Wha'ts the world's biggest transistor? - Page 1
Forum section: electronics / projects

author: Fried Chicken
author_rank: Regular Contributor
timestamp: March 25, 2024, 04:58:37 am
content: Let's say I wanted to control a lawnmower motor with a transistor... What's the world's biggest transistor? I know power amplifiers have some big transistors, but what if we get into the stupid range?

author: T3sl4co1l
author_rank: Super Contributor
timestamp: March 25, 2024, 05:08:57 am
content: Well they run cars with 'em so it better be a pretty damn big lawn mower!Biggest are in the range of 4kV 2kA, for industrial motor drives and other power conversion applications. Give or take whether you count just IGBTs, or include SCRs as well (theytransist, but not in as straightforward a manner as IGBTs do). The biggest of any semiconductors are SCRs, pushing more like 7kV, 4kA, or probably more, I haven't checked in a while.HVDC links are probably the most powerful monolithic application; with power ratings in the GW, they're constructed from stacks of semiconductors, I think usually SCRs or GCTs.I'm not sure offhand if IGBT modules of that size are made from whole wafers, or many smaller dies in parallel. It does tend to be difficult to use large dies, over 2cm or so, due to differential thermal expansion between the chip and mounting base (typically Cu and AlN). The "puck" modules get around this by sandwiching the die between molybdenum pads, which has similar expansion rate, but the sandwich versus a metallurgical bond (I think, unless they are soldered or otherwise bonded as well; I forget) relieves thermal stress, permitting quite large dies to be used (~whole wafer).Tim

author: Smokey
author_rank: Super Contributor
timestamp: March 25, 2024, 05:28:39 am
content: Quote from: T3sl4co1l on March 25, 2024, 05:08:57 am...All the big modules I've seen are in parallel.

author: Fried Chicken
author_rank: Regular Contributor
timestamp: March 25, 2024, 05:46:19 am
content: Quote from: T3sl4co1l on March 25, 2024, 05:08:57 amWhat is IGBT, SCR, HVDC, Cu (copper), AIN?What do they look like? How much do they cost? Where do you buy them? What drive them, 0.7v? lol

author: ArdWar
author_rank: Frequent Contributor
timestamp: March 25, 2024, 08:55:57 am
content: FWIW you don't need world's biggest transistor to drive a lawnmower motor.Not even close.

author: tggzzz
author_rank: Super Contributor
timestamp: March 25, 2024, 09:20:13 am
content: Quote from: ArdWar on March 25, 2024, 08:55:57 amQuite.I'd start by looking at HVDC power transmission systems, subsea and otherwise. Consider, for example...Today the HVDC power transmission technology is developing at fast pace permitting transfer oflarge quantities of electrical power from big capacity power plants, mainly hydro, to big consumerregions across hundreds or thousands of kilometres. The latest examples of such projects includethe overhead Xiangjiaba-Shanghai interconnector in China and the Rio Madeira HVDC system inBrazil. The Xiangjiaba-Shanghai line is the world’s first UHVDC connection.It operates at ±800 kVand transfers 7200 MWfrom the Xiangjiaba hydropower plant in southwest China to Shanghai,which is 2000 km further away. It is a single overhead line. The losses are rated at less than 7%.The Rio Madeira HVDC system is the longest transmission link in the world. It carries6300 MWfrom new hydro power plants on the Madeira River (Porto Velho) to urban centres in south-easternBrazil over 2375 km, operating at600 kV.https://electrical-engineering-portal.com/res3/HVDC-Submarine-Power-Cables-in-the-World.pdfHVDC Submarine Power Cables in the WorldThat contains alotof interesting information, e.g. thatplanned1.4GW cables havepaperinsulation, weight 60kg/m and have a diameter of 150mm.

author: jonpaul
author_rank: Super Contributor
timestamp: March 25, 2024, 10:44:15 am
content: deend on application, and freq, and def of transistor.eg thyristor, IGBT, SiC, etcfor mains power control ? SMPS? Lighting? power T&D? Industrual control?j

author: tggzzz
author_rank: Super Contributor
timestamp: March 25, 2024, 10:54:38 am
content: Quote from: jonpaul on March 25, 2024, 10:44:15 amThe OP's question is, of course, malformed - so any answer is mootNonetheless some of the irrelevant answers have been moderately interesting.IMHO the biggest transistor is likely to be a naked-silicon 2N2222/BC108/etc packaged in a 19" rack case.

author: SeanB
author_rank: Super Contributor
timestamp: March 25, 2024, 11:13:06 am
content: I have some BUX 20 transistors, which are about the biggest die you can fit into a TO3 package. Have taken apart some industrial transistor arrays, which are made up of a dozen smaller dies, about 1cm by 1cm, that are bonded with lots of bond wires for the emitter to a busbar, and with a common collector plate on an aluminia insulator, allowing them to be rated for up to 1000A at 100V, and with a last die used to drive the rest all in parallel, along with an equal number of diodes clamping reverse spikes on the main transistors. Gain of around 100 at 1000A emitter current, and with a heatsink that had to handle 2kW of power dissipation at that level.The MOSFET replacement modules dissipate 100W for the same power level.....

author: Zero999
author_rank: Super Contributor
timestamp: March 25, 2024, 11:16:33 am
content: Quote from: Fried Chicken on March 25, 2024, 05:46:19 amA search engine is your friend.Start again. What are you trying to do? How many amps and volts does your lawn mower motor use? Is it AC (mains) or DC from a battery? Is it being repurposed i.e. in a lathe or e go-kart project? It doesn't sound like a beginner friendly project.

author: tggzzz
author_rank: Super Contributor
timestamp: March 25, 2024, 12:17:00 pm
content: Quote from: Zero999 on March 25, 2024, 11:16:33 amSee the OP's posting history!

author: Xena E
author_rank: Frequent Contributor
timestamp: March 25, 2024, 01:51:32 pm
content: My lawnmower uses a switch!Irrelevant enough for you?

author: coppice
author_rank: Super Contributor
timestamp: March 25, 2024, 01:55:57 pm
content: Quote from: T3sl4co1l on March 25, 2024, 05:08:57 amI've seen power people referring to 50kA SCRs.

author: Clear as mud
author_rank: Regular Contributor
timestamp: March 25, 2024, 02:00:12 pm
content: Quote from: Fried Chicken on March 25, 2024, 05:46:19 amIGBT and SCR are special types of transistors, normally used in high-power situations. IGBT is insulated gate bipolar transistor, and SCR is silicon controlled rectifier. See Wikipedia or a primer on different types of transistors.HVDC is high voltage direct current. The last few decades as transistor technology has advanced, it has become possible and economical to use DC for power transmission lines instead of AC. In the past, AC was always used because the voltage can be easily changed using a transformer, increased for transmission over long distances, and then decreased for distribution and utilization. But the losses are higher along an AC transmission line. The longer the distance you try to transmit a lot of power, the higher the losses. So, HVDC is now used for long-distance power transmission.AlN is aluminum nitride. I didn't look it up, but it must be a non-conductive solid or a semiconductor.Quote from: Fried Chicken on March 25, 2024, 05:46:19 amI did an image search for "HVDC transistors."Here is a picture of what one IGBT module looks like:https://eepower.com/news/mitsubishi-electric-launching-voltage-source-converters-for-global-hvdc-market/And on this page is a picture of a whole installation at a power transmission station:https://blog.faradars.org/hvdc-%DA%86%DB%8C%D8%B3%D8%AA/.

author: JohanH
author_rank: Frequent Contributor
timestamp: March 25, 2024, 02:28:16 pm
content: HVDC submarine cables use the sea as one conductor! So they are able to use only one cable. The sea has almost negligible resistance. DC cable losses are only 0.3-0.4% per 100 km.https://library.e.abb.com/public/d4863a9b0f77b74ec1257b0c00552758/HVDC%20Cable%20Transmission.pdf

author: Zero999
author_rank: Super Contributor
timestamp: March 25, 2024, 02:46:04 pm
content: Quote from: Xena E on March 25, 2024, 01:51:32 pmInterestingly, I've seen a vacuum cleaner with a foot switch which too small to directly switch the motor, so it switches the gate of a TRIAC, which switches the motor.

author: schmitt trigger
author_rank: Super Contributor
timestamp: March 25, 2024, 03:22:19 pm
content: A Siemens Energy brochure mentions thyristors with a 6” wafer size! Capable of switching 6.5 kA.It also mentions that early 1970s technology required about 28 thousand thyristors per gigawatt for both valve halls. Nowadays this has been reduced to about 600 thyristors per gigawatt. This is an amazing power handling improvement.It only shows a low resolution image of the thyristor, but imagine 3 individual-sized pizzas stacked vertically, and you have an idea of its size.

author: tggzzz
author_rank: Super Contributor
timestamp: March 25, 2024, 03:37:28 pm
content: Quote from: JohanH on March 25, 2024, 02:28:16 pmNot necessarily; some parts of the sea are less saline than others, and metal corrosion can be a problem. See section 2.3.2 "HVDC Configurations" in the report in my reply #5.

author: Fried Chicken
author_rank: Regular Contributor
timestamp: March 25, 2024, 03:49:27 pm
content: Quote from: Zero999Find out what the world's biggest transistor is. If it even is a transistor in the traditional sense.

author: Xena E
author_rank: Frequent Contributor
timestamp: March 25, 2024, 03:50:25 pm
content: Quote from: Zero999 on March 25, 2024, 02:46:04 pmI guess the day when a mechanical switch capable of switching at KW levels of power is cheaper than a smaller one of a few Watts rating plus a semiconductor is long gone.The lawn mower incidentally is a 24 volt battery job and the charger for the gel cells is far more technically advanced than the machine itself... though the pass element in that is incorporated in one of those little 7 pin dil switcher chips, so even that doesn't come close to the OP's requirement to run his electric combined harvester

author: nali
author_rank: Frequent Contributor
timestamp: March 25, 2024, 03:57:05 pm
content: Quote from: Fried Chicken on March 25, 2024, 03:49:27 pmHere you go... Google is your friendhttps://www.atlasobscura.com/places/bell-laboratories-transistor-water-tower

author: Zero999
author_rank: Super Contributor
timestamp: March 25, 2024, 04:26:38 pm
content: Quote from: Fried Chicken on March 25, 2024, 03:49:27 pmAnd what the heck does that have to do with a lawn mower motor?Quote from: Fried Chicken on March 25, 2024, 04:58:37 am

author: Fried Chicken
author_rank: Regular Contributor
timestamp: March 25, 2024, 04:40:47 pm
content: Quote from: Zero999 on March 25, 2024, 04:26:38 pmI guess I should have explained... I was looking at someone building a lawnmower, and I wasn't sure transistors even got large enough to conceivably do that, so I thought a lawnmower was a ridiculous application for a transistor, like you would use something else to power it. Turns out that's not the case, and transistors get quite large.

author: Zero999
author_rank: Super Contributor
timestamp: March 25, 2024, 07:06:53 pm
content: Quote from: Fried Chicken on March 25, 2024, 04:40:47 pmYou were quite mistaken. There are transistors capable of switching far greater loads than a lawn mower motor, which is a fairly small in the scheme of things.You received some irrelevant replies because you didn't say exactly what you're doing. What's the world's biggest transistor? is a meaningless question. Are you talking about physical size, current rating, voltage rating, power dissipation?I had a quick look through Digi Key and found some transistors which are more than capable of switching a lawn mower motor. As you made no mention of voltage, or whether it's DC or AC, I assumed smoothened DC, from a bridge rectifier powering a universal motor, drawing around 1kW or so.https://www.digikey.co.uk/en/products/detail/stmicroelectronics/STP45N40DM2AG/5724369https://www.st.com/content/ccc/resource/technical/document/datasheet/ff/da/51/30/5f/70/4e/77/DM00213649.pdf/files/DM00213649.pdf/jcr:content/translations/en.DM00213649.pdfhttps://www.digikey.co.uk/en/products/detail/infineon-technologies/IRFR4620TRLPBF/2021282https://www.infineon.com/dgdl/irfr4620pbf.pdf?fileId=5546d462533600a4015356323ae920f7They're not that expensive considering. Anther option is to use thyristors for part of the bridge rectifier, which would probably be cheaper but not so flexible.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: March 25, 2024, 07:24:50 pm
content: Quote from: coppice on March 25, 2024, 01:55:57 pmOnly for surge ratings I think. Like you can use a 3-4" puck for quarter shrinker application, though it doesn't perform quite as well as an ignitron, or contactor (preferably explosively-actuated). Those are typically 2-4kA I think, RMS, and about 50kA surge.Does stand to reason that, if they're making them of 12" wafers instead of 3, they can handle a good 16 times more RMS. Probably less actually, because it'll be harder to cool, especially in a stack, but, practical versus device limitations being what they are...Tim

author: ejeffrey
author_rank: Super Contributor
timestamp: March 25, 2024, 08:18:31 pm
content: Quote from: Fried Chicken on March 25, 2024, 04:40:47 pmThe really large devices are just banks of transistors in parallel and/or series for more current and voltage handling. I don't know what the largest single die transtor is but once you can stack them you can basically make any size you want and the cost is mostly linear.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: March 25, 2024, 09:02:26 pm
content: IGBT dies are typically a couple hundred amperes; if scaling keeps up for the higher rated ones, I would guess 6kV ones are rated... maybe pretty low like 50 or 100A, and also as big as dies can get (20, maaaaybe 30mm?), and then stacked in parallel in modules.Oh here we go, actual dice:https://www.5scomponents.com/pdf/Chip-Flyer_0409_Web.pdfso you can see what ratings and dimensions are like. Smaller than I thought.Mind, there may be bigger ones out there; this should be read as a typical example. For further reading you could well contact Infineon, ABB or others and see if they'll entertain your curiosity.90%+ of the finished unit is packaging, necessary to array chips together, dissipate heat, and insulate between them at such voltages where a spark can jump several mm through air already. Sometimes the best insulation is simply distance.---There are also SiC products available, and coming out, in various ratings; I don't think they're quite advanced enough with it to be taking over this kind of power range -- it's devilishly difficult to make low-defect SiC wafers, limiting scalability per cost -- but I have seen papers on 10-12kV MOSFETs and IGBTs in SiC. They are not generally available, I think probably because of ITAR? (They're much faster than Si parts, so you can make a wicked EMP generator with them, or perhaps initiate explosives, etc..)Tim

author: Fried Chicken
author_rank: Regular Contributor
timestamp: March 25, 2024, 11:36:43 pm
content: Quote from: Zero999 on March 25, 2024, 07:06:53 pmThose look tiny for the power they are rated for.I had some idea that production errors or something made larger transistors impossible or very difficult/expensive. I guess not. Just add silicon.

author: Wolfram
author_rank: Frequent Contributor
timestamp: March 26, 2024, 12:18:54 am
content: If you disqualify multi-die parts like the most common IGBT modules, and SCRs which can't be gated off, the most powerful single-die transistors I know of are IGCTs like this one:https://library.e.abb.com/public/0545534831d6421cb2d188bb713661ae/5SHY%2065L4521_5SYA1261-01%20Sep%2020.pdfOne interesting aspect of these is that the gate drive current is as large as or larger than the commutated current, so in the high thousands of amps. This is the reason for the tight integration of the driver with symmetrical planar busbars (Lstray less than 2 nH typically) and the large bank of electrolytics on the driver board.There are also some pretty big presspack IGBTs available these days:https://www.infineon.com/dgdl/Infineon-P3000ZL45X168-DataSheet-v03_00-EN.pdf

author: T3sl4co1l
author_rank: Super Contributor
timestamp: March 26, 2024, 01:44:01 am
content: Hmm, doesn't work. Oh-- leave the ?fileId on there, it's part of the link:https://www.infineon.com/dgdl/Infineon-P3000ZL45X168-DataSheet-v03_00-EN.pdf?fileId=8ac78c8c7f2a768a017facf5116e40b2

author: NiHaoMike
author_rank: Super Contributor
timestamp: March 26, 2024, 03:39:32 am
content: Quote from: Zero999 on March 25, 2024, 07:06:53 pmAren't the modern BLDC mowers only on the order of 300-400W? Not even that big by consumer equipment standards, similar to a Walmart special hybrid bicycle motor. (And a good hybrid bicycle goes well into the kW range!)

author: coppercone2
author_rank: Super Contributor
timestamp: March 26, 2024, 04:32:03 am
content: I don't like all this parallel crap someone needs to go out there and make a giant single transistor

author: Fried Chicken
author_rank: Regular Contributor
timestamp: March 26, 2024, 04:53:59 am
content: Quote from: NiHaoMike on March 26, 2024, 03:39:32 amHe's right, I was completely mistaken... hence why I made this post lol.The biggest transistors I've encountered are audio transistors, and often they're distributed across like 10 of them for a 250wpc amplifier or something.But I have no clue, I'm not an electronics guy. I thought there would be some limit having to do with the purity of silicon manufacturing or something, similar to binning CPUs. There also aren't many youtube torture tests of massive transistors, unlike other electric components.... like the 5000 amp fuse that guy popped lol

author: T3sl4co1l
author_rank: Super Contributor
timestamp: March 26, 2024, 05:42:23 am
content: Heh, well the first problem with (linear) audio amps is power dissipation. You need a ton of metal to carry that heat out. If you don't dissipate it in the first place, you need less silicon (though, not wildly so), and get more output for given input -- efficiency goes way up. Hence, class D amps.The actual chips used inside those amplifier transistors, is pretty small -- a few mm on a side -- again, packaging dominates overall component size -- it's just bringing all that heat out to the air that's the hard part. Switching power supplies avoid that by dissipating full power for extremely small moments in time, averaging low power overall.Tim

author: Zero999
author_rank: Super Contributor
timestamp: March 26, 2024, 09:21:42 am
content: Quote from: Fried Chicken on March 25, 2024, 11:36:43 pmWhilst it's true manufactures often exaggerate when it comes to power ratings, a transistor doesn't have to be that big, to switch a relatively large motor. Remember most of the power goes to the motor. The amount of power lost in the transistor should be as little as possible.Take the STP45N40DM2AG I linked to in my previous post.https://www.st.com/content/ccc/resource/technical/document/datasheet/ff/da/51/30/5f/70/4e/77/DM00213649.pdf/files/DM00213649.pdf/jcr:content/translations/en.DM00213649.pdfSuppose you use it to switch a 2400W motor, running off 240V at 10A. Calculate the power lost in the transistor.According to the data sheet, it has an on resistance of 0.072Ω.P = I2R = 102*0.072 = 100*0.072 = 7.2WOh, that's a little optimistic, reading down the data sheet, it also says the on resistance increases with temperature and it's specified at 25°C, but that's no good, since it's going to be near hot motor. Assuming the transistor might get very hot, say 125°C, the on resistance and thus the power loss will double. Refer to the graph Figure 10 Normalized on-resistance vs temperature on page 7 of the data sheet.P = 14.4WA heat sink is used to dissipate the power lost in the transistor, which is normally much larger than the transistor.According to the transistor's data sheet, it has a thermal resistance of 0.5°C/W. This means for every W of power dissipated the temperature of the transistor itself, inside the case will increase by half a degree, when on a perfect heat sink. The maximum operating temperature of 150°C, but it's never a good idea to work at the maximum temperature and the power losses increase, so lets limit it to 125°C. Assuming it needs to work on a hot day, next to a hot motor, say an ambient temperature of 65°C.Maximum temperature riseTr= Tmax- Tambient= 125-65 = 60°CMaximum thermal resistance to ambientTR = Tr/Pd= 60/14.4W = 4.17°C/WThe thermal resistance of the transistor is 0.5°C/W so that needs to be subtracted.4.17-0.5 = 3.67°C/W.So your heat sink needs to have a lower thermal resistance than that.

author: shapirus
author_rank: Super Contributor
timestamp: March 26, 2024, 11:20:58 am
content: Meh.Connecting devices in parallel is cheating, it's not interesting.Let's rephrase the question this way:what is the world's highest power-rated single-die BJT?

author: NiHaoMike
author_rank: Super Contributor
timestamp: March 26, 2024, 12:22:13 pm
content: Quote from: Fried Chicken on March 26, 2024, 04:53:59 amModern ones use much less silicon, TI does 600W on a chip the size of a sunflower seed! (As far as I'm aware, that's still the record for a single chip amplifier, anything bigger actually has multiple chips inside the module.)QuoteTest of a Prius inverter assembly:

author: T3sl4co1l
author_rank: Super Contributor
timestamp: March 26, 2024, 12:35:51 pm
content: Quote from: shapirus on March 26, 2024, 11:20:58 amNot much, considering they're obsolete for power applicationsBack in the heyday, I suppose one of those 100A+ triple darlington types would've been up there. No SOA to speak of though; switching application.Tim

author: CaptDon
author_rank: Super Contributor
timestamp: March 26, 2024, 01:26:40 pm
content: Just an experience observation from the speak of IGBT's and such. Our older AC4400 locomotives used G.T.O. technology in the inverter stacks. Gate Turn Off had a lot of drawbacks for high power inverters that were being switched at various loads and frequencies. It was hard to optomize for such a broad operating range. When we switched to IGBT's life got less complicated. Early on we had incredibly destructive shoot-through blowouts. If you can imagine 12 capacitors 1700uf@2.5Kv all charged to around 1400vdc and being fed from a 4500 h.p. output alternator with the rotating mass of the crankshaft and alternator weighing in at around 40,000 pounds and suddenly feeding a shoot-through dead short!!! Far worse was when one of the oil filled capacitors went dead short!!!! That particular field failure would blow the aux cab doors right off the locomotive and set the insides of the aux cab on fire with burning oil vapors. Our IGBT drivers had to have various fail-safe interlocking to insure one side of the half bridge could not be commanded on until the other side was tested to be off and that off condition included a dead-time timeout. There are six IGBT's per inverter stack and each IGBT is about 6X9 inches although internally consist of dozens of individual power 'transistors'.

author: Zero999
author_rank: Super Contributor
timestamp: March 26, 2024, 02:25:25 pm
content: Quote from: shapirus on March 26, 2024, 11:20:58 amIf the dies were all manufactured on the same wafer and have good thermal and electrical connections, i.e. mounted in the same package, then there's not much difference between a large single die and many small ones. A large die still has the problems associated with non-uniform construction, due to imperfections in the process and one part heating more than the other, causing its characteristics to be different to the rest.

author: shapirus
author_rank: Super Contributor
timestamp: March 26, 2024, 02:38:37 pm
content: Quote from: Zero999 on March 26, 2024, 02:25:25 pmYeah, the reasons why parallelling multiple smaller dies has practical advantages and is the way to go for mass production are clear. And that is precisely what directs one's curiosity to the largest single-die devices. It might be a one-off product made for a specific application, an experiment, or whatever that's not as boring as mass-produced stuff to be used in everyday life.

author: Fried Chicken
author_rank: Regular Contributor
timestamp: March 26, 2024, 03:18:30 pm
content: Quote from: Zero999 on March 26, 2024, 09:21:42 amWhilst it's true manufactures often exaggerate when it comes to power ratings, a transistor doesn't have to be that big, to switch a relatively large motor. Remember most of the power goes to the motor. The amount of power lost in the transistor should be as little as possible.Take the STP45N40DM2AG I linked to in my previous post.https://www.st.com/content/ccc/resource/technical/document/datasheet/ff/da/51/30/5f/70/4e/77/DM00213649.pdf/files/DM00213649.pdf/jcr:content/translations/en.DM00213649.pdfSuppose you use it to switch a 2400W motor, running off 240V at 10A. Calculate the power lost in the transistor.According to the data sheet, it has an on resistance of 0.072Ω.P = I2R = 102*0.072 = 100*0.072 = 7.2WOh, that's a little optimistic, reading down the data sheet, it also says the on resistance increases with temperature and it's specified at 25°C, but that's no good, since it's going to be near hot motor. Assuming the transistor might get very hot, say 125°C, the on resistance and thus the power loss will double. Refer to the graph Figure 10 Normalized on-resistance vs temperature on page 7 of the data sheet.P = 14.4WA heat sink is used to dissipate the power lost in the transistor, which is normally much larger than the transistor.According to the transistor's data sheet, it has a thermal resistance of 0.5°C/W. This means for every W of power dissipated the temperature of the transistor itself, inside the case will increase by half a degree, when on a perfect heat sink. The maximum operating temperature of 150°C, but it's never a good idea to work at the maximum temperature and the power losses increase, so lets limit it to 125°C. Assuming it needs to work on a hot day, next to a hot motor, say an ambient temperature of 65°C.Maximum temperature riseTr= Tmax- Tambient= 125-65 = 60°CMaximum thermal resistance to ambientTR = Tr/Pd= 60/14.4W = 4.17°C/WThe thermal resistance of the transistor is 0.5°C/W so that needs to be subtracted.4.17-0.5 = 3.67°C/W.So your heat sink needs to have a lower thermal resistance than that.So the gate voltage on one of these, Vgs is +/- 25v, and the threhsold is from 3-5v? So you would need up to 25 volts to drive this transistor?I think it's finally clicked with me how a transistor works... it breaks the rules of electrical circuits. This was never taught in schools b/c nobody actually knows anything about them.

author: Zero999
author_rank: Super Contributor
timestamp: March 26, 2024, 03:36:11 pm
content: Quote from: Fried Chicken on March 26, 2024, 03:18:30 pmNo.The on resistance is specified at different gate drive voltages. 25V is just the maximum rating. Read the data sheet.QuoteNo.A transistor doesn't beak and rules. Why do you believe this to be the case?

author: Fried Chicken
author_rank: Regular Contributor
timestamp: March 26, 2024, 07:28:26 pm
content: Quote from: Zero999 on March 26, 2024, 03:36:11 pmWell it doesn't follow the rules of a traditional circuit. Same with Op-Amps

author: MarkT
author_rank: Frequent Contributor
timestamp: March 26, 2024, 07:31:02 pm
content: Quote from: Clear as mud on March 25, 2024, 02:00:12 pmIn undoped form its a ceramic insulator with extremely good heat-conductivity (though not as good as the very poisonous BeO ceramic). You can make it semiconducting through doping. Its basically a great material for heatsinking.

author: MarkT
author_rank: Frequent Contributor
timestamp: March 26, 2024, 07:32:26 pm
content: Quote from: coppercone2 on March 26, 2024, 04:32:03 amWell there are some nice large thyristors (SCRs) like:https://www.infineon.com/dgdl/Infineon-T2600N-DataSheet-v03_01-EN.pdf?fileId=5546d46277fc7439017836a6f5ff7deb, basically a 65mm wafer in a hockey-puck package.

author: Vovk_Z
author_rank: Super Contributor
timestamp: March 26, 2024, 08:11:26 pm
content: Quote from: tggzzz on March 25, 2024, 09:20:13 am7200 MW?Will it fit my Civic? (c)

author: tggzzz
author_rank: Super Contributor
timestamp: March 26, 2024, 08:34:46 pm
content: Quote from: Fried Chicken on March 26, 2024, 07:28:26 pmThere's no such thing as a "traditional circuit"; the only things are electromagnetic fields and their interaction with matter.There are useful models that are based on simplification of those, and which allow easier "higher level" predictions that are valid in some circumstances but not others.One example of that is "Ohm's Law". You occasionally come across people that believe V=IR, for example.

author: tooki
author_rank: Super Contributor
timestamp: March 26, 2024, 09:14:24 pm
content: Quote from: Fried Chicken on March 26, 2024, 07:28:26 pmPlease, explain which rules an op-amp breaks and how it breaks them.