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Am I Cut Out to Be an Analog Designer?

In college, we were taught analog design, RF design, high-power design, and digital design. To me, digital was so much simpler. You could forget about things such as voltage and current, sensitivities, and so many other factors. With analog, the idea of putting, the signal processing, power, and RF(!) all on the same piece of silicon seemed impossible.

Abstractions appeared to work, in that you could abstract transistors in specific configurations to become primitive functions, such as AND gates. Those gates were packed up into regularly performing functions such as those provided by Texas Instruments in its 7400 family. So long as you conformed to loading limits, you only had to consider “1” and “0,” and if you really needed to mix logic types like TTL and ECL, you used converters between the blocks.

By the time I graduated college, I almost knew the 7400 series by heart and only had to consult the manual every now and then to check on pin assignments, etc.

Those abstractions enabled me to design bigger things. I could design a whole computer in a day and didn't have to fiddle around with checking corner cases and deal with component selection or to make sure the tolerance of the resistor I specified would work. A single day! I could load it up in a simulator, using readily available models, or could construct the models fairly easily if they had already been created, and quickly iron out the most fundamental problems. Running the software would find the rest of the problems after it had been built. I can't imagine being able to do an analog design in such a short time – if at all.

My first computer was constructed using printed circuit boards I made myself with a solid copper sheet and acid etch. I guess it was at about 1/8″ to 1/4″ geometry. For the ones I couldn't route, I used wires, and, yes, it looked a mess by the time I was done, but it worked.

It ran my own operating system, Brian's Operating System (The BOS). I had problems with only one part of the whole design — designing and building the interface to the cassette tape recorder, which was where my software was stored, my bulk storage. I basically just used a dual tone to record my ones and zeros and added in a few parity bits. That was a clear indication to me that I did not have what it took to become an analog designer.

For the next 30 years I was happy that analog was off in the distance. Data was converted into digital, and then I could work with it and hand it back to DACs at the end. But as designs employed smaller nodes, and extreme cost pressures led to the requirement for analog and digital to come onto the same die, it became impossible to ignore it any more. Luckily, by that time I was no longer designing chips. With little at stake I quickly came to realize how “greedy” digital circuitry is. It really is not a very good citizen. Also, many of the choices made in process technologies are for the benefit of digital and not analog.

In my blogs, I will be looking at the world of analog and digital and, most importantly, the impact they have on each other. How can they be made to play nicely with each other, what are the problems, what fixes exist, what fixes should exist? How are processes evolving so we can faster enable the integration of more analog functionality onto a piece of silicon?

This is my goal here on Integration Nation, so while scanning the horizon for new developments, I am all ears too. What are you hearing? What do you want to hear about? Just leave a comment here or start your own message thread. Either way, my electronic door is always open, and I invite all of you in.

Let the fun begin!

15 comments on “Am I Cut Out to Be an Analog Designer?

  1. RedDerek
    March 18, 2013

    It used to be that for fast processing, analog was the method. Digital, with the faster processors is allowing for some replacement. Still, the world is analog despite people saying it is a digital world. Power supplies are just starting to become digital since there are advantages such as adjustment of the control loop for better efficiency from low power to high power. This is possible due to the faster and faster chips. There are still limitations on the switching speed since it takes some time for digital to react versus analog. Analog power supplies are operting in the MHz range while the digital supplies are operating in the 100's kHz.

  2. Comfortable
    March 18, 2013

    I'm a little skeptical about digital power.  There has been over $100 Million in VC money invested over the past 10 years and I've not seen a survivor yet.  FyreStorm, Integral Wave Technologies, Primerion, and one other name I don't remember.  I'm sure there are others.

    As far as getting into Analog, when I was going to college I worked for a design company that was producing Intel X86 systems.  The design method was to simply copy the provided schematics and start writing code.  My thinking at the time was why in the world would I study Calculus and Semiconductor Physics to then just copy a schematic.

    A little naive perspective given how DSP has become so important in analog signal processing, but hey…I was about 20.

  3. amrutah
    March 18, 2013

    Everybody needs to be an Analog Designer now or I can say every body needs to know the intricacies of Analog Design. Since the process techonologies are shrinking, power supply are reduced and high frequency operation are making a digital signal resemble an analog signal.

      And when it comes to system simulations of ICs the mixed mode simulations are needed not just analog or digital simualtions.

  4. Netcrawl
    March 19, 2013

    @Comfortable, we're living in a digital world, where everything from communications to office tools, they're all digital. Its a new world, we need keep moving, move one step higher- digital is the next platform-its the future.

    Have you watched those CNN coverage of US militray's strike in Iraq and Afghanistan, those prescision strikes are made possible using digital tools, from GPS to communication links, almost everything, they're all using digital.     

  5. SunitaT
    March 19, 2013

    Since the process techonologies are shrinking, power supply are reduced and high frequency operation are making a digital signal resemble an analog signal.


    @amrutah, I totally agree with your point. I think we cannot ignore Analog domain anymore. Digital designer need to look at analog aspects as well when they are working on digital designs. But things become even more complex when you have both digital and analog modules on the same chip and it would be a challenge for  he desingers to study the impact of analog on digital and viceversa.

  6. SunitaT
    March 19, 2013

    I will be looking at the world of analog and digital and, most importantly, the impact they have on each other.

    @Brian, thanks for touching upon this topic. Mixed signal design is one of the most complex things to understand and implement. We are eagerly looking forward for your blogs on this topic.

  7. Comfortable
    March 19, 2013

    @Netcrawl – I'm not sure I understand your point.  There was $40 Billion USD sold in analog semiconductors in 2012.  This year the growth rate will be 9.5% UP not down.

    I would encourage you to study the analog semiconductor market a bit more and perhaps you might see that these two technologies will coexist for many, many years to come.  Neither technology is going away anytime soon.

    Last night I watched a TED video on my laptop using an analog touchpad, watching vivid colors made possible by an analog LED backlight driver, all while listening to the audio from an analog data converter through an analog headphone driver.  Thank goodness the analog battery charger was able to work with those 1s and 0s coming out of my 120V AC wall socket. 🙂

     

     

  8. Brad Albing
    March 19, 2013

    I understand your skepticism re digital power. But I think there are a few manufacturers who are just now (i.e., over the last year) gaining a real understanding of what is needed in a digital controller, who are the potential buyers, and where it's being used. So you'll start to see it used in applications from POL regulators to the very large and sophisticated server power supplies (i.e., blade servers, redundant supplies, supplies that do status reporting and can have their firmware updated while in use; pro'ly a blog in there…).

  9. Comfortable
    March 19, 2013

    @Brad.   Ah!  You helped me remember.  Zilker Labs was the fourth one.  Acquired by Intersil in Dec 2008.

    Re: digital power – I think it really depends upon what one means by digital power.  As a status monitor/reporting tool?  Absolutely makes sense.   In the control loop, with ADCs and DACs?  I just don't see the value proposition yet.  But I always like to see new approaches and how they solve old problems for lower cost or higher performance.  So we wait and see.

  10. Brad Albing
    March 20, 2013

    Hi Brian – I will be interested to see where you take this – especially with your design background. Should provoke some good discussions.

  11. BrianBailey
    March 20, 2013

    Hi Brad – it will indeed be interesting. Sometimes a fish out of water can stir up some interesting discussions, and I am not afraid to put my toe in the water and see how many fish bite.

  12. jkvasan
    March 23, 2013

    Hi Brian,

    Nice post kindling a lot of old memories. Between late 80s and early 90s I was involved in full-time analog design. I was working on vacuum tube based AM radios. We used to assemble and service and work on designing multi-band radios. When transistor radios were introduced, actually, it was like a slap on the face. No more fear of shock, voltages not more than 6 Volts. Most of all nothing to be soldered on the chassis. By adjusting the rod type antenna and connecting a wire to the nearest window grill, we could receive several transmissions including the local walkie-talkies.

    Somehow I feel, the valve radio had a better frequency response than the transistor ones and the present highly integrated ones. 

    The line between analog and digital is quite a remarkable one and needs such discussions.

  13. Brad Albing
    March 27, 2013

    Yep – Zilker/Intersil. Some nice parts with some good Eval boards.

  14. Brad Albing
    March 27, 2013

    Sunita – of course, most of us regular readers here know not to ignore analog. It's the Others who are just now realizing that they must learn more.

  15. Brad Albing
    March 27, 2013

    There is a different sound from some of the old valve radios. I personally like it, tho' others will argue that the sound quality is not as good. But the quality sometimes must be evaluated with specs beyond mere frequency response. This could lead to a dsicussion of THD, IMD, adjacent channel interference, smooth limiting vs. clipping…. Another blog idea!

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