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Am I right in thinking the 741 was.....

1) Some sort of weirdo f*ck up invented to demonstrate the designers ability to be clever.

2) Some sort of weirdo f*ck up invented by the designer after management stuck the oar in because the original design was just too simple and they wanted everyone else to have a hard time ripping it off.

3) It makes obvious sense given the constraints of processing at the time it was designed.

4) It's just obvious!

5) The designer was the only person who could come up with this shit at the time but drank beer down the pub with his mate(s) and they hatched a plan for the gradual release of shit to different companies.... at a price.

DNA

Reply to
Genome
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You alright there, DNA?

(1) The 741 wasn't too shabby an OpAmp (for its time).

(2) The published schematic is NOT the real schematic... ask (IIRC) Raytheon... they copied the schematic with disastrous results ;-)

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
|  Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    |
|  Phoenix, Arizona            Voice:(480)460-2350  |             |
|  E-mail Address at Website     Fax:(480)460-2142  |  Brass Rat  |
|       http://www.analog-innovations.com           |    1962     |
             
I love to cook with wine.      Sometimes I even put it in the food.
Reply to
Jim Thompson

"Jim Thompson" wrote in message news: snipped-for-privacy@4ax.com...

That narrows things down.....

So, is

formatting link

slightly right in the right sort of way?

Did Bill and Ben have their heads together when Mike gave Raytheon the original design but they upset Mike and Mike met Bill who spoke to Bob and then Ethel came up with the master plan whereby Bob, Bill, Martin, Mike and other Bill edited the masks to come up with something entirely different.... but made up another diagram and then spoke to Dave and other Mike about an offer for second sourcing on a particular understanding that certain things would not happen as long as certain other things did....?

Sure fine, I just felt stupid enough to try and figure out why and then thought I'd check for hidden (conspiracy theories) reasons unrelated to my limited comprehension of 'this bit goes up, so this bit goes down'.

DNA

Reply to
Genome

How DARE you insult Mr.Rube Goldberg with such a demeaning language!

-- Paul Hovnanian mailto: snipped-for-privacy@Hovnanian.com

------------------------------------------------------------------ A limerick packs laughs anatomical Into space that is quite economical. But the good ones I've seen So seldom are clean, And the clean ones so seldom are comical.

Reply to
Paul Hovnanian P.E.

Reply to
zhangleia

IIRC that looks correct. I used a lot of those in thick-film hybrid LDO regulators for the Hughes TOW Missile in 1970-73. I needed that exact configuration to make it work. Other _so-called_ 741's wouldn't work.

That's a common-mode feedback loop in the middle (if that Q8-Q9-Q3-Q4 circuitry is throwing off your comprehension). Q10-Q11 is your classic Widlar logarithmic current mirror.

Do I need to write another OpAmp tutorial?

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
|  Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    |
|  Phoenix, Arizona            Voice:(480)460-2350  |             |
|  E-mail Address at Website     Fax:(480)460-2142  |  Brass Rat  |
|       http://www.analog-innovations.com           |    1962     |
             
I love to cook with wine.      Sometimes I even put it in the food.
Reply to
Jim Thompson

Wouldn't dream of it and I'm sure he would deny it anyway.

DNA

Reply to
Genome

"Jim Thompson" wrote in message news: snipped-for-privacy@4ax.com...

No!!! And I don't need none of your silly hints either.

For the moment it might be enough to say it is meant to be..... I'll be off to bed now but I shall move things up and down tomorrow.

DNA

Reply to
Genome

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
|  Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    |
|  Phoenix, Arizona            Voice:(480)460-2350  |             |
|  E-mail Address at Website     Fax:(480)460-2142  |  Brass Rat  |
|       http://www.analog-innovations.com           |    1962     |
             
I love to cook with wine.      Sometimes I even put it in the food.
Reply to
Jim Thompson

Or his design review by Mr Murphy.

--
Service to my country? Been there, Done that, and I've got my DD214 to 
prove it. 
Member of DAV #85. 

Michael A. Terrell 
Central Florida
Reply to
Michael A. Terrell

I remember, in days of yore, making the decision to use 741's in a big shipboard control system program. They were more expensive than uA709's and such, burger+fries+milkshake maybe, but had three big advantages: no front-end zenering/latchup modes, no external compensation, and a decent current limit. That sort of stuff was impressive in those days. They were fine for most analog/controls stuff, had few quirks and pretty good DC specs. The PNP front-end had chronic popcorn noise, so they sucked for really low-level stuff.

What's a good gp opamp now? I like the LM7301, SOT-23, r-r i/o, OK DC specs, 4 MHz, 5v to +-15v supplies.

John

Reply to
John Larkin

Hello John,

I liked the uA709 better. Compared to the 741 it felt like a hotrod but that also meant you could wreck out easier. Of course, the hottest of all amps from those days is the uA733 which was also remarkably cheap almost right from the start. I made a lot of RF gear with those. There were times when a 733 sold for about the same price as a 741 in the local stores (in Germany) but you got a Kawasaki instead of a moped.

Nice, but expensive.

--
Regards, Joerg

http://www.analogconsultants.com
Reply to
Joerg

Wasn't the µA733 an early video amplifier?

--
Service to my country? Been there, Done that, and I\'ve got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida
Reply to
Michael A. Terrell

balanced out, but only +/-6V supply

--
ciao Ban
Apricale, Italy
Reply to
Ban

What's a modern-day replacement for NE5532?

SioL

Reply to
SioL

"Jim Thompson" wrote in message news: snipped-for-privacy@4ax.com...

So, it was item 3.

I'll make no claims but, after a bit of head beating, I see something. Shit, now you've told me, I can't even claim to have almost got nowhere.... Bastard. Now all the Girlies down the pub want to meet the real Jim Thompson.

DNA

Reply to
Genome

Sure they do. One of the worst put-downs I ever endured was from a _very_well_put_together_ female employee who told me I was "a father image" to her :-(

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
|  Analog/Mixed-Signal ASIC\'s and Discrete Systems  |    manus    |
|  Phoenix, Arizona            Voice:(480)460-2350  |             |
|  E-mail Address at Website     Fax:(480)460-2142  |  Brass Rat  |
|       http://www.analog-innovations.com           |    1962     |
             
I love to cook with wine.      Sometimes I even put it in the food.
Reply to
Jim Thompson

Stings, don't it? I can still remember the first time a gal on the street called me "sir". 8-(

Best regards, Spehro Pefhany

--
"it\'s the network..."                          "The Journey is the reward"
speff@interlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com
Reply to
Spehro Pefhany

Youngster. I've been called "sir" for at least 25 years ;-)

And "N" has finally succumbed to using the "senior" discounts.

I've been using them for years. To me a discount is a discount... I don't care what you call it.

The airline senior discount can be quite substantial... I don't tell them I'm a working senior... the laptop is "just for watching movies" ;-)

...Jim Thompson

--
|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
|  Analog/Mixed-Signal ASIC\'s and Discrete Systems  |    manus    |
|  Phoenix, Arizona            Voice:(480)460-2350  |             |
|  E-mail Address at Website     Fax:(480)460-2142  |  Brass Rat  |
|       http://www.analog-innovations.com           |    1962     |
             
I love to cook with wine.      Sometimes I even put it in the food.
Reply to
Jim Thompson

Gosh Jim, are there chip-designer groupies?

John

Reply to
John Larkin

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