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The power-switch that controls "on" vs "off" needs to be incredibly efficient when you're shoving 200+ kW of energy through it!!

Yeah, when I was working in EVs everything was about reducing losses. Not just for efficiency but because a few percent loss is a LOT of heat.

I ran an inverter at 200kW that was not rated for that. The weak point was actually the DC connector. I didn't find that out the hard way, just looked it up as I was closing in on 600 Amps DC.

BTW I just needed to find 2 values empirically and was unable to because of that DC current. Strange enough I figured running at a lower voltage would reduce max power and I could get my values. Unfortunately half the voltage is half the power but still the same current. Higher speed had similar issues. Project got cancelled before I found that motors limits.

> I'd argue that without modern IGBTs, it'd be impossible to make an electric car today.

Er, everybody switched to SiC MOSFETs, so... definitely not.

> The power-switch that controls "on" vs "off" needs to be incredibly efficient when you're shoving 200+ kW of energy through it!!

Even before SiC became economical, FETs were edging out IGBTs in most applications. The voltage drop across IGBTs is just too high.

In fact SiCs have worse on/off efficiency, but are still preferred because they can switch more quickly and in the end that makes them more efficient, overall.

> Its probably one of the most major sources of efficiency in the modern electric vehicle.

I would give that to the battery or the motors before the controller. Controller have been >97% efficient for ages and ages, but motors are another thing entirely and better computers, salient rotors and permanent magnets, and better characterization have led to bigger gains than the switching elements have seen.

Neither hold a candle to batteries though. The resistance of switches is <10 milliohms, and motor resistance isn't much higher. The resistance of a 400 volt, 250 Ah NiMH battery is around 180 milliohms. The same battery built with venerable NCR18650Bs (original model S) is 68 milliohms. That's a full 7x improvement, or an 86% reduction in loss, and by far the biggest inefficiency besides aerodynamics and rolling friction.

> The resistance of a 400 volt, 250 Ah NiMH battery is around 180 milliohms. The same battery built with venerable NCR18650Bs (original model S) is 68 milliohms. That's a full 7x improvement

Power dissipated by resistance is only linearly (not quadratically) related to resistance when current is relatively fixed: P=(I^2)R. So reducing the parasitic resistance from 180mΩ to 68mΩ is only a 2.6x improvement, albeit still quite significant.

> Er, everybody switched to SiC MOSFETs, so... definitely not.

Definitely not everybody are on SiC parts, let alone MOSFET only designs. Though, the trends is for at least some hybrid SiC parts as they are getting cheaper.

When switching speeds are low enough (as is in EVs,) you don't need that much switching performance. Current Si IGBTs are quite viable in EVs, if you switch high enough voltage.

There is a reason why rail is still preferring high voltage AC for traction. That's because Si IGBTs for that are cheap, and efficient enough.

My bull case on CREE was their silicon-carbide rectifier tech was important for power supplies, but I can tell you without even glancing at the chart that CREE is not trading at an all-time high :=)

I always thought of ADI as a company with ASICs like PLLs and MEMS and whatever. Are IGBT drivers an important line of business for them (I don't follow the company closely).

If you look at another company that makes a shitload of power semiconductors, like Infineon, they are struggling.

> I always thought of ADI as a company with ASICs like PLLs and MEMS and whatever. Are IGBT drivers an important line of business for them (I don't follow the company closely).

IGBTs were more of a TI-comment. I see TI as more of the power-company.

I like talking about IGBTs because its superficially a simple subject. It just a switch: power turns on, power turns off. But when you really consider the shear level of efficiency being developed today, its mind-boggling.

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You're right that I don't see ADI as an IGBT (or similar) company. But I just sorta went on a tangent, hooking into your TI-comment more so than ADI.

I think it's AD/DA conversion product lines that are really driving profitability - and I suspect mainly the RF stuff.

You should look again. CREE is very near all time highs actually (especially if you ignore the 2000 bubble).

CREE is a large but shrinking LED business tied to a small but growing SiC business. At some point the SiC part will overshadow the LED part and CREE will be seen as a growing successful tech company again.