does power on and the drivers don't heat up to crazy and I did get a low side drive with audio injected pic below.
When I went to remove the scope probe from the lowside gate pad it sparked just alil on the 100k ohm pull down resistor but stayed on.
Also noticed alil whinny noise that is faint but will come and go and when it came I tried twisting the transformers and inductors but they mad no change and are glue very well considering the board qauilty.
SCOPE SETTINGS ARE( .2us 5v) probe x10
Ok the amp does power on and the drivers don't heat up to crazy and I did get a low side drive with audio injected pic below.
When I went to remove the scope probe from the lowside gate pad it sparked just alil on the 100k ohm pull down resistor but stayed on.
Also noticed alil whinny noise that is faint but will come and go and when it came I tried twisting the transformers and inductors but they mad no change and are glue very well considering the board qauilty.
SCOPE SETTINGS ARE( .2us 5v) probe x10
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I love the scope. I have a 453 that's in museum quality condition (like yours appears to be). It still works well (perfectly, except for a few scratchy pots).
The scope probe should not have sparked. Maybe you got close enough to another trace/ground plane to short between them.
Using a 9v battery, you should be able to get high-side drive. The low-voltage option is a good one because you can install all parts and have the amp function normally but with reduced risk, if you think there may be a problem.
The scope probe should not have sparked. Maybe you got close enough to another trace/ground plane to short between them.
Using a 9v battery, you should be able to get high-side drive. The low-voltage option is a good one because you can install all parts and have the amp function normally but with reduced risk, if you think there may be a problem.
Thanks that's cool coming from you man I bought it a few years back off letgo for 60.00 and it's been a champ I like it way better then these newer scopes I have.
Ok so if I'm getting the gist of this you want me to install the outputs or (1 per bank) and then solder a 9 volt battery across the negative rail caps? To check the high side drive.
Do I solder the positive side of 9v battery to the positive side of the negative rail caps and negative side of 9v battery to the negative side of the negative rail caps.
Do I power amp on after or leave off
Ok so if I'm getting the gist of this you want me to install the outputs or (1 per bank) and then solder a 9 volt battery across the negative rail caps? To check the high side drive.
Do I solder the positive side of 9v battery to the positive side of the negative rail caps and negative side of 9v battery to the negative side of the negative rail caps.
Do I power amp on after or leave off
I bought the DVD a few years back so I don't know if you've updated it from since I've got it but I don't see anything about the 9-volt battery item #2 or item #17
I've read threw class d type3 and it's stops at 15. Replacement output transistors am I overlooking something I'm just not seeing it
I've read threw class d type3 and it's stops at 15. Replacement output transistors am I overlooking something I'm just not seeing it
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