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a video about electronics industry

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PG1995

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Hi!

I was watching the video below and couldn't understand few words said by Jack Kilby 21:38 "you could make any kind of component that you needed with one exception *** you could certainly make...". What is that "one exception"? Inductor? What does he say just after the words "one exception"? I have used "***" in place of those missing words. I'm sorry if it's not the right place to ask this kind of question. Thank you!

 

JimB

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What does he say just after the words "one exception"?
I hear it as "out of silicon".

I did not watch all of the video, but he did not appear to say which component could not be made from silicon.

JimB
 

Nigel Goodwin

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I hear it as "out of silicon".

I did not watch all of the video, but he did not appear to say which component could not be made from silicon.
I've not watched any of it, but fairly obviously there are numerous components that are made from other than silicon, such as germanium and gallium arsenide.

Funnily enough I was talking to my (Dutch) son in-law last year, he's a technician at the same University my daughter is doing post-doc research (she's a chemist).

As part of her research my daughter had to be 'clean room certified', as she uses the clean room facilities in her research. For the certification she had to make a wafer of solar cells, she showed it me, I was well impressed.

And Mike (the son in-law) was talking to me about manufacturing IC's, specifically acceleration sensors - which he had been tasked to do for one of the departments.

I just thought it was wonderful to have the capabilities of making your own IC if you needed to :D
 

PG1995

Active Member
Thank you!

Actually when I was watching that video I thought that Jack Kilby was referring to the inductor. The following is what I said in my first post above.

"I was watching the video below and couldn't understand few words said by Jack Kilby 21:38 "you could make any kind of component that you needed with one exception *** you could certainly make...". What is that "one exception"? Inductor?"

I remember many years ago I asked a question that if ICs ever contain inductors because they appear to contain almost every other electrical component. I was told that "almost never" and it was suggested that there exists a circuit called gyrator which can function as a capacitor and simulate an inductor. I thought that I should add to this topic so someone might find it useful.

Please let me know if I have something wrong or perhaps you can add more to it. Thank you.

"Inductors are used inside integrated circuits made for RF communication (e.g. wireless communication chip(s) in your phone).

However, having on-chip or off-chip inductors is still a compromise due to following reasons:

1. As has been noted here, on-chip inductors take up more chip space compared to capacitors or resistors.
2. Quality factor (Q) of on-chip inductors tends to be lower compared to off-chip inductors
3. Having on-chip inductors helps create a compact well integrated system solution
4. Package parasitics associated with the connection to an off-chip inductor could degrade overall circuit performance
"
[Reference: https://www.quora.com/Why-are-inductors-not-used-in-integrated-circuits]

Note to self:
Quality factor, Q, for inductor is X_L/R therefore low quality factor would mean a high winding resistance and/or low inductor reactance due to weak magnetic field.

"They certainly can be. The problem is that they're not very well behaved. They are only used where absolutely necessary. For low frequencies, they're pretty much out of the question as they would be too large. For RF, they are used regularly to build filters and baluns and what not."
[Reference: https://electronics.stackexchange.com/questions/156353/why-inductors-can-not-be-integrated-into-ic]

PDF "On-Chip Spiral Inductors for Silicon-Based Radio-Frequency Integrated Circuits": https://drive.google.com/open?id=19eiwzoR51o-SSmw0qxfHSb92Ul7V4QYf or use this link for the same PDF: http://www-smirc.stanford.edu/papers/Orals98s-cpyue.pdf



Info about gyrator:
"In 1948 [Bernard Tellegen] postulated the gyrator. While you can’t buy one as a component, you can build one using other components. In fact, they are very necessary for some types of design. Put simply, a gyrator is a two-terminal device that inverts the current-voltage characteristic of an electrical component. Therefore, you can use a gyrator to convert a capacitor into an inductor or vice versa.

Keep in mind, the conversion is simply the electrical properties. Normally, current leads voltage in a capacitor and lags it in an inductor, and that’s what a gyrator changes. If you use a gyrator and a capacitor to make a virtual inductor, that inductor won’t magnetically couple to another inductor, real or simulated. There’s no magnetic field to do so. You also don’t get big voltage spikes caused by back EMF, which depending on your application could be a plus or a minus. But if you need an ungainly inductor in a circuit for its phase response, a gyrator may be just the ticket.
"
[Reference: https://hackaday.com/2017/07/06/gyrators-the-fifth-element/]

"A gyrator can be used to transform a load capacitance into an inductance. At low frequencies and low powers, the behaviour of the gyrator can be reproduced by a small op-amp circuit. This supplies a means of providing an inductive element in a small electronic circuit or integrated circuit."
[Reference: https://en.wikipedia.org/wiki/Gyrator#Simulated_inductor]
 
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