"Legendary" is an under-statement. Widlar's colorful personality is an interesting read, "every idiot can count to one". Thanks Professor Lanterman, for keeping Widlar's creations alive.
Whoa! I have the Bob Widlar photo with the cigarette and middle finger and "digital? every idiot can count to one" quote hanging up in my cube at work, right next to a photo of Don Buchla posing with a 400. They were both born in 1937. It's a little shrine, to inspire me to stay creative designing digital logic.
@5:19: Actually, you can solve for I_o in closed form with the Lambert W function: I_o = (V_T * W[(I_ref * R_e)/V_T]) / R_e. Lambert's W solves a lot of these exponential equations in closed form and is implemented in Mathematica as ProductLog[ ], and in MatLab, too; forget the function name. Nice video, though, clear explanations and good exposition.
Hi Aaron, I watched the short video clip you mention where Rick Beato talks about education and UA-cam. And of course he is right about the fact that we all had to switch instantly from being IRL to getting glued to your chair while trying, without any preparation, to keep students going. It's like comparing apples to oranges, they are completely different. And the learning curve wasn't only in education. Just take a look at Seth Meyers, he was horrible in the early days, and he got better as time progressed. But getting back at education vs UA-cam. Education is about content, while most of UA-cam is about (at best) infotainment. It's about learning about something vs hearing about it. In Dutch we have a saying: "de klok horen luiden, maar niet weten waar de klepel hangt", which translates to something like "Have only superficial knowledge of". I am impressed with your videos, their content, and their quality.
Thanks, Prof. Aaron👍 Constructive criticism: It would have been helpful/nice to put the link in the information below your video rather than say, “Go search, buddy!” Nevertheless, I did find that portion of the video and watched 😉 Back in the days of chalk boards and analog oscilloscopes, studying electrical engineering and math, I found it helpful to find a good book on the subject, a book that I could learn from. Not all college textbooks are the same. Once I found a book that worked for me, I could study and restudy until I learned the material. I could not do that in a lecture. These days, cameras are cheap, and I would have loved to have had a camera in those days, so I could go back and rewatch a portion of the lecture that I needed to in order to relearn what I needed to learn. Trying to learn something from a video, that is exactly what I do, whether it’s a lecture on UA-cam or downloaded from MIT. I love the ability to go back and watch until it makes sense or to pause and seek help to learn the material before moving on to later material in a subject. Anyway, what works best for me is a video lecture, a good book, and some way to experiment with the material. Being able to experiment with the material is key for me and where I make mistakes to learn from, which is why I HATE graded homework. I do like corrected homework, but homework should never count towards a final grade in a course. When I was studying electrical engineering, the electrical engineering lab closed at 8:00 PM, which is way too early for harried electrical engineering students. No computer lab closed that early, if ever. That’s probably why I never practiced as an electrical engineer and took programming jobs instead. Imagine if professors could spend time answering students’ questions rather than lecturing. With the tools available today, students could watch videos of the lectures, work problems, and get help from their professors during the time that would be otherwise spent on in-person lectures. Anyway, I hope that helps, and thanks again, Prof. Aaron. I have been getting back into HAM radio and have enjoyed your videos posted on UA-cam!!
Just a suggestion for your continuing education, have you tried working with chatGPT to discuss circuit design? I just asked it some specific Widlar current mirror questions and its quite knowledgeable. Even the free tier, works fine.
@@CraigHollabaugh Nope, ChatGPT is just a LLM, and it only generates nice texts. No insight there. And trust me, I've checked it thoroughly with some simple embedded coding challenges: syntax and semantics are perfect (of course, because it is a language model), but the code doesn't do what you want it to do.
0:30 Bob Pease on the left. Jim Williams on the right. Bob really liked his VW Beetle, as he wrote in his Pease Porridge column. Bob very sadly died in a minor car accident leaving a memorial service for Jim (had stroke). A very bad week... Refs: en.wikipedia.org/wiki/Bob_Pease en.wikipedia.org/wiki/Jim_Williams_(analog_designer)
VT stands for the "thermal voltage" -- VT = kT/Q, where k is Boltzmann's constant, T is the temperature in Kelvin, and Q is the charge of an electron. It's commonly taken to be 25 mV or 26 mV for hand calculations. The exponential comes from the Ebers-Moll model of BJT behavior. It is indeed magic! :)
Bro really gotta call me out like that 😅 Hard to complain when getting a topic you've personally requested, though (although I'm up the to challenge). At the very least I can offer partial thanks through feedback/thoughts as you've asked for. Firstly in relation to the video (maybe it might help with your own production for the future), and also generally on the topic you asked about at the end of the video. This one, 1:26, you pose what seems might be a central thesis this video is intended to answer: "making this minor change, has a very interesting effect." and then 'break into 12 minutes of equations' (if one wants to put the following in a negative light). As a serious higher education student, maybe I need teasing apart the video on my own for another hour and applying example concrete values to see what this interesting effect is, its applications and contrasts with previous circuits. Why did *I* think the extra resistor of Widlar's was so darn profound? Maybe to ask for more is asking too much, I'm unsure. I am however sure that I was left trying to parse out I had learnt at the end of the video, apart from the fact that in general this circuit seems to be a good candidate for generating very small currents without requiring large resistors. I feel like if you applied a single concrete example of values into the equations you are exploring (at the end of their derivation in a slide(s), generating a mA or uA current source and its rough output impedance, it would bring things together a lot better. For example at 10:27 I had an idea that I should theoretically now know the output impedance of the current source, a fairly important figure of merit for a current source, maybe how to calculate it, but was moderately confused instead. Had it grown larger with the addition of the resistor? What are all these generalisations? I find this general conclusion at the end of a lot of your videos, a lot of derivation (fine! The modern world can't exist without the math forever) but very few examples to tie its results together. Tying into your open question, maybe a good portion of the "value of these education institutions and courses" is getting the examples and workings and feedback where they are far more left by the wayside on the open internet/YT. I'll leave a comment on that in a second part.
In terms of education interacting with youtube, I don't think there's terribly much difference between online and IRL, for 'teachers who can't teach'. There are terrible ones who can't take a cohesive/engaging physical lecture to save themselves and also terrible ones who can't produce a coherent video lecture. The underlying problem is not a uniquely new one, and educators have been trying to solve different facets of it for the student for decades or even centuries now. On the engagement side of it, youtube has never primarily been about education; only when there is a corollary coincidence of motivations. A great deal of education topics are evergreen, yet youtube consistently wants us to interact with the latest hype topic from yesterday. Many a time I have wondered if there's some awesome little nuggets of videos that relate directly to my interests but that YT's search will never bother surfacing to me when it really wants me to just absorb the latest Veritasium instead. For instance there is a user "Simply Put" (@simplyput2796) who has made a treasure trove of practical electronics explainers, sort of a complement to a lot of your style of content, that I wonder how many people will continue to discover, now that they are no longer putting out a fresh video every week or month. If you'd like to see an absolute tour-de-force in YT education/engagement, Dr. Jorge S. Diaz (@jkzero) from 8 months ago has beeen putting out absolutely stunning videos on the historical pedagogy of quantum experiments leading to our current understanding on the topic. They don't try and "run from the math" either (like so many do when interacting with 'quantum physics' on YT), but they are absolutely mesmerisizing to watch. Just prior to your requested timestamp, Rick remarks that he personally gets a lot of his drive for putting out great videos from topics that he's passionate about, and by necessity, damn whether that content will be interesting for 2 million people or only 5 thousand. That resonates with me; there's a lot of jank I can get through as long as the person on the other side is clearly passionate about the topic and is clear enough to understand. YT educators shouldn't be so mindlessly scared of the ten-thousand dollar budgets of pro-YTers so long as they have a dedication to wanting to explain their subject; that will always give them a fighting chance. In terms of Traditional Education standing toe to toe with videos, I think most of the value of an institution comes from the organisational nature of the course, that one does not need discipline simply to find a cohesive outline of topics to approach in order to systematically learn a subject, the feedback loop and provided work that one gets hopefully as part and parcel of them taking a big loan to pay for it all. You can get a lot of the information piecemeal, sometimes in way higher quality on YT, but the huge investment of self-discipline required to deeply ingest in the same way is a price we all like to ignore. You don't ever have to convince yourself of having 'learnt' something if you don't have to take an end-of-semester test on it with a passing grade. Universities may have lost a pedastal of being a sole provider of access to high quality, high tier topics (although cough cough, that isn't always the case) but IMO that is not such a big loss to worry about, *if* they are still providing thorough courses that an invested student can easily succeed in. Although there *are* a great many that have taken the usefulness and quality of their courses for granted the last few decades, and yes now should be worried about students questioning their value.
Watched the Beato clip, it's true what he says. Just having a prof publish a chalkboard lecture isn't going to work well. What will distinguish (provide value) if the lecture is live streamed with full two-way video comm for paying students. Then later publishing the live stream for post consumption. The pre-recorded video/comment/reply isn't worth any tuition amount in this tiktok world.
Check out my lecture in this series, L20: BJT Differential Amplifiers with Ideal Tail currents and the two lectures that follow it. Also check out Lecture 26: BJT Current Mirrors at the 19:50 minute mark that talks about OTAs (current mirrors on top of diff amps), as well as L4.1: Voltage Controlled Amplifiers: Operational Transconductance Amps from my ECE4450 Analog Circuits for Music Synthesis class.
Improve your lecturing with one simple trick! How's that for a video title? But seriously, never use the word "what" unless you are asking a question and your delivery will be much improved. Eliminate all the "what this does is it" and "what you want to do is you" and "what you do now is" and "what you get is...". I did it when teaching and now it is a habit, and my UA-cam crusade. Nice video and I'm going to run thought it slower. Current mirrors often confuse me.
"Legendary" is an under-statement. Widlar's colorful personality is an interesting read, "every idiot can count to one". Thanks Professor Lanterman, for keeping Widlar's creations alive.
Thank you for your kind words!
Nice content, thanks for the videos. I worked in sales and marketing at Analog Devices for many years.
Whoa! I have the Bob Widlar photo with the cigarette and middle finger and "digital? every idiot can count to one" quote hanging up in my cube at work, right next to a photo of Don Buchla posing with a 400. They were both born in 1937. It's a little shrine, to inspire me to stay creative designing digital logic.
@5:19: Actually, you can solve for I_o in closed form with the Lambert W function: I_o = (V_T * W[(I_ref * R_e)/V_T]) / R_e. Lambert's W solves a lot of these exponential equations in closed form and is implemented in Mathematica as ProductLog[ ], and in MatLab, too; forget the function name. Nice video, though, clear explanations and good exposition.
Hi Aaron, I watched the short video clip you mention where Rick Beato talks about education and UA-cam. And of course he is right about the fact that we all had to switch instantly from being IRL to getting glued to your chair while trying, without any preparation, to keep students going. It's like comparing apples to oranges, they are completely different. And the learning curve wasn't only in education. Just take a look at Seth Meyers, he was horrible in the early days, and he got better as time progressed.
But getting back at education vs UA-cam. Education is about content, while most of UA-cam is about (at best) infotainment. It's about learning about something vs hearing about it. In Dutch we have a saying: "de klok horen luiden, maar niet weten waar de klepel hangt", which translates to something like "Have only superficial knowledge of".
I am impressed with your videos, their content, and their quality.
Electronics Engineering:
_Leading the world in Bob's-per-industry since 1939._
HAH!
5:14 - Mathematicians have invented the Lambert W function to solve these kinds of equations.
Thank you very much
You are very welcome! :)
Thanks, Prof. Aaron👍
Constructive criticism: It would have been helpful/nice to put the link in the information below your video rather than say, “Go search, buddy!” Nevertheless, I did find that portion of the video and watched 😉
Back in the days of chalk boards and analog oscilloscopes, studying electrical engineering and math, I found it helpful to find a good book on the subject, a book that I could learn from. Not all college textbooks are the same. Once I found a book that worked for me, I could study and restudy until I learned the material. I could not do that in a lecture. These days, cameras are cheap, and I would have loved to have had a camera in those days, so I could go back and rewatch a portion of the lecture that I needed to in order to relearn what I needed to learn. Trying to learn something from a video, that is exactly what I do, whether it’s a lecture on UA-cam or downloaded from MIT. I love the ability to go back and watch until it makes sense or to pause and seek help to learn the material before moving on to later material in a subject.
Anyway, what works best for me is a video lecture, a good book, and some way to experiment with the material. Being able to experiment with the material is key for me and where I make mistakes to learn from, which is why I HATE graded homework. I do like corrected homework, but homework should never count towards a final grade in a course. When I was studying electrical engineering, the electrical engineering lab closed at 8:00 PM, which is way too early for harried electrical engineering students. No computer lab closed that early, if ever. That’s probably why I never practiced as an electrical engineer and took programming jobs instead.
Imagine if professors could spend time answering students’ questions rather than lecturing. With the tools available today, students could watch videos of the lectures, work problems, and get help from their professors during the time that would be otherwise spent on in-person lectures.
Anyway, I hope that helps, and thanks again, Prof. Aaron. I have been getting back into HAM radio and have enjoyed your videos posted on UA-cam!!
Just a suggestion for your continuing education, have you tried working with chatGPT to discuss circuit design? I just asked it some specific Widlar current mirror questions and its quite knowledgeable. Even the free tier, works fine.
@@CraigHollabaugh Nope, ChatGPT is just a LLM, and it only generates nice texts. No insight there. And trust me, I've checked it thoroughly with some simple embedded coding challenges: syntax and semantics are perfect (of course, because it is a language model), but the code doesn't do what you want it to do.
@jandobbelsteen8953 I just asked it widlar current source questions for my original reply, no code involved.
@@CraigHollabaugh okay, sorry for my too hasty reply 😅
@jandobbelsteen8953 no problem, I've done it too.
I like your TITle screen. 1 and 0 at the same instance_
Thanks!
0:30 Bob Pease on the left. Jim Williams on the right.
Bob really liked his VW Beetle, as he wrote in his Pease Porridge column.
Bob very sadly died in a minor car accident leaving a memorial service for Jim (had stroke). A very bad week...
Refs:
en.wikipedia.org/wiki/Bob_Pease
en.wikipedia.org/wiki/Jim_Williams_(analog_designer)
That's horrible, losing two such brilliant minds like that...
They were absolute giants, and true men of science. Thank you for another excellent presentation professor Lanterman - greatly appreciated!
हे गुढ गणित मला तितकसं कळले नसले तरी त्यात गम्य आहे! अत्यंत सुंदर. Vbe= 0.7 V, पण हे VT काय आहे नाही उमजले. शिवाय Exp योजना कश्यानिमित्त?
VT stands for the "thermal voltage" -- VT = kT/Q, where k is Boltzmann's constant, T is the temperature in Kelvin, and Q is the charge of an electron. It's commonly taken to be 25 mV or 26 mV for hand calculations.
The exponential comes from the Ebers-Moll model of BJT behavior.
It is indeed magic! :)
Wawit, is this basically an electrical venturi effect!?
Hey... That's my profile picture 😆
Bro really gotta call me out like that 😅 Hard to complain when getting a topic you've personally requested, though (although I'm up the to challenge). At the very least I can offer partial thanks through feedback/thoughts as you've asked for. Firstly in relation to the video (maybe it might help with your own production for the future), and also generally on the topic you asked about at the end of the video.
This one, 1:26, you pose what seems might be a central thesis this video is intended to answer: "making this minor change, has a very interesting effect." and then 'break into 12 minutes of equations' (if one wants to put the following in a negative light). As a serious higher education student, maybe I need teasing apart the video on my own for another hour and applying example concrete values to see what this interesting effect is, its applications and contrasts with previous circuits. Why did *I* think the extra resistor of Widlar's was so darn profound? Maybe to ask for more is asking too much, I'm unsure. I am however sure that I was left trying to parse out I had learnt at the end of the video, apart from the fact that in general this circuit seems to be a good candidate for generating very small currents without requiring large resistors. I feel like if you applied a single concrete example of values into the equations you are exploring (at the end of their derivation in a slide(s), generating a mA or uA current source and its rough output impedance, it would bring things together a lot better. For example at 10:27 I had an idea that I should theoretically now know the output impedance of the current source, a fairly important figure of merit for a current source, maybe how to calculate it, but was moderately confused instead. Had it grown larger with the addition of the resistor? What are all these generalisations? I find this general conclusion at the end of a lot of your videos, a lot of derivation (fine! The modern world can't exist without the math forever) but very few examples to tie its results together.
Tying into your open question, maybe a good portion of the "value of these education institutions and courses" is getting the examples and workings and feedback where they are far more left by the wayside on the open internet/YT. I'll leave a comment on that in a second part.
In terms of education interacting with youtube, I don't think there's terribly much difference between online and IRL, for 'teachers who can't teach'. There are terrible ones who can't take a cohesive/engaging physical lecture to save themselves and also terrible ones who can't produce a coherent video lecture. The underlying problem is not a uniquely new one, and educators have been trying to solve different facets of it for the student for decades or even centuries now.
On the engagement side of it, youtube has never primarily been about education; only when there is a corollary coincidence of motivations. A great deal of education topics are evergreen, yet youtube consistently wants us to interact with the latest hype topic from yesterday. Many a time I have wondered if there's some awesome little nuggets of videos that relate directly to my interests but that YT's search will never bother surfacing to me when it really wants me to just absorb the latest Veritasium instead. For instance there is a user "Simply Put" (@simplyput2796) who has made a treasure trove of practical electronics explainers, sort of a complement to a lot of your style of content, that I wonder how many people will continue to discover, now that they are no longer putting out a fresh video every week or month. If you'd like to see an absolute tour-de-force in YT education/engagement, Dr. Jorge S. Diaz (@jkzero) from 8 months ago has beeen putting out absolutely stunning videos on the historical pedagogy of quantum experiments leading to our current understanding on the topic. They don't try and "run from the math" either (like so many do when interacting with 'quantum physics' on YT), but they are absolutely mesmerisizing to watch.
Just prior to your requested timestamp, Rick remarks that he personally gets a lot of his drive for putting out great videos from topics that he's passionate about, and by necessity, damn whether that content will be interesting for 2 million people or only 5 thousand. That resonates with me; there's a lot of jank I can get through as long as the person on the other side is clearly passionate about the topic and is clear enough to understand. YT educators shouldn't be so mindlessly scared of the ten-thousand dollar budgets of pro-YTers so long as they have a dedication to wanting to explain their subject; that will always give them a fighting chance.
In terms of Traditional Education standing toe to toe with videos, I think most of the value of an institution comes from the organisational nature of the course, that one does not need discipline simply to find a cohesive outline of topics to approach in order to systematically learn a subject, the feedback loop and provided work that one gets hopefully as part and parcel of them taking a big loan to pay for it all. You can get a lot of the information piecemeal, sometimes in way higher quality on YT, but the huge investment of self-discipline required to deeply ingest in the same way is a price we all like to ignore. You don't ever have to convince yourself of having 'learnt' something if you don't have to take an end-of-semester test on it with a passing grade. Universities may have lost a pedastal of being a sole provider of access to high quality, high tier topics (although cough cough, that isn't always the case) but IMO that is not such a big loss to worry about, *if* they are still providing thorough courses that an invested student can easily succeed in. Although there *are* a great many that have taken the usefulness and quality of their courses for granted the last few decades, and yes now should be worried about students questioning their value.
Watched the Beato clip, it's true what he says. Just having a prof publish a chalkboard lecture isn't going to work well. What will distinguish (provide value) if the lecture is live streamed with full two-way video comm for paying students. Then later publishing the live stream for post consumption. The pre-recorded video/comment/reply isn't worth any tuition amount in this tiktok world.
what has happened to the Widlars and Fullagers of these days? Analog design is a specialist discipline that doesnt seem to be as prized as it was then
I demand the thumbnail be changed back to the rude gesture
Hah! I'm actually running an experiment. After some time I'm going to switch it back to the rude gesture and see if the view rate goes up. :)
Omg just a diff amp
A current mirror is not diff amp at all, but you often see current mirrors on top of diff amps to form operational transconductance amplifiers.
Check out my lecture in this series, L20: BJT Differential Amplifiers with Ideal Tail currents and the two lectures that follow it. Also check out Lecture 26: BJT Current Mirrors at the 19:50 minute mark that talks about OTAs (current mirrors on top of diff amps), as well as L4.1: Voltage Controlled Amplifiers: Operational Transconductance Amps from my ECE4450 Analog Circuits for Music Synthesis class.
Can I get a smoke((○))
Improve your lecturing with one simple trick! How's that for a video title? But seriously, never use the word "what" unless you are asking a question and your delivery will be much improved. Eliminate all the "what this does is it" and "what you want to do is you" and "what you do now is" and "what you get is...". I did it when teaching and now it is a habit, and my UA-cam crusade.
Nice video and I'm going to run thought it slower. Current mirrors often confuse me.
UA-cam don’t recommend channel