What do you call a non-Schottky diode? - Page 1
Forum section: electronics / beginners

author: adx
author_rank: Frequent Contributor
timestamp: June 29, 2024, 12:17:42 pm
content: To differentiate them from Schottkys? Rather than just call them "diode".I've been know to call them "silicon" diodes which is as wrong as the above (or even wronger), I think from a shortening of "silicon junction" (which is probably correct, if long).PN junction (or p-n junction or just PN) diode is convenient if a bit technical (I'd never call a a Schottky a "hot carrier" diode, unless in some RF field (as in, workplace) or back in the 70s). Wikipedia has p-n junction pointing to 'ordinary' diodes on its Schottky page.

author: Gyro
author_rank: Super Contributor
timestamp: June 29, 2024, 12:21:04 pm
content: Diode is fine, Schottky is a qualifier. You could always say signal diode or rectifier diode if you feel it's too short I suppose.

author: rsjsouza
author_rank: Super Contributor
timestamp: June 29, 2024, 12:25:40 pm
content: Indeed. The pre-Schottky solid state diodes were called either "Germanium diode", "Silicon diode", "Selenium diode (or rectifier)" and so on. This is a costumary way to name them.Coming even a bit further back, the diodes from the vacuum tube era were qualified by their function: rectifier diode, damper diode, detector diode and so on.

author: adx
author_rank: Frequent Contributor
timestamp: June 29, 2024, 01:10:28 pm
content: Hmm, maybe I was a bit hard on myself calling "silicon" (or nothing) wrong after all those years - perhaps "all silicon"?! (Or whatever it is made of.)I hadn't thought about the historical aspect(s). Except for the 70s. Perhaps I have become too fearful of ambiguity as I hurtle towards antiquity. Which is rather ironic.There's also PIN diodes, which is a counterexample to my hot carrier example. Once a mate set fire to the carrier of my bike at a party, and when I got home (~5km) it was still on fire! (He'll know who he is.) I was actually down there today, and the charred remains of the plastic left a black scrape against the freshly (few years ago) painted concrete walls that I leaned it on. I felt a small shard of guilt circle my heart until the orbital dynamics slingshotted it off at a great rate of kiloknots (slingschotted?). I digress.Cool, I'll stick with "silicon" or "" I think.

author: tggzzz
author_rank: Super Contributor
timestamp: June 29, 2024, 02:05:53 pm
content: Quote from: adx on June 29, 2024, 12:17:42 pmDiode, optionally plus material.Unless, that is, it is a Gunn, IMPATT, PIN, photo, tunnel, zener, noise, varactor, snap, MIM diodeNow, which types have I forgotten about

author: nfmax
author_rank: Super Contributor
timestamp: June 29, 2024, 02:24:00 pm
content: Try asemiconductor junction diode, to distinguish them from the metal-semiconductor junction of the Schottky diode

author: themadhippy
author_rank: Super Contributor
timestamp: June 29, 2024, 04:30:51 pm
content: Ask the diode what it identifys as

author: magic
author_rank: Super Contributor
timestamp: June 29, 2024, 04:50:21 pm
content: PN diode.Or, if just "silicon diode" bothers you, make it an "ordinary silicon diode".

author: Benta
author_rank: Super Contributor
timestamp: June 29, 2024, 06:25:21 pm
content: Yep, PN diode.

author: MrAl
author_rank: Super Contributor
timestamp: June 29, 2024, 08:35:21 pm
content: Hello,I would think "regular silicon diode" would be ok, but most often we have to qualify the type anyway because of the application it will be used in.For example, you would not use a rectifier diode in a switching converter, and you would not use a high speed diode or zero recovery diode in a mains line rectifier. That's because of the cost vs switching speed. Rectifier diodes are relatively slow because they only have to work at 50 or 60Hz and possibly rarely at 400Hz.Actually, it's almost always better to specify the part number, such as 1N4004 or 1N5402, etc., or 1N5817, etc. That reduces the error of getting the wrong part. I've seen cases where someone tried to use a 1N4001 diode for a switching converter, which is a big no-no.

author: coppercone2
author_rank: Super Contributor
timestamp: June 29, 2024, 08:49:44 pm
content: or say fast diode, low leakage diode, stable diode

author: David Hess
author_rank: Super Contributor
timestamp: June 29, 2024, 09:21:29 pm
content: On my parts drawers I mark them schottky, silicon (low leakage non-gold doped), switching (gold doped), avalanche, zener, etc., but I also have germanium 1N270s to be distinguished.

author: nali
author_rank: Frequent Contributor
timestamp: June 30, 2024, 07:40:24 am
content: Quote from: tggzzz on June 29, 2024, 02:05:53 pmGalena(I suspect you might just be old enough)

author: T3sl4co1l
author_rank: Super Contributor
timestamp: June 30, 2024, 08:00:50 am
content: "PN" or "PN junction". A bit ungainly, but specific, so worth using when that specificity is required. When context allows, "junction diode" or "diode". Or "it" when pronouns will even suffice.Tim

author: Psi
author_rank: Super Contributor
timestamp: June 30, 2024, 08:03:46 am
content: I classify diodes as.- Silicon- Schottky- Germanium- Zener- Fast (This is just a bin for any special/ultra fast diodes that i bought for DCDC stuff)I also have a bin for bridge rectifiers, mainly because they are physically large, so it makes more sense to store them together.

author: adx
author_rank: Frequent Contributor
timestamp: June 30, 2024, 09:33:10 am
content: I have 4 parts drawers marked 1N4004, 1N5819, 1N4148 and BAT85, into which anything can go as long as it's not confusing (ie, a Zener). Another for bridges, another for "SR"s (Schottky rectifiers aka SMPS diodes), and some random round ball types I pulled from some old band printer board I gas torched apart once. EPROMs near the 1N4148s in hindsight possibly because they're glass and you can see the chips inside.The extent of my nomenclature accuracy is probably calling them "diode" and "BAT", along with various colleagues who would say the same things. 'The wider experience' doesn't seem to be much different!I think my recent surprise problem with "silicon" is that most semiconductor diodes are made of that (except LEDs maybe), and similarly for "junction" (unless it has a vacuum, or mercury perhaps). "PN" has a nice alignment with "PIN". "Ordinary" sounds a bit potentially insulting and could make said diode feel upset, assuming the electrical ReLU function gives it enough AI smarts to feel slighted.I think I'm happiest knowing that "not knowing" is kind of universal. So not only do I not need to remember anything, I can forget and be hypothetically happy I don't know!

author: David Hess
author_rank: Super Contributor
timestamp: June 30, 2024, 02:47:06 pm
content: I am currently in the process of renewing my parts cabinets. Shown below are three generations of labeling going back more then 30 years. The oldest are hand written using a technical pen and india ink, the next oldest are drawn in AutoCAD, and the newest are made in Libreoffice Calc.I have 1N458 and FDH300 diodes on order which will be marked silicon, and the 1N4149 will be changed to switching. I will likely change some of the others to silicon rectifier and schottky rectifier.

author: tggzzz
author_rank: Super Contributor
timestamp: June 30, 2024, 08:11:12 pm
content: Quote from: nali on June 30, 2024, 07:40:24 am...selenium, crystal...

author: CatalinaWOW
author_rank: Super Contributor
timestamp: July 01, 2024, 12:48:45 am
content: The Galena diodes were point contact diodes, as were some early germanium diodes. I don't remember anyone doing point contact silicon diodes.Since the vast majority of diodes encountered over the last 50 years are silicon junction diodes, with schottky a distant second, I find diode a valid shorthand. When another type is discussed add appropriate qualifiers.

author: TimFox
author_rank: Super Contributor
timestamp: July 01, 2024, 01:13:34 am
content: The 1N21 series of radar detector diodes are silicon point-contact devices.

author: Circlotron
author_rank: Super Contributor
timestamp: July 01, 2024, 01:40:10 am
content: Could a Schottky diode be made using germanium? And if so, would it have an even lower forward voltage drop than a normal germanium diode?

author: MLXXXp
author_rank: Frequent Contributor
timestamp: July 01, 2024, 01:49:08 am
content: Quote from: tggzzz on June 29, 2024, 02:05:53 pmLight emitting.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: July 01, 2024, 04:24:28 am
content: Quote from: Circlotron on July 01, 2024, 01:40:10 amYes. Depending on how a whisker diode is made, it may happen. Though I think they way they made e.g. 1N34 was by fusing the whisker in place, with attendant doping effect (driven by plating applied to the whisker..?), which made a PN junction, just a very small (and fast) one.Tim

author: MrAl
author_rank: Super Contributor
timestamp: July 01, 2024, 12:24:00 pm
content: Hello,You could make your own point contact diode with a rusty piece of steel sheet metal and a sewing pin. The pin is mounted with an insulator and so the pins point pressure can be adjusted as it contacts the rusty steel. The pin becomes one terminal and the rusty steel the other terminal of the diode. When the pressure is right, it acts like a diode and can be used to demodulate AM radio signals to receive radio frequency transmissions.You may also have to adjust the position where the pins point contacts the rusty metal so it touches it in a 'good' spot where the rust is just right.

author: David Hess
author_rank: Super Contributor
timestamp: July 01, 2024, 01:46:04 pm
content: Quote from: Circlotron on July 01, 2024, 01:40:10 amI remember someone making, or at least announcing, germanium Schottky rectifiers after the MOSFET power semiconductor revolution, but synchronous rectification ended up being a better solution. I suspect the higher leakage and lower operating temperature of a germanium Schottky diode would be too limiting.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: July 01, 2024, 02:32:02 pm
content: I guess I wonder if MOS schottky techniques would do anything employed on Ge, or SiGe for that matter. (On that note, there are some SiGe schottky out there, with incrementally better specs; SiGe is a fairly simple process as things go, AFAIK, so it's not as scary as it sounds.) Mostly, or pure, Ge, the Eg is probably just too low to get reasonable temperature range, even with improvements like MOS.Likewise SiC should be extendable into the some-kV range at good performance, good enough to still be limited by bulk resistivity; not that we'll see (or, frankly (or hopefully?!) need?) it in consumer-industrial applications, but distribution-level and high-power converter or generator applications can benefit.Tim

author: schmitt trigger
author_rank: Super Contributor
timestamp: July 01, 2024, 03:19:30 pm
content: Quote from: tggzzz on June 30, 2024, 08:11:12 pmI am old enough to have worked with Selenium rectifiers. When they let the magic smoke out, it was very nasty. They also had a significant forward voltage drop. If you replaced it with a silicon diode, the B+ voltage would increase. You had to add a series resistor to bring the voltage down.

author: adx
author_rank: Frequent Contributor
timestamp: July 01, 2024, 03:25:22 pm
content: I remember reading an article online where a horse got 'excited' and got a bit rampant upon seeing the Queen in Victorian times (and stuff like that) and in this story it had blue LEDs on a Xmas tree back in the 1800s / 1900s (ah... the ole 1900s), which claimed to be a somewhat accurate account of well it was a bit fanciful. But I checked up on the blue LED thing and lo and behold yes invented (or made) in 1907, by poking at SiC with some wire. So I excitedly (not in the same way as the horse) got some coarse grit sandpaper, wire, and microscope and replicated said poking - much like this...https://commons.wikimedia.org/wiki/File:SiC_LED_historic.jpgIt worked! Greeney or bluey light. Sometimes orange, so I had to rule out the usual reason for orange-emitting things (with smoke). The site was called something like strange science, have not been able to find it since. It was real, honest! (Or I believe it was, or at least believed I believe it was.)Just checked, Infineon have got a 3.3kV SiC fet half bridge. 2.5mR. That's getting quite impressive. Imagine getting a greeney bluey orange light out of that.I also fondly remember pulling selenium rectifiers out of old things. No way, still a current product!

author: T3sl4co1l
author_rank: Super Contributor
timestamp: July 01, 2024, 03:52:07 pm
content: Oh yeah, on that note, I wonder if SiC BJTs light up at all -- and also GaN JFETs (the few that exist out there?), do they glow blue in that narrow band before excessive bias blows up the gate?Tim

author: Wallace Gasiewicz
author_rank: Super Contributor
timestamp: July 02, 2024, 01:04:07 pm
content: I really scared myself once.....I turned on a Kenwood TS 940 with the covers off and saw all the little diodes glowing. I thought I blew the whole thing but the diodes in that thing were meant to glow!Many diodes do glow and the package hides the effect and also shields the diode from light, which may cause changes. Hence light sensitive diodes.

author: jzx
author_rank: Regular Contributor
timestamp: July 02, 2024, 01:15:25 pm
content: I once have seen a led in a glass package similar to the 1n4148. This was in a solar calculator and the diode was used as a zener. I checked with the dmm and then it iluminated.

author: nfmax
author_rank: Super Contributor
timestamp: July 02, 2024, 01:38:52 pm
content: Electroluminescence was first reported in a SiC diode by H J Round - in 1907!https://en.m.wikipedia.org/wiki/H._J._Round

author: Zenith
author_rank: Frequent Contributor
timestamp: July 04, 2024, 09:36:07 am
content: Quote from: tggzzz on June 29, 2024, 02:05:53 pmBackwards diodes.

author: Circlotron
author_rank: Super Contributor
timestamp: July 04, 2024, 12:34:40 pm
content: Quote from: tggzzz on June 29, 2024, 02:05:53 pmShockley diode aka DIAC.

author: madires
author_rank: Super Contributor
timestamp: July 04, 2024, 01:16:57 pm
content: Some more: stabistor, TVS and CLD

author: MrAl
author_rank: Super Contributor
timestamp: July 04, 2024, 06:11:21 pm
content: Quote from: adx on June 29, 2024, 12:17:42 pmHi,As to the title, "What do you call a non-Schottky diode?", the answer is in the question itself.Call it a "non-Schottky diode"

author: David Hess
author_rank: Super Contributor
timestamp: July 05, 2024, 07:34:31 am
content: Quote from: Circlotron on July 04, 2024, 12:34:40 pmA Shockley diode is a 4 layer diode with asymmetrical breakdown. A DIAC is constructed with 4 layers, but also has the implants which would be used for a TRIAC gate, but without the gate connections, making it a low voltage TRIAC without gate connections.Two Shockley diodes in anti-series operate like a DIAC.

author: Gyro
author_rank: Super Contributor
timestamp: July 05, 2024, 08:23:04 am
content: Quote from: Zenith on July 04, 2024, 09:36:07 amAli / ebay / Amazon diodes (there may be some overlap with backwards diodes here).

author: exe
author_rank: Unknown
timestamp: July 05, 2024, 11:45:41 am
content: I think I see the point in differentiation like that. But I'd also say that "PN diode" doesn't tell me much. I differentiate diodes by forward voltage drop (at required current), reverse recovery time, maximum blocking voltage, power rating, leakage and capacitance. Silicon diode, or schottkey or "fast recovery" are too unspecific for me.

author: madires
author_rank: Super Contributor
timestamp: July 05, 2024, 01:06:49 pm
content: And two more: selenium and vacuum tube

author: adx
author_rank: Frequent Contributor
timestamp: July 05, 2024, 02:16:06 pm
content: I notice no one has yet fallen into the trap of "solar cell" (first thing I thought of, lucky I didn't say anything). I then wondered if anyone has ever made (or more likely purchased) a "wooden diode", in the style of cache RAM chips (eBay / backwards diode). Just Googled for "diode connected relay" which it seems no one has typed before in the past 30 years at least (magnetically polarised latching relay which doesn't turn off...).On the subject of that SiC bridge going phooey in greeney bluey orange light (let's say 10kA fault current at 2kV)...embed...(Incidentally from the mate who set my carrier on fire, I was willing it not to go out all the way home - btw I don't remember it as some pyromaniacal escapade, it was more a 'safety feature' owing to no rear bike light now I think about it.)(Looks like link to Shorts not workinghttps://youtube.com/shorts/aIphjOiaiIg)

author: Circlotron
author_rank: Super Contributor
timestamp: July 05, 2024, 11:07:36 pm
content: MOSFET body diode.

author: vk6zgo
author_rank: Super Contributor
timestamp: July 06, 2024, 01:47:27 am
content: Quote from: MrAl on June 29, 2024, 08:35:21 pmThe rectifier diodes used to produce "boost HT"*from the over-wind on Horizontal Output transformers on analog TVs had to operate at 15kHz & were "fast recovery" diodes.Use an ordinary silicon rectifier, like you would use for 50/60 Hz, & it will work,----for about 10 seconds!!*I don't think they were called that on solid state TVs, but I learnt about such over-winds in the tube days.Their purpose was to supply a higher voltage HT for the vertical OP & audio OP stages.

author: Calvin
author_rank: Regular Contributor
timestamp: July 06, 2024, 05:59:29 am
content: Hi,well, seemingly the only correct answer to "What do you call a non-Schottky diode?" must be a ....SchnottkyregardsCalvin

author: David Hess
author_rank: Super Contributor
timestamp: July 06, 2024, 06:57:26 am
content: Quote from: MrAl on June 29, 2024, 08:35:21 pmA Schottky rectifier is sometimes specified for a mains line rectifier for lower voltage drop or to avoid noise from snap back during reverse recovery. Or fast recovery diodes may be specified to also avoid noise from snap back.

author: adx
author_rank: Frequent Contributor
timestamp: July 06, 2024, 02:41:47 pm
content: X-ray tube, CRT.

author: adx
author_rank: Frequent Contributor
timestamp: July 06, 2024, 03:01:07 pm
content: Undecided on a (cavity) magnetron though.

author: Gyro
author_rank: Super Contributor
timestamp: July 06, 2024, 05:03:30 pm
content: Quote from: adx on July 06, 2024, 02:41:47 pmThe CRT is at least a triode (pentode or more depending on whether you count the focus electrodes etc.)

author: Circlotron
author_rank: Super Contributor
timestamp: July 06, 2024, 10:25:49 pm
content: Quote from: Gyro on July 06, 2024, 05:03:30 pmThat would be a project. To get a CRT to function as an amplifier.

author: tggzzz
author_rank: Super Contributor
timestamp: July 06, 2024, 10:31:50 pm
content: Quote from: Gyro on July 06, 2024, 05:03:30 pmCRTs were used as RAM, up to 2560 bits.

author: Gyro
author_rank: Super Contributor
timestamp: July 07, 2024, 10:31:05 am
content: Quote from: Circlotron on July 06, 2024, 10:25:49 pmYou'd have to de-focus the beama lotto get any significant anode dissipation, otherwise you'd generate an internal cloud of Aluminium and phosphor vapor! There are Beam Triodes though, which have a basic electron gun assembly, firing into a cup shaped anode. They were used as high voltage shunt regulators for things like regulating the EHT supply to CRTs in high end monitors to prevent image blooming.

author: David Hess
author_rank: Super Contributor
timestamp: July 07, 2024, 01:00:19 pm
content: Quote from: Gyro on July 07, 2024, 10:31:05 amBeam deflection tubescould be used as amplifiers.

author: adx
author_rank: Frequent Contributor
timestamp: July 07, 2024, 05:11:27 pm
content: Quote from: Gyro on July 06, 2024, 05:03:30 pmI'll wear that one. Bit of a stretch.On the subject of "diodes that have far too many electrodes", there's this thing...