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Cascode emitter follower

What I was thinking of was Barrie Gilbert's chapter, "Where do the small circuits come from?" in "Analog Circuit Design: Art, Science, and Personalities", P. 179-180:

"How many distinctly different and really useful circuits can be made with two transistors, anyway? (Answer: about twenty-four). What heady heights of functional complexity can be reached with three, or even four, transistors? And heaven forgive us for being so gluttonous, but what might one do with _eight_ transistors?"

He didn't actually mention seven--you lose. ;)

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs 
Principal Consultant 
ElectroOptical Innovations LLC 
Optics, Electro-optics, Photonics, Analog Electronics 

160 North State Road #203 
Briarcliff Manor NY 10510 

hobbs at electrooptical dot net 
http://electrooptical.net
Reply to
Phil Hobbs
Loading thread data ...

...naturally, one counts capacitors, inductors, resistors, FETs, tubes, transformers, etc.

Reply to
Robert Baer

The only good that has come from them, is the royalties to the inventor.

Reply to
Robert Baer

Of course no white board! Does the copper clad and connectors count as parts?

7 parts might include most of the two transistor circuits.

George H.

Reply to
George Herold

Does the 24 include mixing bipolar with fets?

George H.

Reply to
George Herold

I meant a total of 7 parts. Everybody gets a sandwich-sized ziploc with the 7 parts inside. Maybe they furnish their own battery.

--

John Larkin         Highland Technology, Inc 

lunatic fringe electronics
Reply to
John Larkin

Why so many parts? One microcontroller with integrated everything, some decoupling...

Cheers

--
Syd
Reply to
Syd Rumpo

OK then, design us a >100MHz bandwidth,

Reply to
Jeroen Belleman

Actually with a microcontroller running spice, I possibly could _design_ such a thing :-)

Cheers

--
Syd
Reply to
Syd Rumpo

The objective would be to teach them about electronics - you know, controlling electricity - not how to type some artificial, arbitrary language.

It's absurd how technology is now mostly identified with coding. The giant software companies, aided by paid politicians, want to teach every schoolkid to code. I teach a few kids how to think about and design electronics. I bet my kids do better.

Sure, my guys can code too; anybody can do that.

--

John Larkin         Highland Technology, Inc 

lunatic fringe electronics
Reply to
John Larkin

Dunno. We should see how many we can find. This is what I came up with in ten minutes or so:

  1. Darlington
  2. Sziklai and other shunt feedback things
  3. Cascode
  4. Follower with tail current source
  5. Collector/drain bootstrap
  6. diff pair
  7. Cascaded common-emitter stages
  8. Common base plus follower
  9. Common emitter plus follower
  10. Cascaded followers
  11. Series connection for higher voltage
  12. Parallel connection for higher current
  13. Push-pull follower (class B)
  14. Push-push doubler
  15. Muting switch plus follower
  16. Current mirror
  17. SCR connection
  18. Royer converter
  19. Log converter with follower for temperature compensation
  20. Two-terminal current limiter

And then maybe some variations:

a. Series-shunt pair b. Schmitt trigger c. Eccles-Jordan flip flop d. White-style follower e. Exponential current source f. PNP level shifter (grounded base) plus follower g. .....

So what did I miss, everybody?

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs 
Principal Consultant 
ElectroOptical Innovations LLC 
Optics, Electro-optics, Photonics, Analog Electronics 

160 North State Road #203 
Briarcliff Manor NY 10510 

hobbs at electrooptical dot net 
http://electrooptical.net
Reply to
Phil Hobbs

...

...

I'd kinda call the 'cascaded followers' a dupe of Darlington. Not sure what a push-push doubler is,,,

This pairing doesn't come up often (but it'd handle sine-to-square converter needs, input capacitor coupled). Don't know how to name it.

**warning bad ASCII art*** (-)bias | +--- ----+--R--+ | V / | | ---+--/ |

| ---+--\ | | V | \ | +--- | ----+--R--+ | | GND (+)bias

Reply to
whit3rd

The difference is that the two collectors needn't be connected together. One can argue about that, I suppose. A replacement might be

  1. Phase splitter plus follower. That gives +/- phases with about the same drive impedance and reduces phase funnies.

A push-push doubler has the bases driven in phase and the collector currents in push-pull (i.e. subtracted using a centre-tapped transformer). The symmetry ideally gets rid of the fundamental and odd harmonics.

Cute. That's sort of the push-push circuit, but run sideways and used like a diode clipper.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs 
Principal Consultant 
ElectroOptical Innovations LLC 
Optics, Electro-optics, Photonics, Analog Electronics 

160 North State Road #203 
Briarcliff Manor NY 10510 

hobbs at electrooptical dot net 
http://electrooptical.net
Reply to
Phil Hobbs

That can be done all-NPN... I did this...

for a smog controller chip at Philco-Ford, Santa Clara, in 1968 ...Jim Thompson

--
| James E.Thompson                                 |    mens     | 
| Analog Innovations                               |     et      | 
| Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    | 
| San Tan Valley, AZ 85142   Skype: Contacts Only  |             | 
| Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  | 
| E-mail Icon at http://www.analog-innovations.com |    1962     | 

             I'm looking for work... see my website.
Reply to
Jim Thompson

Two transistors, remember!

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs 
Principal Consultant 
ElectroOptical Innovations LLC 
Optics, Electro-optics, Photonics, Analog Electronics 

160 North State Road #203 
Briarcliff Manor NY 10510 

hobbs at electrooptical dot net 
http://electrooptical.net
Reply to
Phil Hobbs

Just remove Q3, but you won't get a flat baseline. ...Jim Thompson

--
| James E.Thompson                                 |    mens     | 
| Analog Innovations                               |     et      | 
| Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    | 
| San Tan Valley, AZ 85142   Skype: Contacts Only  |             | 
| Voice:(480)460-2350  Fax: Available upon request |  Brass Rat  | 
| E-mail Icon at http://www.analog-innovations.com |    1962     | 

             I'm looking for work... see my website.
Reply to
Jim Thompson

Now you got me curious. What did that go in ? Were there ECMs in cars in California back then ? I know electronic ignitions existed, and i fact had for about ten years, but were not in common use.

Reply to
jurb6006

Den torsdag den 21. juli 2016 kl. 18.00.45 UTC+2 skrev John Larkin:

anybody can use a hammer and saw, that doesn't mean you'd want just anybody to build you a house

-Lasse

Reply to
Lasse Langwadt Christensen

Well You are going to be much better at that game than me. (most of the time I need an opamp to help me with my transistor circuits. :^)

OK, I'm printing that out and I'll try and draw what I think you mean, (it will be a few days... I've got a workshop thing to run.)

George H.

Reply to
George Herold

I'd add

same drive impedance and reduces phase funnies.

  1. Two-stage cap multiplier (a fave)

g. NPN/PNP emitter follower to more-or-less get rid of the offset. (Cascaded followers really want to oscillate, though.)

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs 
Principal Consultant 
ElectroOptical Innovations LLC 
Optics, Electro-optics, Photonics, Analog Electronics 

160 North State Road #203 
Briarcliff Manor NY 10510 

hobbs at electrooptical dot net 
http://electrooptical.net
Reply to
Phil Hobbs

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