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Thread: Early integrated circuits

  1. #1
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    Default Early integrated circuits

    I came across this recently. In 1953 the US Navy ran project Tinkertoy to come up with a way to quickly build circuit modules. I likened these to an early form of integrated circuits. Enjoy.

    Will

  2. #2
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    Default Re: Early integrated circuits

    Very interesting!

    The film demonstrated the earliest development of a number of electronic assembly concepts.... some of which exist (in more modern form) today... others died along the way.

    The idea of using ceramic substrates with 'silvered' (i.e. conductive) regions does persist, today, but in dramatically different form; modern resistors and capacitors still depend on a ceramic substrate, and screen printing processes, but they are individual components, not multi-component devices.

    The printing of conductive traces on ceramic substrates to form sub-circuits did not survive... 'additive' circuit fabrication never did make it's mark... but the end of the film did show 'subtractive' circuit board design, which is the technology that eventually prevailed. Subtractive processes are what are used, today, to make circuit boards... copper-clad boards are covered with a photoresist, exposed through a pattern mask, cured, and then etched to leave circuit traces... this simple explanation fails to convey the sophistication of the modern PCB process, which can produce boards with dozens of layers, extraordinarily fine features, etc.

    Similarly, the idea of tiny stacked substrates never made it... but modularization certainly did, in somewhat different form. I guess the key advance was the development of the 'op amp', or 'operational amplifier', which is a generalized type of amplifier with exceptionally high open loop gain that can be tailored, with external components, for specific closed loop gain and bandwidth... much of that development came in the 60's, and the original op-amps were tube based. A fellow named George Philbrick was the pioneer of that technology... and my alma mater, Analog Devices, became a competitor in the late 60's... both companies were here in Massachusetts (Dedham, and Norwood).

    The 'notched' ceramic substrate did enjoy a period of popularity; tube-based Tektronix oscilloscopes were built using notched ceramic barrier strips, upon which, conventional components (resistors and capacitors) were mounted. When I started out my career in 1974, we were still using those old tube-based scopes... but more modern transistorized scopes were beginning to appear.

    Of course, 'integrated circuits' mean something entirely different, today. I did two integrated circuit projects, during my career, and frankly, did NOT enjoy the design process, which is highly dependent on computer simulation, since building a prototype is a very long and expensive process... I prefer discrete component design.

    Just to give you an example: when I started out, we were building a device called an 'analog to digital converter' (A/D converter), and a 16 bit A/D was 2" x 4" x 0.8", and sold for several hundred bucks. In my last big project, completed last year, I used a 16 bit A/D converter, about the size of a grain of rice, costing just a few dollars.
    "Reason and facts are sacrificed to opinion and myth. Demonstrable falsehoods are circulated and recycled as fact. Narrow minded opinion refuses to be subjected to thought and analysis. Too many now subject events to a prefabricated set of interpretations, usually provided by a biased media source. The myth is more comfortable than the often difficult search for truth."







  3. #3
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    Default Re: Early integrated circuits

    Quote Originally Posted by Norman Bernstein View Post
    ....Just to give you an example: when I started out, we were building a device called an 'analog to digital converter' (A/D converter), and a 16 bit A/D was 2" x 4" x 0.8", and sold for several hundred bucks. In my last big project, completed last year, I used a 16 bit A/D converter, about the size of a grain of rice, costing just a few dollars.
    CRT (CATHODE RAY TUBE)-screen oscilloscopes eventually evolved into LCD-screen oscilloscopes over the years, although I was unable to accompany these happenings due to my job assignment at the time.

    In the early 80īs, 8-bit A/Ds could be had at retailers for 'electronics afficionados' on Edgware Rd (North London) for a few quid (5-10 US dollars)...but they were slow (kHz) devices, and low precision.

  4. #4
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    Default Re: Early integrated circuits

    Building electronics today as a hobbyist for me means looking for modules such as Arduino and various breakout boards for displays such as the Adafruit OLED 128x64 p/n 938. It would be awesome though if I could fabricate a one off MPPT solar charge controller or a watthour meter on a fabricated IC chip. It will be interesting to see what the future brings here.
    Will

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