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The Gold Standard of Analog Circuit Prose

When I worked at Analog Devices, every new engineer received a package of materials on his first day of work. The package included several books edited by ADI's Dan Sheingold — the Data Conversion Handbook , the Non-Linear Circuits Handbook , and later the Transducer Interfacing Handbook — plus the most recent issues of Analog Dialogue.

Sheingold is retiring next month, and I recently attended his farewell party.

It is not an exaggeration to say his writing instructed and influenced multiple generations of analog engineers (both uppercase Analog and lowercase analog). He has spent more than 60 years at his craft — the first 19 at George A. Philbrick Researches and then 44 years at Analog Devices. For his efforts, he was recognized as a Fellow of the IEEE “for contributions to the understanding and use of analog devices and data converters.”

To quote Dave Kress, Sheingold “taught so many of us that writing about very technical information does not provide an excuse for bad writing; rather, good writing does a better job of engaging the reader and conveying the technical information you are presenting.”

His writing style is exemplary. When he was at Philbrick, the titles of his works included The Lightning Empiricist and the Philbrick Applications Manual for Computing Amplifiers for Modeling, Measuring, Manipulating and Much Else . Who could resist reading this stuff?

And this one-page sheet of simple op-amp application circuits (created by Sheingold) was taped to the wall of every analog engineer's office I saw in my early years in the business.

The Philbrick wall chart showing every circuit you'd need to do a proper analog design. (Source: George A. Philbrick Researches
Archive)

The Philbrick wall chart showing every circuit you'd need to do a proper analog design.
(Source: George A. Philbrick Researches Archive)

His career spanned the entire life (so far) of the analog circuits industry. Philbrick produced the first integrated op amps, plug-in devices with two 12AX7 dual-triode vacuum tubes sprouting from the top. These are the prehistoric ancestors to modern op amps, complete with the standard eight-pin footprint.

A typical Philbrick op-amp with its cheery red glow. (Source: Wikipedia)

A typical Philbrick op-amp with its cheery red glow.
(Source: Wikipedia)

The K2-W used power supplies of +300V for the tube anodes, -300V for the cathodes and grid bias, and 6.3VAC (or DC) for the filaments. It delivered 100kc (kHz) of bandwidth and an open-loop gain of 15,000 while driving +/-50V into a 50k load resistance.

The schematic for the K2-W, in case you want to build your own. (Source: George A. Philbrick Researches Archive)

The schematic for the K2-W, in case you want to build your own.
(Source: George A. Philbrick Researches Archive)

As time went on, Philbrick's product line evolved into packaged modules built from discrete transistors, including op amps, A/D and D/A converters, and V-F converters. One of the design engineers of that era was the analog legend Bob Pease, who later plied his trade at National Semiconductor and carried on the tradition of excellent writing about analog circuits.

At ADI, Sheingold used the pages of Analog Dialogue to chronicle his company's (and industry's) technological transitions from assembled discrete op-amp modules and converter modules to monolithic amplifiers, analog multipliers and function circuits, converters, and onward into power management, RF, and DSP. It is worth noting that Analog Dialogue has had only three editors since its first issue in 1970: ADI founder and chairman Ray Stata, Dan Sheingold, and now Scott Wayne.

At 84, Sheingold is doing well and doing good. He has been volunteering with Learning Ally, an organization that produces audio versions of everything from grade-school textbooks to graduate-level technical material for visually impaired or reading-impaired students. The group uses volunteers like Sheingold to read technical texts and verbally describe things like diagrams and schematics. It seems like a worthwhile cause. Learning Ally could use both volunteers and donations. Tell them Dan Sheingold sent you.

The only three editors of Analog Dialogue (left to right: Dan Sheingold, Ray Stata, and Scott Wayne).

The only three editors of Analog Dialogue (left to right: Dan Sheingold, Ray Stata, and Scott Wayne).

7 comments on “The Gold Standard of Analog Circuit Prose

  1. Michael Dunn
    February 15, 2013

    Happy owner of the Nonlinear Circuits Handbook. And a Philbrick Applications Manual.

    Volume 1 #1 of Analogue Dialogue is April 1967 according to my Best of  compilation 🙂

  2. Bill_Jaffa
    February 15, 2013

    I worked for Dan for 6 years as ass't editor of Analog Dialogue. Besides being a great person, he taught me that clarity of expression about a design or product–whether in writing or orally–comes from two things: 1) understanding what you're writing or talking about and 2) clear thinking, no cliches, no internal vaguenss. In other words, you can't be clear to others if you are not first clear and comfortable about it first in your own mind. Sounds obvious, but to work that way each day was a fabulous learning experience. I also learned that resorting to tired cliches in writing was laziness on the author's part and did not serve the audience well!

  3. Brad Albing
    February 26, 2013

    Back around 1970, having seen the Philbrick Apps Manual, I wanted to experiment w/ one of the 12AX7-based op-amps as a guitar preamp.

  4. wawaus1
    February 27, 2013

    Is it possible to get a copy of that OP-Amp wall chart?

  5. Doug Grant
    March 4, 2013

    Since Philbrick is long gone, it has been out of print for a long time. You can find a good scan at philbrickarchive.org and print it yourself.

  6. wawaus1
    March 4, 2013

    Thank you Doug, that is very helpful.

  7. DEREK.KOONCE
    March 5, 2013

    The Philbrick website is very informative. Though 99% is out of date, the basics is still there and would be great reading. I printed the chart out and stuck it up on the wall in my office/lab. Be interesting to see how all the mechanical engineers react to it – I work in a company where I am the only EE. I am the black art dude in the company to them. haha

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