200 W GaN Audio Amplifier Kit

[DonH56]

See first article. I don't know any more than that but thought it might be of interest.

https://www.electronicdesign.com/po...da|9938I0589789A1T&oly_enc_id=9938I0589789A1T

 

[NTK]

The bundle GS-EVB-AUD-BUNDLE1-GS (which includes the SMPS) is listed at Mouser for $995 and expected availability is June 30.
https://www.mouser.com/ProductDetail/GaN-Systems/GS-EVB-AUD-BUNDLE1-GS?qs=vHuUswq2%2BszP6hR0ubJmfw==

 

[Icboschert]

Looks to be around $950-$1000 for the kit

https://www.richardsonrfpd.com/Products/Product/GS-EVB-AUD-BUND#

https://www.mouser.com/ProductDetail/GaN-Systems/GS-EVB-AUD-BUNDLE1-GS?qs=vHuUswq2%2BszP6hR0ubJmfw==

 

[EB1000]

The most important parameter is not mentioned. GaN can operate at switching frequencies ranging from 1MHz to 50MHz. Most silicon-based class-D amps operate at a 500kHz average frequency, with some boutique designs reaching 750kHz. No point in using GaN if the switching freq does not exceed at least 1MHz...

 

[DonH56]

I thought GaN offered efficiency improvements even at lower frequencies due to the intrinsic bandgap advantage? Maybe not, my world is well above audio... Though the SMPS we use in some of our products have gone beyond 1 MHz now.

 

[Dave Zan]

The most important parameter is not mentioned....Most silicon-based class-D amps operate at a 500kHz...

I downloaded their "whitepaper" and they switch at 400 kHz - like you, I can't see much benefit at that frequency.
The measured performance is typical of that sort of implementation, competent but looks well short of a PuRifi400 or nCore400.
They claim better efficiency in the output but don't explain much about why, perhaps @DonH56 can expand on his comment?
A pity there's not more educational information in the paper to justify the, admittedly small, inconvenience that you can't just read it, have to fill in details and email.

Best wishes
David

 

[restorer-john]

Aren't Panasonic using these in their latest Reference power amplifier?

edit: https://www.technics.com/us/products/r1/se-r1.html

 

[joenetic]

Switching frequency should be 10Mhz according to the data sheet, please correct me if I am wrong.

 

[DonH56]

Switching frequency should be 10Mhz according to the data sheet, please correct me if I am wrong.

I have not been following this thread, sorry (way too busy at work lately). I do not see that (10 MHz switching) anywhere? The TI driver they are using is only good to a few MHz (and does not appear to be optimized for audio, which probably explains the relatively power distortion specs of the kit). The GaN power devices are designed for high voltage, low on-resistance, and (relatively) low charge storage. The high voltage usually means lower switching rates, though plenty high enough for audio, GaN devices offer less loss (charge storage and channel resistance) than conventional devices, though arguably SiC would work as well. This amp uses GaN HEMT devices (high electron-mobility transistors). A lot of switching power supplies are using them now; they appear to be edging out SiC though from my quasi-layman's perspective I am not sure one is all that much better than another in these applications. My experience with HEMT's is at much higher frequencies (and much lower voltage, natch) so I can't say a lot about their use in low-frequency power circuits. And my expertise, such as it is, has strayed from device physics -- last time I delved deeply into that was to develop some SiGe models and give a couple of papers at some gov't and industry conferences. The RF/mW/mmW industry, not audio... That was the mid-1990's, hard to believe.

 

[joenetic]

Thanks guy, I am wrong, 10Mhz is the description of switching frequency of the gan fet I think, not the MCU output switching frequency.

Anyway ganfet has shorter dead time compare to mosfet, expecting some reviews.

 

[Lord Victor]

Has anyone had the chance to try this board, or look closer into it? Curious about the future of GaN fet based amps...

 

[DonH56]

Another article on GaN. Lower Ron is a biggie for less loss, less heat, etc.

https://www.electronicdesign.com/po...da|9938I0589789A1T&oly_enc_id=9938I0589789A1T

 

[restorer-john]

Another article on GaN. Lower Ron is a biggie for less loss, less heat, etc.

https://www.electronicdesign.com/power-management/whitepaper/21170407/its-time-to-get-gan-in-your-power-adapters?utm_source=EG ED Analog & Power Source&utm_medium=email&utm_campaign=CPS210715094&o_eid=9938I0589789A1T&rdx.ident[pull]=omeda|9938I0589789A1T&oly_enc_id=9938I0589789A1T

I reckon the next Purifi (if there is one) will be a high power GaN module.

It'll be funny to watch how fast diehard proponents of current Purifi designs will suddenly jump ship and embrace GaN as the bee's knees, with its extended FR, lower losses etc.

 

[DonH56]

I reckon the next Purifi (if there is one) will be a high power GaN module.

It'll be funny to watch how fast diehard proponents of current Purifi designs will suddenly jump ship and embrace GaN as the bee's knees, with its extended FR, lower losses etc.

I am sure that you, of all folk, are a charter member of the Transistor of the Month club... (Not!)

 

[amirm]

Has anyone had the chance to try this board, or look closer into it? Curious about the future of GaN fet based amps...

Yes, I reviewed and measured it recently: https://www.audiosciencereview.com/...tems-amplifier-eval-board-measurements.24202/