So this amp has B31n20's and IRF9640's in the output stage.
Anyone have any history with alternates? I know I can get B38N20's, but what to use for the 9640's?
Also, 3205's acceptable in the PS?
Anyone have any history with alternates? I know I can get B38N20's, but what to use for the 9640's?
Also, 3205's acceptable in the PS?
Replace the B31n20's with IRF640's.
This amp original had the 31N20's and where switched to the 640 drop in replacements.
The IRF3205's are the original mosfets for the power supply.
This amp original had the 31N20's and where switched to the 640 drop in replacements.
The IRF3205's are the original mosfets for the power supply.
The IRF9640 (P-Channel) and the IRF640 (N-Channel) are compliments and after the 1st generation KX2500.1's only used this combo, if memory serves.
Not sure why the IRF31N20D where ever used. All other monoamps using this topology where the IRF640/IFR9640 combo.
If you only need to replace a bank of the IRF31N20D and you have them handy they will do. Otherwise you will need to replace all N channels with the IRF640. Preferable batch matched within each bank.
The Power supply mosfets IRF3205's should all be replaced with batched matched mosfets. Too often I've seen where they where not and will cause excessive idle current and fail.
I noticed you have a ZX25001. Do you know the model year? If your not sure post pictures. I didn't think the ZX had 31N20D's from the factory.
Not sure why the IRF31N20D where ever used. All other monoamps using this topology where the IRF640/IFR9640 combo.
If you only need to replace a bank of the IRF31N20D and you have them handy they will do. Otherwise you will need to replace all N channels with the IRF640. Preferable batch matched within each bank.
The Power supply mosfets IRF3205's should all be replaced with batched matched mosfets. Too often I've seen where they where not and will cause excessive idle current and fail.
I noticed you have a ZX25001. Do you know the model year? If your not sure post pictures. I didn't think the ZX had 31N20D's from the factory.
OK, did find some 9640's and got them ordered.
Working on PS - good drive with no PS fets on board. Installed PS fets and drive does not look good (see pic). Looks like there is some cross conductance.
Replaced the 2 PNP drive transistors on driver board and no difference.
Pic of board. Has quite a few components missing - assuming they came from Kicker this way?
Thanks,
Working on PS - good drive with no PS fets on board. Installed PS fets and drive does not look good (see pic). Looks like there is some cross conductance.
Replaced the 2 PNP drive transistors on driver board and no difference.
Pic of board. Has quite a few components missing - assuming they came from Kicker this way?
Thanks,
Attachments
The driver board is as it should be.
The gate drive is a result of long runs to the mosfets gates. In the final gen there where gate driver pairs added to each bank of mosfets and placed on the main board, much closer the banks they drive.
Are you getting +/- rails. 70volts?
Check the drive to the output gates and post pics.
I'm guessing this is a 2008 gen. Post pictures of main board and input board.
The gate drive is a result of long runs to the mosfets gates. In the final gen there where gate driver pairs added to each bank of mosfets and placed on the main board, much closer the banks they drive.
Are you getting +/- rails. 70volts?
Check the drive to the output gates and post pics.
I'm guessing this is a 2008 gen. Post pictures of main board and input board.
Attached requested pics.
Yes I have rail voltage and Drive on the output fets pads.
However the PS fets are heating up quickly (not sinked).
Is the PS gate drive acceptable? Seems there is a period on each cycle where each bank is on simultaneously.
Yes I have rail voltage and Drive on the output fets pads.
However the PS fets are heating up quickly (not sinked).
Is the PS gate drive acceptable? Seems there is a period on each cycle where each bank is on simultaneously.
Attachments
Is the cover silver or dark grey with red seals?
The first two generations tend to idle high.
If the IRF3205's are batch matched with the same date codes, this will be as good as it gets.
Before you install the outputs you should clamp board in the chassis and test the output drives. There are a couple more test points to check and when I can I will point them out on the the board and post.
The first two generations tend to idle high.
If the IRF3205's are batch matched with the same date codes, this will be as good as it gets.
Before you install the outputs you should clamp board in the chassis and test the output drives. There are a couple more test points to check and when I can I will point them out on the the board and post.
This is a 2006 second gen. It looks like the power supply is good and good output drive.
If the power supply mosfets are batch matched, the amp should be stable once the the board is clamped in the chassis.
I noticed the one coil was discolored and should be rewound with fresh copper, although the core may need to be replaced.
Search for threads about 2500.1's. I helped someone with rewinding an output coil, and I believe it was for a 2500.1. I will check the BOM for number of turns and core material.
If the power supply mosfets are batch matched, the amp should be stable once the the board is clamped in the chassis.
I noticed the one coil was discolored and should be rewound with fresh copper, although the core may need to be replaced.
Search for threads about 2500.1's. I helped someone with rewinding an output coil, and I believe it was for a 2500.1. I will check the BOM for number of turns and core material.
I ordered 640N by mistake. Does anyone have any history of running 640N in place of the 640's (or B31N20D) in this amp?
The 640N is the replacement we use since the 640 was made obsolete with no adverse effects.
I PM you peeby
FYI I found this on Electronics Point forum
Interestingly the datasheet for the IRF640 claims a higher single pulse avalanche rating than the IRF640N (but a lower repetitive rating)
The safe operating areas are a little different, but the IRF640N is specified at Tj of 175C whereas the IRF640 is specified at 150C.
As long as the device is not required to operate in avalanche mode at energies near the single pule limit I would have no hesitation in swapping the IRF640 for an IRF640N.
Incidentally, a ST Microelectronics datasheet for the IRF640 quotes a single pulse avalanche rating of 280mJ which is in the same ballpark as the IRF640N from your datasheet.
Hmmm
Vishay IRF640 580/13 mJ
International rectifier IR640N 247/15 mJ
ST Microelectoronics IRF640 280 mJ
Fairchild IRF640 580 mJ
Philips IRF640 580 mJ
International Rectifier IRF640 580/13 mJ
ON Semiconductor IRF640 (not specified)
SGS Thompson IRF640 280 mJ
Intersil IRF640 580 mJ
You've really got to wonder if all of these manufacturers actually measured the characteristics or copied them :-o 🙂
Given that those which define a repetitive rating have the N variant rated higher than the non-N variant, I'm sure you'll be fine.
I PM you peeby
FYI I found this on Electronics Point forum
Interestingly the datasheet for the IRF640 claims a higher single pulse avalanche rating than the IRF640N (but a lower repetitive rating)
The safe operating areas are a little different, but the IRF640N is specified at Tj of 175C whereas the IRF640 is specified at 150C.
As long as the device is not required to operate in avalanche mode at energies near the single pule limit I would have no hesitation in swapping the IRF640 for an IRF640N.
Incidentally, a ST Microelectronics datasheet for the IRF640 quotes a single pulse avalanche rating of 280mJ which is in the same ballpark as the IRF640N from your datasheet.
Hmmm
Vishay IRF640 580/13 mJ
International rectifier IR640N 247/15 mJ
ST Microelectoronics IRF640 280 mJ
Fairchild IRF640 580 mJ
Philips IRF640 580 mJ
International Rectifier IRF640 580/13 mJ
ON Semiconductor IRF640 (not specified)
SGS Thompson IRF640 280 mJ
Intersil IRF640 580 mJ
You've really got to wonder if all of these manufacturers actually measured the characteristics or copied them :-o 🙂
Given that those which define a repetitive rating have the N variant rated higher than the non-N variant, I'm sure you'll be fine.
This should work,
SK-22D02 - DAIER SK-22D02
I found them on Ebay from a stateside dealer.
10 pieces SK22D07 2P2T 6pin Mini micro small Slide Switch PCB on off B14 | eBay
SK-22D02 - DAIER SK-22D02
I found them on Ebay from a stateside dealer.
10 pieces SK22D07 2P2T 6pin Mini micro small Slide Switch PCB on off B14 | eBay