Semisouth goes Dodo ; what now ?

probably similar to why A123 did, (perhaps without the mismanagement, I guess we'll see what comes out) over-capitalization banking on a market (solar and EV) that isnt quite there yet. A market that stupidly has had money diverted away from it towards nuclear due to renewed development in that area and new uranium markets and supply opening up (i'm looking at you Australia...)

oops politics...

well we can at least hope that the people at the university who own some of the patents and all the fabs will do something with the technology, whether they will sell it to small buyers of course is another thing
 
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Why not use a LDMOS transistor like BLF578(XR) for ultra high quality Class A amps ?

Seriously:

Why not using a NXP BLF578XR in a Push-Pull-Class A amplifier using a PP output transformer ?

Or even build a stereo Single ended Class A amp with a single Transistor.

The BLF578(XR) contains two 500W Transistors with grounded common source in a single package.

Crss is 5.5pF per Transistor, so a ZEN could be built without the inherent huge amount of nonlinear cap parallel to the feedback resistor, which produces as much PIM like a FM radio transmitter, if you use an ordinary V-MOSFET .. !?

So why bother with SiC Switching Transistors, if you can buy a linear Transistor which is so superior ?
 
As far as I understand, they didn't have any serious competition in SiC JFets and maybe other SiC components.
So does anyone know why they went bankrupt ?

Probably nobody needs SiC transistors in plastic housings, which only take 150W and 150°C, except perhaps the over-subsidized solar energy market, which just turned into another bubble.

And: Recent advancements in silicon super junction (coolMOS) transistors ate up a large portion the efficiency and voltage advantage ...

And: The competition in the field of SiC diodes is pretty big, there are plenty players, some of them being IXYS, Rohm and other bigger players.
 
Take the MRFE6VP5600HR5, you get it from Mouser and DigiKey in single quantities.

1667W total device power dissipation for 158USD and Crss 1.6pF, Ciss 342pF !!!!!

No SiC-switching-transistor will ever reach this performance !

Silicon LDMOS for RF is a bargain, if you compare it to SiC.
 
yes, but we are not talking about RF are we? have you actually used it for audio, or just going by the numbers presented? what typical match between the 2 devices? I wouldnt want to buy 100 x 290usd devices to match... I think you will find the power of this device is drastically reduced for linear audio applications, particularly Class A, when its designed for Class C
 
1667W on 25 degrees C. 1.6/345 above 30V, breakdown voltage is 120V. Can't find transfer curves usable for audio applications.
I would check IXYS RF for laterals
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BTW Infineon makes the same staff as semisouth... samples for now.
I've been told on PCIM that HV Jfets will die out as soon as decent MOSFET gate could be developed
One can't make carbon oxide gate insulator ;-) seems that nothing dielectric adheres good enough to SiC
 
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Take the MRFE6VP5600HR5, you get it from Mouser and DigiKey in single quantities.

1667W total device power dissipation for 158USD and Crss 1.6pF, Ciss 342pF !!!!!

No SiC-switching-transistor will ever reach this performance !

Silicon LDMOS for RF is a bargain, if you compare it to SiC.

I am playing with much smaller versions of the above, if you like, check out Renesas RD16HHF1 (TO220, Glyn, $3-5/ea). I was hoping to discover Nirvana. Instead, as good as they sound an measure, they are not exactly layout tolerant - when they take off (and they DO take off, especially when paralleled) the action is at >200MHz. For starters, we are talking ~1K Gate de-Q resistors, and I am now thinking of a proper RF layout for an audio amp.

I would be curious to see some results on the MRFE's :)
 
I am playing with much smaller versions of the above, if you like, check out Renesas RD16HHF1 (TO220, Glyn, $3-5/ea). I was hoping to discover Nirvana. Instead, as good as they sound an measure, they are not exactly layout tolerant - when they take off (and they DO take off, especially when paralleled) the action is at >200MHz. For starters, we are talking ~1K Gate de-Q resistors, and I am now thinking of a proper RF layout for an audio amp.

I would be curious to see some results on the MRFE's :)

Could you point us to a link to this ? Google throws up lots of strange mitsibusy devices not sure if it's the same... Also what's Glyn and where can we try n buy these lil critters ? Cheers