Last night at 10 pm, I tweeted: “600V GaN FET Breakthrough! Transphorm's Carl Blake promises price & delivery info @ APEC! With demos. AFAICT, Transphorm will be first.” That was right after Transphorm posted its release, and after I exchanged emails with Carl, confirming that this was a real product announcement with real pricing and delivery information. Other companies, including IR and EPC may follow suit, but Transphorm is first with a press announcement.
If you want to know how the Transphorm devices are built, last June, Electronic Design’s sister publication, Power Electronics Technology, ran a long article describing how the Transphorm GaN devices work. PET Editor-in-Chief Sam Davis, makes the observation, “They have an interesting way of driving the GaN device.”
Being able to place orders for 600-V GaN devices is news. At last year’s APEC, IR showed data on real 600-V GaN FETs and promised product sometime in 2011, but to date, there have been no new-product announcements. EPC is in its third GaN generation, but doesn’t show any parts rated for more than 200 V on its Website. At last year's APEC, Transphorm, an IBM-funded startup, said this is what they were working on, but made no specific promises at that time.
If you’re new to GaN, its significance is this: GaN devices have low conduction losses, but their major virtue is that they have virtually no switching losses*. This makes switching power supplies that use them hyper-efficient at all load levels. That’s partly due to low losses, partly due to the ability to use much faster clock rates. (Transphorm promises to show one with 99% peak efficiency at APEC.)
The big deal here is the high peak operating voltage. It makes Transphorm’s new parts attractive in electric vehicles, but, we’ll have to see where that goes. Getting back to Transphorm’s funding, what IBM was probably looking for was more efficient power supplies in data centers. That’s a much bigger, higher-m...More