This one should be simple to fix. One of the FETs in one supply is missing a source leg, which was causing the power supply to fail to boot (Protect). Clipping that one FET off and the amp totally works. I think I can just replace the 4x FETs in this 1 (out of the 6 PSs), that is if I can source a replacement for IRFB438 that'll match all other power supplies in this amp. IRFB438 is a new one for me. Seems to only be available out of Brazil? Not totally sure on these.
4.7 ohm gate resistors. Looks like this is a microprocessor controlled amp, uses several 2n7524AF drivers.
IRFB438...
4.7 ohm gate resistors. Looks like this is a microprocessor controlled amp, uses several 2n7524AF drivers.
IRFB438...
Could the driver actually be a UCC27524DGNR?
It's odd, that with so many open part numbers, that IR would go bank to 3 digits.
It's odd, that with so many open part numbers, that IR would go bank to 3 digits.
OK. Octopart failed me. A different search led to this:
https://www.infineon.com/dgdl/Infin...N.pdf?fileId=5546d462525dbac40152abcc7dbb1727
For the FETs, I think you'll need to perform an RDSon test of some sort to see approximately what they compare to if you can't find the originals.
https://www.infineon.com/dgdl/Infin...N.pdf?fileId=5546d462525dbac40152abcc7dbb1727
For the FETs, I think you'll need to perform an RDSon test of some sort to see approximately what they compare to if you can't find the originals.
Comparing; UCC27324DR as seen in taramps hd3000/3k. Those use irf1404.
What are the gate and pulldown resistor values in a taramp hd3000? I’m thinking this amp is just 6 times more power supplies than that little taramp. Comparably both amps are microprocessor controlled.
irf1404 are the strongest I have in stock.
What are the gate and pulldown resistor values in a taramp hd3000? I’m thinking this amp is just 6 times more power supplies than that little taramp. Comparably both amps are microprocessor controlled.
irf1404 are the strongest I have in stock.
Ok. Maybe those might work.
I’m going to call irf tomorrow and see if they can get a data sheet or more info on irfb438. That said I do see this Brazilian site and apparently irfb438 are 160A and irfb3207 may be a sub?
https://produto.mercadolivre.com.br/MLB-967613550-irfb438-mosfet-original-modulo-banda-_JM
I’m going to call irf tomorrow and see if they can get a data sheet or more info on irfb438. That said I do see this Brazilian site and apparently irfb438 are 160A and irfb3207 may be a sub?
https://produto.mercadolivre.com.br/MLB-967613550-irfb438-mosfet-original-modulo-banda-_JM
The specs vary from 60v, 160A to 40v, 195A from what I found. Hopefully IR will be able to give you a good sub,
No response back from IRF.
So, the way this amp starts is soft. First it using low duty faint PWM - sort of like some Taramps - very faint at first. Then after about 10 second (Unmutes) the amp then runs completely un-regulated. Changing supply voltage and the supply is always un-regulated. So its running essentially full tilt on the PS Fets always.
I'm thinking the 2n7524AF may work with most any fets I've mentioned above. I'm seriously contemplating trying IRF1404 just in this ONE PS bank to see how it goes; signal wise, heat etc. Then move forward with IRF1404 (48 units).
So, the way this amp starts is soft. First it using low duty faint PWM - sort of like some Taramps - very faint at first. Then after about 10 second (Unmutes) the amp then runs completely un-regulated. Changing supply voltage and the supply is always un-regulated. So its running essentially full tilt on the PS Fets always.
I'm thinking the 2n7524AF may work with most any fets I've mentioned above. I'm seriously contemplating trying IRF1404 just in this ONE PS bank to see how it goes; signal wise, heat etc. Then move forward with IRF1404 (48 units).
Why not perform a test (time consuming but not complex) to compare the originals to the 1404s?
If you replace all of them, no comparison is needed but you must make sure that the replacement is at least equal to the originals?
If you replace all of them, no comparison is needed but you must make sure that the replacement is at least equal to the originals?
IRF returned my message, and said IRFB438 are not publicly available as they were a special custom part/build for a customer. They did recommend IRFB7437 as an alternate. I'll add those to my inventory as those seems to be a great sub probably for both IRFB438, IRFB3207, and probably IRF1404 in power supplies. They're almost just only 1$ each too.
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I don't understand why manufacturers do this. Any competent engineer could reverse engineer their products in less than a day. The only people that are hurt by the policy are the owners of the amps and the repair techs.
To clarify, in the US, an (electronics) engineer is someone with a degree in electronics who is capable of designing the circuits. In some countries, repair technicians (US designation) are referred to as engineers.
To clarify, in the US, an (electronics) engineer is someone with a degree in electronics who is capable of designing the circuits. In some countries, repair technicians (US designation) are referred to as engineers.
Hi Just my 2 cents on this as I work with a lot of the Brazilian amps it will better to replace all the FETS with the same type. These Brazilian amps don't like when you use different Mosfets. For your drive IC you can use the following (1) IR4427 or (2) 2EDN7524AF or UCC27524.
With the gate drivers just make sure that pins 1,6 and 8 all go to 12v pin 3 GND, Pins 2 and 4 are your inputs and pins 5 and 7 are outputs.
Hope this helps you.
With the gate drivers just make sure that pins 1,6 and 8 all go to 12v pin 3 GND, Pins 2 and 4 are your inputs and pins 5 and 7 are outputs.
Hope this helps you.
I was referring to the manufacturers making it difficult to find replacement parts by using a special part number, defacing the part or marking a part with a real part number that's NOT the part that's installed. The latter has happened with various logic ICs.
The same thing for schematic diagrams. It makes no sense to keep them from the general public.
The same thing for schematic diagrams. It makes no sense to keep them from the general public.
9 times out of 10 if the drivers are blown in this one, the PIC is blown. I know a guy whos in development of a work around and is almost complete.
438 is restamped 3077, the gate drivers ive used in the past are 2EDN7524FXTMA1.
IRF 1404 are used for replacements.
Sam at Barevids from youtube could tell you loads of info about these.
438 is restamped 3077, the gate drivers ive used in the past are 2EDN7524FXTMA1.
IRF 1404 are used for replacements.
Sam at Barevids from youtube could tell you loads of info about these.
Posts moved to a new thread:
https://www.diyaudio.com/community/threads/viking-15-000-doesnt-power-on.413235/
Hugo
https://www.diyaudio.com/community/threads/viking-15-000-doesnt-power-on.413235/
Hugo