The output transistors had low R-values, short when powering up, desoldered the ones that were bad and the amp powered up normally.
I couldn´t find the datasheet on the web, https://www.jotrin.com/product/parts/MAP6808, I asked jotrin via e-mail and they don´t have it.
https://www.made-in-china.com/showroom/musitech/
Musitech themselves aren´t better either, I found at least someone with their name on the internet, but they only have a phone number after the resgistration, I will try to inquire over the website, maybe in the meantime anybody knows this transistor, or can navigate the web better than me.
thank you all in advance.
I couldn´t find the datasheet on the web, https://www.jotrin.com/product/parts/MAP6808, I asked jotrin via e-mail and they don´t have it.
https://www.made-in-china.com/showroom/musitech/
Musitech themselves aren´t better either, I found at least someone with their name on the internet, but they only have a phone number after the resgistration, I will try to inquire over the website, maybe in the meantime anybody knows this transistor, or can navigate the web better than me.
thank you all in advance.
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.
Pull one of the remaining good outputs and check it to see if it's an FET or a bipolar transistor.
It's an IGBT transistor.
I'm pretty sure MUSITECH does not make these for years now. The other manufacturer who made those was Toshiba back in the days.
You can find them under the name: Toshiba GT*D** .
A lot of the Hifonics Zeus amps back in the days used the same type of drivers, outputs and circuit. Depending on the rail voltage and current requirements they would use different IGBT output transistor either from MUSITECH model GT** or Toshiba GT*D but often marked as MAP *****.
How to find the exact one You need is no easy task, but buying an original working one as they are discontinued is almost mission impossible. Please find the picture attached. This were the ones used in of the 4 channel Hifonics Zeus amplifiers I repaired maybe a year ago.
I got incredibly lucky, a local shop had 4 in stock laying around for ages.
To this day I don't know if there are any substitutes, circuits are really fickle about the IGBT being used.
I think the other package they are also available is in the second picture.
Hope that clarifies the things a little bit....I've spend numerous nights researching this topic....Kind-a reminds me of the class T Tripath amplifiers....if the IC dies you are basically screwed...
I'm pretty sure MUSITECH does not make these for years now. The other manufacturer who made those was Toshiba back in the days.
You can find them under the name: Toshiba GT*D** .
A lot of the Hifonics Zeus amps back in the days used the same type of drivers, outputs and circuit. Depending on the rail voltage and current requirements they would use different IGBT output transistor either from MUSITECH model GT** or Toshiba GT*D but often marked as MAP *****.
How to find the exact one You need is no easy task, but buying an original working one as they are discontinued is almost mission impossible. Please find the picture attached. This were the ones used in of the 4 channel Hifonics Zeus amplifiers I repaired maybe a year ago.
I got incredibly lucky, a local shop had 4 in stock laying around for ages.
To this day I don't know if there are any substitutes, circuits are really fickle about the IGBT being used.
I think the other package they are also available is in the second picture.
Hope that clarifies the things a little bit....I've spend numerous nights researching this topic....Kind-a reminds me of the class T Tripath amplifiers....if the IC dies you are basically screwed...
Attachments
Jeah you are right, seems to be a FET.
GDS layout from topview I assume, DS stays switched on.
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Thank you very much for your answer Lenin89.
Hmm, now that´s discouraging but still fascinating
I will search some more for this part, with a datasheet it is easier to find something.
GDS layout from topview I assume, DS stays switched on.
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Thank you very much for your answer Lenin89.
Hmm, now that´s discouraging but still fascinating
I will search some more for this part, with a datasheet it is easier to find something.