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Re:How do transistors work, anyway? by srvmshr on Tuesday November 29, 2022 @07:58AM (#33787027)
I was disappointed with the article.

This doesn't explain anything that beyond a standard textbook. Same stuff - differently regurgitated. (If you want a swing on this topic MIT 6.004/nand2tetris does a better job & even talks about trade-offs such as doping, channel contaminations, propagation delays due to FET designs, which electrical engineers routinely deal with in production. There are few videos by Carver Mead as well who intuitively explains why transistor work the way they do.)

And for delving into F/R bias, junction effects, leakage current - there are no illustrations showing polarity or flow of charges. Sorry but this is just another low SNR article for today.

Re:How do transistors work, anyway? by mhh__ on Tuesday November 29, 2022 @09:13AM (#33787797)
Bob Widlar also wrote an intro to semiconductors
Re:How do transistors work, anyway? by abfan1127 on Tuesday November 29, 2022 @11:25AM (#33789572)
my undergraduate analog circuits professor worked with Bob Widlar. He had some great stories. Widlar was a pioneer!
Re:How do transistors work, anyway? by gaze on Tuesday November 29, 2022 @12:12PM (#33790246)
It's an extremely underappreciated text
Re:How do transistors work, anyway? by ce4 on Tuesday November 29, 2022 @01:21PM (#33791160)
Re:How do transistors work, anyway? by srvmshr on Tuesday November 29, 2022 @01:30PM (#33791284)
If I could think of anyone being Rick Sanchez (of Rick & Morty) in real life, it had to be Bob Widlar: Brash, extremely genius & mostly drunk.
Re:How do transistors work, anyway? by weinzierl on Tuesday November 29, 2022 @02:34PM (#33792117)
I like how he had his retirement period in the middle of his life and not at the end.

This quote in the section about his retirement in the Wikipedia article made me chuckle:

His proud statement: "I don't work" caused him frequent troubles when crossing the Mexican border and eventually, Widlar created a set of fake business cards presenting him as a "road agent" for "Morgan Associates".

Re:How do transistors work, anyway? by weinzierl on Tuesday November 29, 2022 @11:28AM (#33789612)
Not disappointed, it's a good introductory text with beautiful illustrations. It is called "How do transistors work, anyway?" and not "How do transistors really work?" or "The big transistor deep dive!". I think the article matches the expectations set by the title pretty well.

That is not to say an accessible transistor deep dive would be interesting. I enjoyed my fair share of band gap calculations at university and not to forget Shockley's Garage. That's what an in depth transistor coverage would be for me.

You raised very different points and I would live to read that transistor article anytime.

Re:How do transistors work, anyway? by srvmshr on Tuesday November 29, 2022 @11:43AM (#33789812)
Normally I avoid sounding critical but since you vociferously defend the article's merit, here is what I honestly feel: As people deeply involved or passionate about tech, we hope HN to be a place where

* Read something we know from a different perspective (a.k.a the hacker way)

* Read something deeper which explains the (usually simpler) stuff in due course (i.e. deepdive)

I get it, you love the article and you want it on HN. But it does nothing more than regurgitating what we learned in university already. And the treatment of the topic is pedestrian (Please see why I critiqued it in terms of absence F/R bias & charge flow etc. Just having a sketch of the BJTs & FETs is extremely low bar)

Re:How do transistors work, anyway? by sheusndudn on Tuesday November 29, 2022 @11:55AM (#33790020)
I didn't learn about this in university and was interested by the article. Maybe consider that not everyone took electric engineering and move on with your day?
Re:How do transistors work, anyway? by srvmshr on Tuesday November 29, 2022 @12:18PM (#33790331)
Absolutely. But would you like to base your understanding of something vis a well written, intuitively illustrated article (not necessarily math or physics heavy) or something which is a refined copypasta from any basic electronic textbook?

If I could show you where to find a better place to learn, would you still consider me to "mind my own business"

I am not a knight crusader appointed by HN. But I would be happy if people got a better appreciation of things others love. And that needs some constructive critique at times. And at HN I try to do that whenever I can.

Re:How do transistors work, anyway? by subhro on Tuesday November 29, 2022 @12:33PM (#33790548)
Could you please share the source you mentioned above. Although a computer scientist by profession, I had to "just accept" lots of basic electrical engineer concepts in my undergrad days just because there was no one available that I could ask.
Re:How do transistors work, anyway? by srvmshr on Tuesday November 29, 2022 @12:53PM (#33790789)
For a very quick reference, if you don't know anything:

https://www.digikey.com/en/articles/transistor-basics

And then,

https://youtu.be/qhJaq3kl6Dc https://youtu.be/AnEVas6cl6Y

Someone even mentioned Ben Eater's videos on SC & PN Diodes & P-N-P/N-P-N transistors. I liked those too when I was learning. Finally the first 10-15 pages in Chapter 1 of Milman & Halkias (PDFs widely circulating) are such a clear read, if something still doesn't click.

For the deep dive details I mentioned in parent post, follow 6.004 Computation Structures' first few lectures. Nand2Tetris lectures also cover how circuits are built from these basic units to make functional units of computer (Bonus: they used to have a simulation software with the book which was neat).

This will build a conceptual model of whats going on in these tiny semiconductor bits - unlike other places which throw in a bunch of facts & expect you to build on top of them

Re:How do transistors work, anyway? by cweagans on Tuesday November 29, 2022 @01:31PM (#33791289)
See also https://nandgame.com -- it's not nearly as comprehensive as the nand2tetris simulator, but it's a lot of fun to work through.
Re:How do transistors work, anyway? by itishappy on Tuesday November 29, 2022 @02:14PM (#33791818)
I think the Digikey page is a far worse introduction than the article. It explains what transistors are, but not at all how they work. It doesn't mention what N and P type silicon are, no mention of depletion zone, there are tables filled with PNs before we even get to the word "electron", and the history is fascinating but not particularly illustrative or helpful for how transistors actually work. I think they're intended for different audiences.

I think the article is an excellent introduction to the subject. Maybe the videos explain things better, but I didn't watch them, sorry. I'd much prefer to read a 5m article than 2hrs of video, and I think that's pretty common here. I personally think this fits great on HN.

Edit: Second video was very nice; it's short and sweet and covers the same material as the article. I still prefer the article, but some may prefer the different format.

Re:How do transistors work, anyway? by srvmshr on Tuesday November 29, 2022 @02:34PM (#33792125)
> I think the Digikey page is a far worse introduction than the article.

I started with a disclaimer: If you know nothing - absolute zero. If this was the first time you heard about it. And it does the thing its intended to do i.e. tell a concise history and introducing some of the jargons

To each his own. I think the OP article is pretty poorly written & handwavy. My complaint of not showing charge flow or polarities still holds.

Re:How do transistors work, anyway? by itishappy on Tuesday November 29, 2022 @02:57PM (#33792414)
Completely understood, but still completely disagree. My point is that I feel the DigiKey page is not a good introduction if you're starting from scratch. It barely introduces and doesn't explain any of the jargon. It spends less than 2 paragraphs to cover the material from the article, and includes the same plumbing valve diagram. It doesn't cover what a semiconductor is or what makes them useful. It misses all the information about how/why transistors work and jumps straight to how to design around them.

In other words, the DigiKey page fails to answer the question: How do transistors work, anyway?

Re:How do transistors work, anyway? by srvmshr on Tuesday November 29, 2022 @03:09PM (#33792584)
> In other words, the DigiKey page fails to answer the question: How do transistors work, anyway?

No, it is to first familiarize What is a transistor anyway?.

If I had to teach Complex Analysis, I would start with a calculus refresher. Or if I had to teach Deep learning, I would probably first explain what's a neural network. My recommendation followed a structure. You could even swap out Digikey product description pages for Wikipedia, I couldn't care any less if it just has to introduce what not how. But when it comes to teaching "how the stuff works", anything less than showing biases, polarities & charge flow is a handwave. I am not making arguments for the sake of arguments - if anyone thinks they got it without touching those, they are tricking themselves in.

Re:How do transistors work, anyway? by itishappy on Tuesday November 29, 2022 @03:29PM (#33792830)
That's not the point of this thread though, is it? It asks and answers a very different question. I do not think the history or specs are at all helpful in understanding what makes transistors tick.

"How do tower cranes work?"

"They can carry 20 tons and have a travel of 50 meters and were invented in 1950."

Re:How do transistors work, anyway? by purpleblue on Tuesday November 29, 2022 @11:57AM (#33790051)
You don't have the right to gatekeep on HN. There are plenty of people here that aren't Electrical engineers and the article will be great for them. I certainly enjoyed it. The thing I love about HN is exposure to various types of articles, even things not even remotely related to tech, and certainly YOU should not be some sort of purveyor about what belongs on HN or not.
Re:How do transistors work, anyway? by srvmshr on Tuesday November 29, 2022 @12:08PM (#33790190)
> You don't have the right to gatekeep on HN.

Absolutely not. But I have every right to point out where an article does a lot of handwaving & is plainly shallow.

> There are plenty of people here that aren't Electrical engineers and the article will be great for them.

Neither am I. Thats the best thing about being on HN. People are very passionate about the wave of information & its quality. Also if the SNR of articles weren't high & it was just another Medium, you & I won't be discussing its merits here. Thankfully HN posts manage to attract the curious minds.

> YOU should not be some sort of purveyor about what belongs on HN or not.

I dont. @dang does that. My job is to express my views constructively & debate logically without resorting to emotional barrage. You shouldn't either.

Re:How do transistors work, anyway? by purpleblue on Tuesday November 29, 2022 @03:00PM (#33792453)
>> You don't have the right to gatekeep on HN. >Absolutely not.

Then I suggest you stop. If you don't like an article, then you can skip it. There's nothing worse than people not liking an article and then decrying about it on the comments when all they need to do is move onto the next article.

Re:How do transistors work, anyway? by srvmshr on Tuesday November 29, 2022 @03:18PM (#33792676)
"And who should you be to command me that, Mi'lord?"

You are guilty of the very things you _presume_ I am doing: Gatekeeping. I have as much entitlement to expressing myself, as you, on this site if I am doing a constructive discussion. You don't like my critique of the post? Then move on - just like you suggest. Not my suggestion but yours

Trolling me is such a wasteful spending of your time. Better would be to mind your own business instead of telling me what topics I am allowed to post or not.

Re:How do transistors work, anyway? by purpleblue on Tuesday November 29, 2022 @07:14PM (#33795216)
Telling someone to stop gatekeeping is not gatekeeping.
Re:How do transistors work, anyway? by slingnow on Tuesday November 29, 2022 @01:02PM (#33790924)
Serious question: you consider rectangles with crosshatching "beautiful illustrations"?

I completely agree with the OP. This is a _pure_ regurgitation of introductory material one could find anywhere. The internet is overflowing with this exact description of how a transistor works.

I'm not an EE, but from time-to-time I dabble with electronics. When curiosity gets the best of me I go looking for articles about how transistors work. They all look like this one. What makes this disappointing is that the author sets up the article like they are about to wow you with their particularly special insight into the topic, but proceeds to copy paste the explanation from a textbook.

Re:How do transistors work, anyway? by itishappy on Tuesday November 29, 2022 @04:13PM (#33793387)
> Serious question: you consider rectangles with crosshatching "beautiful illustrations"?

Yeah, particularly compared to everything else mentioned so far in this thread (with the possible exception of the YouTube videos I have not investigated).

> This is a pure regurgitation of introductory material one could find anywhere.

Can you share a better presentation of this material? The current suggestions include a full MIT course, a pair of 2 hour long lectures, "the book from the class we all took in college," and the Wikipedia page for transistors, all of which feel like they're targeting very different audiences than a short illustrated article such as this. Ben Eater's vids are great and a lot closer in scope, but YouTube is very different format and many (such as myself) prefer reading.

Re:How do transistors work, anyway? by srvmshr on Tuesday November 29, 2022 @04:45PM (#33793787)
Since you asked again:

1. https://www.build-electronic-circuits.com/how-transistors-wo...

2. https://www.learnabout-electronics.org/Semiconductors/bjt_03...

> The current suggestions include a full MIT course, a pair of 2 hour long lectures, "the book from the class we all took in college," and the Wikipedia page for transistors,

You have taken my other set of answer out of context: In case you missed the text, I mentioned first couple of lectures of 6.004 (probably 2nd & 3rd ~40 min even if you listen the whole thing). Carver Mead's long lecture is a deepdive into understanding from physics - completely optional & it is pretty obvious from YT page description. You acknowledged the other one was really short & something you appreciate. Milman & Halkias suggestion was for Chapter 1 (~15 pages) only. The "grandpa introduction to someone who starts at 0" seems also been quoted out of context for Wikipedia.

Misquoting someone isn't nice & probably not in good faith. I can't say for everyone, but a sizeable crowd here would consider that wasting other person's time rather than seek answers.

Re:How do transistors work, anyway? by itishappy on Tuesday November 29, 2022 @05:59PM (#33794578)
For the record, this is my first time asking this question and it's the first time these links have been posted to this thread. I had no intention of misquoting you, nor do I believe I have done so. I'll be honest, I missed your mention of Millman & Halkias as I've scanned the thread. Why assume ill intent?

I love these! Thanks! However, I still take the same issue with them...

The first link still seeks to answer very different questions than the article. Note how there's still no mention of doping, depletion region, or really anything about how transistors actually work. It seems like it's more interested in answering "how would I use transistors?" instead of "how do transistors work?"

The second article is a lot closer in scope, but still skips the whole how and why semiconductors issue. It also feels like it relies on the user already having a practical background (and sure enough, it's module 3.3 of a full course).

To illustrate my point, I find the first three sections of the article to be the most interesting: The physics of conduction, The case of semiconductors, and Semiconductor junctions. I've yet to see similar treatment of these topics in any of the other links presented.

(Note: Millman & Halkias actually do seem to cover exactly this!)

> Also are you worried about the information or the presentation? You need non-handwavy info in textual format strictly.

Frankly, no. That's what courses and reference texts are for, and if you're working with electronics you can easily find one.

Since this was posted on HN, I view this article from the lens of a software engineer who's curious what goes on inside their processor. The type of person who has no intention of soldering anything together, but who would love an explanation for what makes their computer tick. Your short video did a fine job of this, but I personally find Ben Eater's the best YouTube content (hence why I mentioned only it), but I still maintain this is the perfect piece for curious hackers who prefer to read.

Re:How do transistors work, anyway? by matkoniecz on Tuesday November 29, 2022 @12:36PM (#33790603)
Can you recommend a better article?
Re:How do transistors work, anyway? by Koshkin on Tuesday November 29, 2022 @02:00PM (#33791654)
Re:How do transistors work, anyway? by amirhirsch on Tuesday November 29, 2022 @01:22PM (#33791174)
You might be interested in this substantially more in depth collection of article about semiconductor physics: http://britneyspears.ac/lasers.htm
Re:How do transistors work, anyway? by anikom15 on Tuesday November 29, 2022 @02:52PM (#33792350)
https://youtu.be/KqIOGGjPFQU

I find this to be the best concise explanation of the PN junction, which is enough to figure out how a transistor works on one’s own.

Re:How do transistors work, anyway? by oumua_don17 on Wednesday November 30, 2022 @06:01AM (#33799166)
Agreed. One of the best books to understand how transistors work is the GE transistor manual from 1964 :). [1] PS: pdf link

[1] https://worldradiohistory.com/BOOKSHELF-ARH/GE-Books/GE-Tran...