GaNFETs in Audio Amps

Certainly switchmode, not linear.

There are a bunch of named classes, but all are basically class D.

GaNs can switch really fast, which for a given power makes things small. Aside from that, they have no real advantages over mosfets.

A delta-sigma GaN amp might be fun.

But audio makes no sense, which is why people still spend big on turntables and tubes.

John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics

There are actually sensible people involved in audio, and good quality amplifiers and loud speakers are worth paying for.

Audiofools pay absurd money for essentially bizarre speakers and amplifiers that don't perform any better than regular good quality stuff, and sometimese perform quite a bit worse.

I once gave my father some qood quality headphones - Sennheiser 480's - and they performed a whole lot better than the equally expensive headphones that his audio shop in Melbourne had sold him. He was surprised. I snaffled them back after he died - my mother wasn't into headphones.

So what else are they suited to?

GaN? Lots of things.

We're using them in fast switches, the output stages of this:

GaN is used in tiny wall warts. And for RF stuff. I think some microwave ovens use them instead of magnetrons.

Their figures of merit, amps/pF and such, are astounding. And they turn on hard with 5-volt gate drive.

John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics

Got a ballpark Rdson?

There are a zillion parts. Some of the tiny EPC things get down to

This is 650v and 190m.

John Larkin Highland Tech Glen Canyon Design Center Lunatic Fringe Electronics

Wow! I thought you were going to say 0.01 Ohms or somethin' like it. I am *so* far behind the times!

"Cursitor Doom" snipped-for-privacy@notformail.com wrote in message news: snipped-for-privacy@4ax.com...

You can have fun with them in audio amplifiers if you want. But there are many reasons why I won't be putting this into production any time soon. It takes very little adjustment of R16 to blow up the FETs.

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976 WIRE -1568 1024 -1568 976 FLAG 816 -64 Vs6 FLAG 864 496 Vout5 FLAG -1568 1024 0 FLAG -64 640 In+3 FLAG -800 128 Byp7 FLAG -496 368 Gain8 FLAG -256 368 Gain1 FLAG -1072 640 In-2 FLAG -1472 144 0 FLAG -928 272 0 SYMBOL npn 416 176 R0 SYMATTR InstName Q1 SYMATTR Value 2N3904 SYMBOL pnp 272 192 M180 WINDOW 0 -51 25 Left 2 WINDOW 3 -54 -5 Left 2 SYMATTR InstName Q2 SYMATTR Value 2N3906 SYMBOL diode 176 -32 M0 WINDOW 0 47 32 Left 2 WINDOW 3 -78 31 Left 2 SYMATTR InstName D1 SYMATTR Value 1N914 SYMBOL diode 176 32 M0 WINDOW 0 49 30 Left 2 WINDOW 3 -83 30 Left 2 SYMATTR InstName D2 SYMATTR Value 1N914 SYMBOL res 352 -32 M0 SYMATTR InstName R1 SYMATTR Value 330 SYMBOL res 144 656 R0 SYMATTR InstName R2 SYMATTR Value 10k SYMBOL pnp 416 752 M180 WINDOW 0 -31 88 Left 2 WINDOW 3 40 52 Left 2 SYMATTR InstName Q3 SYMATTR Value 2N3906 SYMBOL npn 272 832 R0 WINDOW 0 -22 -1 Left 2 WINDOW 3 -60 106 Left 2 SYMATTR InstName Q5 SYMATTR Value 2N3904 SYMBOL res -48 448 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R3 SYMATTR Value 15k SYMBOL voltage -1568 480 R0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V1 SYMATTR Value 18 SYMBOL pnp -304 608 R180 WINDOW 0 72 31 Left 2 WINDOW 3 45 61 Left 2 SYMATTR InstName Q6 SYMATTR Value 2N3906 SYMBOL pnp -160 688 R180 WINDOW 0 72 31 Left 2 WINDOW 3 45 61 Left 2 SYMATTR InstName Q7 SYMATTR Value 2N3906 SYMBOL res -128 704 R0 SYMATTR InstName R4 SYMATTR Value 50k SYMBOL pnp -816 608 M180 WINDOW 0 72 31 Left 2 WINDOW 3 45 61 Left 2 SYMATTR InstName Q8 SYMATTR Value 2N3906 SYMBOL pnp -960 688 M180 WINDOW 0 72 31 Left 2 WINDOW 3 45 61 Left 2 SYMATTR InstName Q9 SYMATTR Value 2N3906 SYMBOL res -576 448 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R5 SYMATTR Value 150 SYMBOL res -432 448 R90 WINDOW 0 0 56 VBottom 2 WINDOW 3 32 56 VTop 2 SYMATTR InstName R6 SYMATTR Value 1.35k SYMBOL res -768 -16 R0 SYMATTR InstName R7 SYMATTR Value 15k SYMBOL res -768 160 R0 SYMATTR InstName R8 SYMATTR Value 15k SYMBOL res -1040 704 R0 SYMATTR InstName R9 SYMATTR Value 50k SYMBOL npn -432 832 R0 SYMATTR InstName Q10 SYMATTR Value 2N3904 SYMBOL npn -688 832 M0 SYMATTR InstName Q11 SYMATTR Value 2N3904 SYMBOL voltage -1408 736 R0 WINDOW 123 0 0 Left 0 WINDOW 39 0 0 Left 0 SYMATTR InstName V2 SYMATTR Value SINE(0 100m 1000) SYMBOL cap -1264 624 R90 WINDOW 0 0 32 VBottom 2 WINDOW 3 32 32 VTop 2 SYMATTR InstName C1 SYMATTR Value 1000n SYMBOL polcap -1488 16 R0 SYMATTR InstName C2 SYMATTR Value 47000n SYMBOL polcap -944 144 R0 SYMATTR InstName C3 SYMATTR Value 47000n SYMBOL GAN190-650FBE 752 304 R0 WINDOW 0 32 -48 Left 2 WINDOW 3 32 48 Left 2 SYMATTR InstName U1 SYMBOL GAN190-650FBE 752 784 R0 WINDOW 0 32 -48 Left 2 WINDOW 3 32 48 Left 2 SYMATTR InstName U2 SYMBOL res 496 -16 M0 SYMATTR InstName R10 SYMATTR Value 2.2k SYMBOL res 608 832 R0 SYMATTR InstName R11 SYMATTR Value 2.2k SYMBOL diode 320 272 R0 WINDOW 0 42 29 Left 2 WINDOW 3 -85 29 Left 2 SYMATTR InstName D4 SYMATTR Value 1N914 SYMBOL diode 320 368 R0 WINDOW 0 42 29 Left 2 WINDOW 3 -85 29 Left 2 SYMATTR InstName D5 SYMATTR Value 1N914 SYMBOL polcap 1008 576 R0 SYMATTR InstName C4 SYMATTR Value 470000n SYMBOL res 1008 752 R0 SYMATTR InstName R12 SYMATTR Value 15 SYMBOL pnp 576 176 M180 WINDOW 0 -31 88 Left 2 WINDOW 3 40 52 Left 2 SYMATTR InstName Q4 SYMATTR Value 2N3906 SYMBOL res 656 320 M0 SYMATTR InstName R14 SYMATTR Value 2.2k SYMBOL pnp 560 672 M180 WINDOW 0 -31 88 Left 2 WINDOW 3 40 52 Left 2 SYMATTR InstName Q12 SYMATTR Value 2N3906 SYMBOL res 496 496 M0 SYMATTR InstName R15 SYMATTR Value 2.2k SYMBOL diode 320 496 R0 WINDOW 0 42 29 Left 2 WINDOW 3 -85 29 Left 2 SYMATTR InstName D3 SYMATTR Value 1N914 SYMBOL res 496 304 M0 SYMATTR InstName R13 SYMATTR Value 2.2k SYMBOL res 352 576 M0 SYMATTR InstName R16 SYMATTR Value 420 TEXT 1056 960 Left 2 ;Gnd4 TEXT -1560 -176 Left 2 ;LM386 simulation with GaN FET output\nJanuary 2026\nSimulation requires