i worked as an engineering tech for Analog in 1970 when they were still in Cambridge on Binney St. I worked under Lew Counts on opamps and mulltiplier modules. I learned a lot in that year and put it to use for the rest of my career in electronics, I've been retired for 15 years now - keep up the good work.
Wow! I met Lew once, briefly, at the Analog Afficionados get together. (I was negative three years old in 1970.) I am having a blast helping the next generation of engineers, I work with a few that are really digging into old-school analog - there is hope!
Not attending, but somehow this popped into my feed. Really cool bits of history you’ve brought forward! Also this is the first I’ve heard of the see-saw analogy. Definitely keeping that in my back pocket for future tutoring.
From a customer, great company and amazing customer support. Very nice video. One of my favourite books is my hard copy of the AD OPAMP applications and its seminar companion.
Oh crap, now I feel old. I used an analog computer in grad school in the 1960s to calculate chemical kinetic parameters. Great talk, thanks for sharing.
I knew, or more accurately knew of, most of your material, but I find great value in your presentation because of the simple way you explain things. I just subscribed so i will be around for the rest of the show! Nice work!
Building intuition is the reason I'm watching these videos. I have no background in electronics other than curiosity and a few classes on the fundamentals. Opamps are awesome and I just never had a good feel for how they operate. Now I feel like I could actually make something with them!
Ermahgerd, it's Gersberms! Do it! The board used in the workshop this is for is described here: www.digikey.com/en/blog/an-op-amp-experimenter-board, design files and LTspice simulations are here: github.com/analogdevicesinc/education_tools/tree/master/experiment-boards/op_amp_experimenter.
Love the video- glad it came up in my feed. Loved the part about your brother.. another modular synth nut here. Although I've gone beyond that now- eurorack synths were the gateway drug that got me into analog circuit design.
I'm convinced I would have had a decade or more head start on really understanding electronics IF: * Every 555 circuit had the internal block diagram drawn, and every pin name written out. Yeah, Forrest Mimms books are great, but drawing a 555 as a rectangle with numbered pins only, does nothing for understanding. Worse, it makes it seem mysterious and intractable. * I had skipped learning the stupid inverting gain (-Rf/Rin) and noninverting gain (1+Rf/Rin) formulas for basic op-amp circuits, and had simply been told "dude, the output does whatever it has to to keep the inputs at the same voltage, you figure it out." One of my favorite interview questions is a transimpedance amplifier, with a current source temperature sensor. I watch to see if the candidate gets wrapped around the axle and can't recover after realizing they can't use a canned formula. Then I'll give the hint about keeping the inputs at the same voltage - if they recover on the spot, great! No penalty. I forget when I first started using the seesaw analogy, whether it materialized in my brain organically, or if I'd seen it somewhere. Either way, it's a great analogy!
Aah, what memories! When I was still a student, I was part time working, under a fabulous, incredibly multi-talented engineer. We needed for the company production lines servo controls. Did not want the commercial drifty tube amplifiers. So my boss designed an op-amp at first with 3 matched pairs of 2N930. I built and tested it, but found it had too much oscillation tendencies (too much gain). With that knowledge te boss reduced the differential stages to 2, with slightly optimized operating currents. We built some tens f these op-amps, until reasonably priced commercial modules became available. Then it was trying the first IC op-amps from Fairchild. ‘706 - no good, could not handle -15 V power. Then ’709 - good, if we added the latch up protection diodes. Finally ‘741 - good, although slower than the ‘709. . Later, my that time boss needed a multi-stage analog computer for some thermal process simulations. I volunteered to design and build it. I think it was 8-amp plus a couple of special functions layout with a bunch of banana sockets and plug-in components with 1% resistors as well as selected capacitor modules. Unlike the commercial +/- 100V tube based analog computer at the university lab I had used, my design was just +/- 15 V, but with ‘740 & ‘725 IC combos, it was working quite adequately. . At even later time, in a different division of the same corporation, I designed a very fast temperature sensor around one of the mentioned platinum resistors. That was used in troubleshooting of some 800 m/minute moving hot cylinder surface. That instrument was always available on a moments notice, unlike the alternative, a liquid nitrogen cooled thermal video camera, which we rented a couple of times. So, I have been there, seen those…
I consider myself a "mix-signal" engineer - I have to process all the analog signals in the best way possible to get good digital signals out them. So picking the right op-amp can be critical for some applications. My most recent ones have involved a raw sensor that put out currents in the nanoamp range, and getting some very clean (i.e. low-noise) audio and ultrasonic signals. You know you're "done" when you can see the noise floor of the ADC and the microphone. One other thing the simulations are good for are verifying your circuit equations. For non-trivial op-amp applications, (i.e. more than just a simple gain) you can verify your circuit equations with SPICE to make sure they're correct before handing them over to the software person for translating an ADC output into a reading from the sensor.
Yes! For DC applications, AN96 ( www.analog.com/media/en/technical-documentation/app-notes/an96fa.pdf ), Figure 5 shows the process of "optimizing" amplifier gain for the best overall dynamic range - basically, start out with your amplifier in unity gain. If the ADC output noise jumps, your amplifier is too noisy, why bother using it at all? If not, you're seeing the ADC noise floor. Then - start bumping the amplifier gain until the ADC output noise starts to rise - when it rises 3 dB, the amplifier and ADC noise contributions are equal. This fun paper ( conference.scipy.org.s3-website-us-east-1.amazonaws.com/proceedings/scipy2021/adi_sdg.html ) goes into a bit more detail, and adds LTspice and digital filter models to the mix. Some newer devices are enabling some hands-on mixed-mode signal chain labs on AC signals, more applicable to audio / ultrasonic. Stay tuned!
On July 8 1947, RAAF public information officer Walter Haut issued a press release stating that the military had recovered a "flying disc" near Roswell. The first transistor was successfully demonstrated on December 23, 1947, at Bell Laboratories in Murray Hill, New Jersey. Jus' Sayin'
You spoke of early HP instruments. There was a vacuum tube (high impedance input) voltmeter designed by David Packard which incorporated very strong negative feedback in its circuitry. It was considered quite an advance at the time.
Never had an HP, but there was an old Heathkit VTVM hanging around my lab when I was a kid. I didn't know how to take full advantage of it at the time. And the HP archive (and BAMA for that matter), are pretty amazing, I hope they never go away. Here's the manual for the 410B VTVM! hparchive.com/Manuals/HP-410B-Manual-SNprefix-024.pdf
You mentioned negative feedback being used to reduce distortion but another key benefit of operational amplifiers is they have a differential pair input stage which greatly reduces second harmonic distortion. Picture the asymmetry in your spice simulator for a single transistor amplifier. If this signal is inverted and then subtracted to form the common output the result will be significantly more symmetrical for positive and negative signals. When feedback is applied this linearity is improved further.
Ah! But this is actually not an upside. Just a difference. They reduce even harmonics but increase odd harmonics. Conservation of energy. There are many applications in instrumentation where the intrinsic noise generated by having a differential pair input stage outweighs the possible benefits of rejecting extrinsic noise, so we use single ended amplifiers.
Best part of my day job is mentoring new college grads, it's a great way to avoid grumpiness! Now if only there was an antidote to becoming one of the "old guys"...
A reminder for the kids playing with microcontrollers that nothing in the Universe is digital. It's all smooth and wiggley. Time, light, gravity? Smooth strait lines in all directions. P.S. I must build that Lorenz Attractor circuit!
The board files for that collection of chaos circuits are up on his GitHub! I ordered a bunch, just need the motivation to order parts and assemble them. Oh and one of the funnest parts of my job is teaching kids (new college grads) analog, and even better, mixed signal electronics. Ugh... "kids", I hope I'm not getting old yet...
In the anemometer circuit don't you have to use an identical platinum element in the opposite arm ? Else how will you differentiate cooling due to ambient temperature and wind.
Absolutely, at least if you want it to automatically compensate - the snippet from "Figure 3: CTA bridge circuit" shows a potentiometer in the adjacent arm. I've seen various configurations, but yeah, you got the right idea.
I am 100% stealing the see-saw analogy when I start my video series on op-amp basics. (Still working on basic transistors, with occasional videos wandering off elsewhere.)
Please do! I stole it myself, after all :) I think I put some links in the link dump slide. Also if you're doing op-amp basics, take a peek at this "experimenter board", which is released under Creative Commons BY-SA, link to the design files in the description: ruclips.net/video/zzXmWyu_rVM/видео.html . The SIP pattern down the centre is designed to take this little discrete op-amp board: github.com/analogdevicesinc/education_tools/tree/master/experiment-boards/transistor-op-amp . The discrete op-amp boards are so cheap, you could build up transistor subcircuits (current mirror, diff pair, gain stage, output stage, etc.) on individual boards, analyze them, then run the complete op-amp as a finale. We've got various subsets of this in ADI's Active Learning exercises.
Have you ever thought of using memristors instead of regular resistors with op amps? if its possible to control when the memristor changes its resistance It can greatly increase the use cases of op amps, but it requires a lot of r&d to develop such a memristor
When they're in stock at DigiKey, I'll snag a few :) Until then, a web search on "memristor LTspice" turns up a few hits, might have to play around with some of those in simulation....
I have a colleague that built a DTMF generator using the Three Fives discrete 555 ( shop.evilmadscientist.com/productsmenu/652 ) and XL741 discrete op-amp ( shop.evilmadscientist.com/productsmenu/762 ). Except - he used the 555 as the amplifier, and the 741 as the oscillator, and he said that "each did the other's job better than it could do its own job". The point being, you find a weird enough engineer, lots of things are possible! For sure you could make an AM transmitter out of a 555 - superhet receiver might take a bit more thought, since you'd need to implement multiplication function...
"no one uses analog anymore" then the camera cuts right to the world of Electric Guitar Effect Pedals where everyone swears analog circuits sounds better than digital
Physical digital effects barely exist anyway. Real-Time effects are usually Analogue (exept some things like delay that can be done better digitally), while Digital Effects are usually used as software in post-production or at most by a Computer in a Stage-Rack, but almost never a Pedal.
Very informative! and it makes me want to ask what your response would be to so called audiophile or audio enthusiasts that believe that the sound from a discrete op amp circuit is better somehow than a high-quality integrated circuit op amp. I don't know if you've heard of one such discrete op-amp, marketed under the name Sparkos. I'm sure if you type that into a search on RUclips, you'll undoubtedly find some reviewers that just love this drop-in replacement to an 8-pin dual op-amp.
I've definitely seen these around. If you poke around in the old Linear Tech appnotes, you'll see quite a few circuits that augment an op-amp with a discrete input stage for one purpose or another - noise, bias current, input capacitance, etc. Here's a photodiode transimpedance amplifier that illustrates the idea: www.analog.com/en/resources/technical-articles/1mw-transimpedance-amplifier-achieves-near-theoretical-noise-performance.html (In an abundance of caution, the next statement is distilled sarcasm. See Poe's Law: en.wikipedia.org/wiki/Poe%27s_law ) One thing's for sure on the audio applications - make sure your speaker wire costs at least $1000 per meter, or else you're clearly corrupting your ears 🤣
I haven't watched the whole video, but it would have been a nice touch to explain at the outset where the term "OP AMP" stems from. I have seen other videos about op amps and one said they were so named because they can do mathematical operations. This is just his fantasy. They were called op amps because they were "operational", as opposed to "aspirational". This is demonstrated in your video around the three minute mark where you show the ideal attributes of op amps. Nothing to do with maths at all, although they can be configured to do this job very effectively. I like the video and its format, but we mustn't let false information gain a foothold. I am old now and after I have "moved on", I worry that the false info will propagate and become fact. Greetings from an old Australian retired technician.
I don't have enough personal experience with the history, coming into the industry "relatively late" in 2001. I'll defer the Philbrick Archive on this one. www.philbrickarchive.org It's easy to get lost in that site, just tons of history, old application notes, and of course, "Philbrick Analog Computing Equipment for Modeling Measuring Manipulating and Much Else" (Philbrick Researches, Inc.... Is Often Inclined to Boast 🤣)
Hey kiddies, the world is analog. You have to amplify and treat (filter, compress, expand, etc) the signal before you can convert it to digital. Yup, that's right, kids.
_"Nobody uses analogue anymore."_ Ha! That's probably one of the most insidious thoughts out there, because _everybody_ uses analogue, whether they want to or not. I've seen plenty of digital systems that didn't work because the designer didn't realise it's not actually "digital" until he gets all the analogue aspects of design correct.
Strays components with resistance, capacitance and inductance will naturally form everywhere throughout the digital designs. The interferences and propagation delays caused by these RLC is nothing but analog.
I almost always end up going with other suppliers than Analog Devices due to cost vs performance ratio and it's kind of funny to see so much bragging about how much they are charging for these devices that came out in the 80s lol. Otherwise interesting video.
I'm a rebellious person. Whenever I can, I prefer to do things with FPGA, and over the years I have tried pretty much every sigma-delta trick that's been there in the public. Still, when it comes to really high speed (10Mhz+), really low power, or really extreme temperatures, I still resort to OpAmps.
Of course it's getting views. I just paused the video to get pumpkin pie & ice cream then carried on. I particularly like the fact that Spice throws in random tolerances to keep you honest. No mention of the OG 709 & 741 in the tin can package? Wassup with that?
I know, I know... I had half an hour to talk about a subject some have spent their lifetimes on, something had to get cut 😭 I have a small collection of canned op-amps that I would have dragged out given more time and energy... maybe for a future part deux.
I like the definition of an op amp as a "voltage divider with gain".
i worked as an engineering tech for Analog in 1970 when they were still in Cambridge on Binney St. I worked under Lew Counts on opamps and mulltiplier modules. I learned a lot in that year and put it to use for the rest of my career in electronics,
I've been retired for 15 years now - keep up the good work.
Wow! I met Lew once, briefly, at the Analog Afficionados get together. (I was negative three years old in 1970.)
I am having a blast helping the next generation of engineers, I work with a few that are really digging into old-school analog - there is hope!
Not attending, but somehow this popped into my feed.
Really cool bits of history you’ve brought forward! Also this is the first I’ve heard of the see-saw analogy. Definitely keeping that in my back pocket for future tutoring.
From a customer, great company and amazing customer support. Very nice video. One of my favourite books is my hard copy of the AD OPAMP applications and its seminar companion.
Oh crap, now I feel old. I used an analog computer in grad school in the 1960s to calculate chemical kinetic parameters. Great talk, thanks for sharing.
My college seminar paper presentation in 1975 was on OpAmps. Beautiful explanation and analogy.🎉
I knew, or more accurately knew of, most of your material, but I find great value in your presentation because of the simple way you explain things. I just subscribed so i will be around for the rest of the show! Nice work!
Excellent video, always had a soft spot of op-amps and their versatility.
Building intuition is the reason I'm watching these videos. I have no background in electronics other than curiosity and a few classes on the fundamentals. Opamps are awesome and I just never had a good feel for how they operate. Now I feel like I could actually make something with them!
Ermahgerd, it's Gersberms! Do it! The board used in the workshop this is for is described here: www.digikey.com/en/blog/an-op-amp-experimenter-board, design files and LTspice simulations are here: github.com/analogdevicesinc/education_tools/tree/master/experiment-boards/op_amp_experimenter.
Love the video- glad it came up in my feed. Loved the part about your brother.. another modular synth nut here. Although I've gone beyond that now- eurorack synths were the gateway drug that got me into analog circuit design.
Said brother shows up here and there, here he is building a tremolo pedal: ruclips.net/video/9aJ5hn9mQ5o/видео.html
Perfect analogy with the seesaw. Stuck in my only learn by depictions brain forever. Many thanks.
I'm convinced I would have had a decade or more head start on really understanding electronics IF:
* Every 555 circuit had the internal block diagram drawn, and every pin name written out. Yeah, Forrest Mimms books are great, but drawing a 555 as a rectangle with numbered pins only, does nothing for understanding. Worse, it makes it seem mysterious and intractable.
* I had skipped learning the stupid inverting gain (-Rf/Rin) and noninverting gain (1+Rf/Rin) formulas for basic op-amp circuits, and had simply been told "dude, the output does whatever it has to to keep the inputs at the same voltage, you figure it out."
One of my favorite interview questions is a transimpedance amplifier, with a current source temperature sensor. I watch to see if the candidate gets wrapped around the axle and can't recover after realizing they can't use a canned formula. Then I'll give the hint about keeping the inputs at the same voltage - if they recover on the spot, great! No penalty.
I forget when I first started using the seesaw analogy, whether it materialized in my brain organically, or if I'd seen it somewhere. Either way, it's a great analogy!
@@thorenscientificThe seesaw analogy is absolutely brilliant! And I'm totally with you on the 555 schematics and op-amp formulas.
Hi sir. This is more than a coincidence. I am using AD620 in one of my projects. Great to meet you.
Fantastic explanation and great links between history and modern tools and opamps
Aah, what memories! When I was still a student, I was part time working, under a fabulous, incredibly multi-talented engineer. We needed for the company production lines servo controls. Did not want the commercial drifty tube amplifiers. So my boss designed an op-amp at first with 3 matched pairs of 2N930. I built and tested it, but found it had too much oscillation tendencies (too much gain). With that knowledge te boss reduced the differential stages to 2, with slightly optimized operating currents. We built some tens f these op-amps, until reasonably priced commercial modules became available. Then it was trying the first IC op-amps from Fairchild. ‘706 - no good, could not handle -15 V power. Then ’709 - good, if we added the latch up protection diodes. Finally ‘741 - good, although slower than the ‘709.
.
Later, my that time boss needed a multi-stage analog computer for some thermal process simulations. I volunteered to design and build it. I think it was 8-amp plus a couple of special functions layout with a bunch of banana sockets and plug-in components with 1% resistors as well as selected capacitor modules. Unlike the commercial +/- 100V tube based analog computer at the university lab I had used, my design was just +/- 15 V, but with ‘740 & ‘725 IC combos, it was working quite adequately.
.
At even later time, in a different division of the same corporation, I designed a very fast temperature sensor around one of the mentioned platinum resistors. That was used in troubleshooting of some 800 m/minute moving hot cylinder surface. That instrument was always available on a moments notice, unlike the alternative, a liquid nitrogen cooled thermal video camera, which we rented a couple of times. So, I have been there, seen those…
Great stories!
I consider myself a "mix-signal" engineer - I have to process all the analog signals in the best way possible to get good digital signals out them. So picking the right op-amp can be critical for some applications. My most recent ones have involved a raw sensor that put out currents in the nanoamp range, and getting some very clean (i.e. low-noise) audio and ultrasonic signals. You know you're "done" when you can see the noise floor of the ADC and the microphone.
One other thing the simulations are good for are verifying your circuit equations. For non-trivial op-amp applications, (i.e. more than just a simple gain) you can verify your circuit equations with SPICE to make sure they're correct before handing them over to the software person for translating an ADC output into a reading from the sensor.
Yes! For DC applications, AN96 ( www.analog.com/media/en/technical-documentation/app-notes/an96fa.pdf ), Figure 5 shows the process of "optimizing" amplifier gain for the best overall dynamic range - basically, start out with your amplifier in unity gain. If the ADC output noise jumps, your amplifier is too noisy, why bother using it at all? If not, you're seeing the ADC noise floor. Then - start bumping the amplifier gain until the ADC output noise starts to rise - when it rises 3 dB, the amplifier and ADC noise contributions are equal. This fun paper ( conference.scipy.org.s3-website-us-east-1.amazonaws.com/proceedings/scipy2021/adi_sdg.html ) goes into a bit more detail, and adds LTspice and digital filter models to the mix. Some newer devices are enabling some hands-on mixed-mode signal chain labs on AC signals, more applicable to audio / ultrasonic. Stay tuned!
On July 8 1947, RAAF public information officer Walter Haut issued a press release stating that the military had recovered a "flying disc" near Roswell.
The first transistor was successfully demonstrated on December 23, 1947, at Bell Laboratories in Murray Hill, New Jersey.
Jus' Sayin'
There was a blinding lightning, and in a sec he farted.
Just saying
Every human being ever has consumed water at some point in their life.
Every human being ever at some point dies.
Jus' Sayin'
Just to say that a 'flying disc' carries a striking resemblance with the model of flat earth. It can't be a coincidence.
You spoke of early HP instruments. There was a vacuum tube (high impedance input) voltmeter designed by David Packard which incorporated very strong negative feedback in its circuitry. It was considered quite an advance at the time.
Never had an HP, but there was an old Heathkit VTVM hanging around my lab when I was a kid. I didn't know how to take full advantage of it at the time.
And the HP archive (and BAMA for that matter), are pretty amazing, I hope they never go away. Here's the manual for the 410B VTVM! hparchive.com/Manuals/HP-410B-Manual-SNprefix-024.pdf
Great lecture!
You mentioned negative feedback being used to reduce distortion but another key benefit of operational amplifiers is they have a differential pair input stage which greatly reduces second harmonic distortion. Picture the asymmetry in your spice simulator for a single transistor amplifier. If this signal is inverted and then subtracted to form the common output the result will be significantly more symmetrical for positive and negative signals. When feedback is applied this linearity is improved further.
Ah! But this is actually not an upside. Just a difference. They reduce even harmonics but increase odd harmonics. Conservation of energy. There are many applications in instrumentation where the intrinsic noise generated by having a differential pair input stage outweighs the possible benefits of rejecting extrinsic noise, so we use single ended amplifiers.
Great talk!
Thanks so much for this. Great explanations mixed with humour. Watch out for those grumpy old guys.
Regards, Kieron.
Best part of my day job is mentoring new college grads, it's a great way to avoid grumpiness! Now if only there was an antidote to becoming one of the "old guys"...
A reminder for the kids playing with microcontrollers that nothing in the Universe is digital. It's all smooth and wiggley.
Time, light, gravity? Smooth strait lines in all directions.
P.S. I must build that Lorenz Attractor circuit!
The board files for that collection of chaos circuits are up on his GitHub! I ordered a bunch, just need the motivation to order parts and assemble them. Oh and one of the funnest parts of my job is teaching kids (new college grads) analog, and even better, mixed signal electronics. Ugh... "kids", I hope I'm not getting old yet...
Interesting little video, thanks for posting.
Nice class. Thank you.
That makes Keysight the only REAL HP!
IMHO, that would be accurate :)
@@thorenscientific :)
In the anemometer circuit don't you have to use an identical platinum element in the opposite arm ? Else how will you differentiate cooling due to ambient temperature and wind.
Absolutely, at least if you want it to automatically compensate - the snippet from "Figure 3: CTA bridge circuit" shows a potentiometer in the adjacent arm. I've seen various configurations, but yeah, you got the right idea.
I am 100% stealing the see-saw analogy when I start my video series on op-amp basics. (Still working on basic transistors, with occasional videos wandering off elsewhere.)
Please do! I stole it myself, after all :) I think I put some links in the link dump slide. Also if you're doing op-amp basics, take a peek at this "experimenter board", which is released under Creative Commons BY-SA, link to the design files in the description: ruclips.net/video/zzXmWyu_rVM/видео.html . The SIP pattern down the centre is designed to take this little discrete op-amp board: github.com/analogdevicesinc/education_tools/tree/master/experiment-boards/transistor-op-amp . The discrete op-amp boards are so cheap, you could build up transistor subcircuits (current mirror, diff pair, gain stage, output stage, etc.) on individual boards, analyze them, then run the complete op-amp as a finale. We've got various subsets of this in ADI's Active Learning exercises.
Have you ever thought of using memristors instead of regular resistors with op amps? if its possible to control when the memristor changes its resistance It can greatly increase the use cases of op amps, but it requires a lot of r&d to develop such a memristor
When they're in stock at DigiKey, I'll snag a few :) Until then, a web search on "memristor LTspice" turns up a few hits, might have to play around with some of those in simulation....
Is it possible to make something like a superhet receiver with a 555?
I have a colleague that built a DTMF generator using the Three Fives discrete 555 ( shop.evilmadscientist.com/productsmenu/652 ) and XL741 discrete op-amp ( shop.evilmadscientist.com/productsmenu/762 ). Except - he used the 555 as the amplifier, and the 741 as the oscillator, and he said that "each did the other's job better than it could do its own job". The point being, you find a weird enough engineer, lots of things are possible! For sure you could make an AM transmitter out of a 555 - superhet receiver might take a bit more thought, since you'd need to implement multiplication function...
Why don't you learn what a 555 is before you go asking dumb questions.
Super cool vid…
"no one uses analog anymore"
then the camera cuts right to the world of Electric Guitar Effect Pedals
where everyone swears analog circuits sounds better than digital
It’s more than sound, there’s a “feel” aspect to it, emotions are real, shocking, isn’t it.
Physical digital effects barely exist anyway. Real-Time effects are usually Analogue (exept some things like delay that can be done better digitally), while Digital Effects are usually used as software in post-production or at most by a Computer in a Stage-Rack, but almost never a Pedal.
The mouse SIZE control is your friend.
Very informative! and it makes me want to ask what your response would be to so called audiophile or audio enthusiasts that believe that the sound from a discrete op amp circuit is better somehow than a high-quality integrated circuit op amp. I don't know if you've heard of one such discrete op-amp, marketed under the name Sparkos. I'm sure if you type that into a search on RUclips, you'll undoubtedly find some reviewers that just love this drop-in replacement to an 8-pin dual op-amp.
I've definitely seen these around. If you poke around in the old Linear Tech appnotes, you'll see quite a few circuits that augment an op-amp with a discrete input stage for one purpose or another - noise, bias current, input capacitance, etc. Here's a photodiode transimpedance amplifier that illustrates the idea: www.analog.com/en/resources/technical-articles/1mw-transimpedance-amplifier-achieves-near-theoretical-noise-performance.html
(In an abundance of caution, the next statement is distilled sarcasm. See Poe's Law: en.wikipedia.org/wiki/Poe%27s_law )
One thing's for sure on the audio applications - make sure your speaker wire costs at least $1000 per meter, or else you're clearly corrupting your ears 🤣
I haven't watched the whole video, but it would have been a nice touch to explain at the outset where the term "OP AMP" stems from. I have seen other videos about op amps and one said they were so named because they can do mathematical operations. This is just his fantasy. They were called op amps because they were "operational", as opposed to "aspirational". This is demonstrated in your video around the three minute mark where you show the ideal attributes of op amps. Nothing to do with maths at all, although they can be configured to do this job very effectively. I like the video and its format, but we mustn't let false information gain a foothold. I am old now and after I have "moved on", I worry that the false info will propagate and become fact. Greetings from an old Australian retired technician.
I don't have enough personal experience with the history, coming into the industry "relatively late" in 2001. I'll defer the Philbrick Archive on this one. www.philbrickarchive.org
It's easy to get lost in that site, just tons of history, old application notes, and of course, "Philbrick Analog Computing Equipment for Modeling Measuring Manipulating and Much Else" (Philbrick Researches, Inc.... Is Often Inclined to Boast 🤣)
Very informative very demure
Hey kiddies, the world is analog. You have to amplify and treat (filter, compress, expand, etc) the signal before you can convert it to digital. Yup, that's right, kids.
and offset and span !!!
_"Nobody uses analogue anymore."_ Ha!
That's probably one of the most insidious thoughts out there, because _everybody_ uses analogue, whether they want to or not. I've seen plenty of digital systems that didn't work because the designer didn't realise it's not actually "digital" until he gets all the analogue aspects of design correct.
Strays components with resistance, capacitance and inductance will naturally form everywhere throughout the digital designs. The interferences and propagation delays caused by these RLC is nothing but analog.
I almost always end up going with other suppliers than Analog Devices due to cost vs performance ratio and it's kind of funny to see so much bragging about how much they are charging for these devices that came out in the 80s lol. Otherwise interesting video.
I'm a rebellious person. Whenever I can, I prefer to do things with FPGA, and over the years I have tried pretty much every sigma-delta trick that's been there in the public. Still, when it comes to really high speed (10Mhz+), really low power, or really extreme temperatures, I still resort to OpAmps.
Analog Devices making Microprocessors is as confusing as like Valvo making any Semiconductor.
Muy interesante
Triode is more like a JFET.
Noted! My vacuum tube experience is quite limited - gotta build up a few amplifier kits to start building some intuition.
I've heard hams jokingly call them GlassFETs.
Of course it's getting views. I just paused the video to get pumpkin pie & ice cream then carried on. I particularly like the fact that Spice throws in random tolerances to keep you honest. No mention of the OG 709 & 741 in the tin can package? Wassup with that?
I know, I know... I had half an hour to talk about a subject some have spent their lifetimes on, something had to get cut 😭 I have a small collection of canned op-amps that I would have dragged out given more time and energy... maybe for a future part deux.
AD..🥐Rock & Roll🌯
🥬Op-Amps🥗