Are Integrated Analog Devices Perfect? Should They Be?

Read the following two statements, and think about which one more closely represents the way you work — and what you believe, if that's not the same thing.

  1. Perfection is the enemy of good enough.
  2. Good enough is the enemy of perfection.

Chances are that you have quoted or have been quoted one of these. The conflict facing many engineers is that, though their manager will want them to do (and/or spend) no more than is needed to meet the spec, they themselves will want at least to learn some new technique during the work, perhaps push some figure-of-merit boundary a little bit, and feel proud of what they've achieved at the completion of the project.

As a result, the manager's view of design paradigms, and vendor approaches to delivering them, might differ significantly from the engineer's view. The relevance to the integration debate is obvious. Fixed-function integration — for instance, combining all the blocks needed to create a multichannel ultrasound front end on one chip — is the electronics industry ecosystem's way of saying, “Look, buddy, this function has gone mainstream, so henceforth it's a waste of your valuable time to design it yourself. We've taken good enough and put it in a box for you.”

That's a rather disappointing response if you're the kind of engineer who relishes the challenge of designing an ultrasonic front end that's just a bit better than your competitor's. Some people just prefer to be at the leading/bleeding edge. It's the part of the tool that wears out the fastest, but it also does the most useful work.

Metaphors aside, there is a more serious concern about reliance on someone else's assessment of what is needed to do the job. Meeting the spec is all very well, until someone realizes that the spec was flawed. Earlier in my career, I spent the best part of two years getting a device to work to its spec, only to find that the spec could never have met the market requirements.

Once the level of integration has reached good-enough-in-a-box status, there is a risk that management might infer a reduced need for broader analog skills. Naturally, I'm biased, but the reduction in the availability of those people with a nose for when things are going awry in the signal path represents a clear reduction in organizational resilience.

Reconfigurable devices, which take blocks normally deployed as external components and integrate them into a fabric where they can be connected up and programmed in many different ways, still offer plenty of scope for the analog systems engineer. I'll return to distinctions between fixed-function and reconfigurable integration in later blogs. But there's still a substantial overlap, and the programmable SoC products I work with do find many uses that require little more than a drag-drop-compile design process.

And this ease of design can lull management into thinking that engineering skill is less necessary. I discovered that just this week. I was showing a customer some sensor conditioning done on our latest simple programmable system-on-chip devices. We left some stuff out to serve more economical applications. In the front-end differential stage required for a bridge transducer, I needed to use some external resistors to set the gain, because we haven't fitted an internal resistor network this time. “No good,” the customer said. “If it needs external resistors, it needs an analog engineer, and that costs me more than an ordinary engineer.” Actually, he said it in Japanese, but that was my colleague's translation.

I found it a bit depressing that the customer didn't think an ordinary engineer would be able to calculate three resistor values and tell the layout guy where to place them. These were basically the only external components. OK, I put small caps across the feedback resistors (to be in control of the bandwidth), but are we really teaching our new engineers so little? That's another blog topic in itself. Tell me what you think.

11 comments on “Are Integrated Analog Devices Perfect? Should They Be?

  1. Scott Elder
    June 17, 2013

    Hi Kendall —

    I can understand the perspective of your disgruntled customer.  Those pSoCs are advertised as drag and drop GUI products just like you wrote.  So when you tell someone they have to pick up a soldering iron, you've changed the rules of the game.  Kind of like a bait and switch.  [Here's the price of the new car….can I also sell you some tires…you know…you're going to need them.]

    Isn't that a reasonable position to take as a customer who comes in the door thinking drag and drop?

    When one starts adding caveats I know I start to get nervous.  Like you wrote.  First it was resistors.  And then it was some caps around the resistors.  Pretty darn soon…what's the point.  I'll just get an analog engineer to design the circuit from scratch and at least I save some money on parts.

    I think the pSoC products are to get rid of the analog engineers, no?

  2. Netcrawl
    June 17, 2013

    @kendal I may agree with you, you have a good point here. The ease of design would provide some great help, all projects benefits great from the ability to visualize the design,a n engineer should always be able to check the design constantly and closely. Tha ability to get closer and move faster that's exactly what design doing for us, it doesn't make engineering skill less necessary, it only make things much better and faster.   

  3. Brad Albing
    June 17, 2013

    @Scott – for you and me, it's no big deal to pick a resistor value and pick up the soldering iron. But as you noted, some other folks may not find it so easy to do. So I would agree with your understanding of the customer's point of view.

    June 18, 2013

    With the customer complaining that an analog engineer is needed to select the resistor, I see two fundamental problems.

    1. It is a shame that a manager cannot trust basic number crunching to the engineers he  has. Even if all he has are digital guys, even they should have had the basic electronics training to perform resistor selection. Otherwise, I would question the schooling provided.

    2. I believe that any application note should include not only the necessary parts, but other sundry parts that make the design work as a whole. For example, an ac-dc power supply design should not just show the front-end full-bridge rectifier, but also some of the other necessities that are part of ac protection such as MOVs, etc. Though not part of the chip directly, it would clue in the design engineer to think about the other aspects. And the application note should call this stuff out as well. Thus an engineer can see the number of parts required outside the basic chip design and not get surprised by, “Oh, and you will need this to protect this condition, and this to do that, etc.”

  5. kendallcp
    June 18, 2013

    I didn't grow up in the US, but in the UK, where we don't have the term 'bait and switch'.  But I know what you mean, and I don't think it applies here.  The customer is already using the more highly integrated part and is pleased with it, not disgruntled at all.  I wasn't trying to reel him in then get him to grudgingly design in a more expensive device. Just provide him with a broader set of options for future less sophisticated designs.

    Integration, in the sense we're discussing, exists on a continuum.  It's not an either-or thing, there are degrees of it  The question “what use is an op-amp without resistors?” is like the “what use is half an eye?” challenge beloved of objectors to the concept of evolution through selection.  The answer is, “a darn sight more useful than none at all”.

    I mixed my messages in the piece; really, I was trying (imperfectly…) to get across the notion that perfection can be a slippery, misleading concept.  Another random analogy prompted by something I did this morning.  If an adhesive sets too hard, sometimes the joint will break under stress.  It's better if it retains a little flexibility, or even repositionability.  Trading off perfection=rigidity for acceptability=flexibility might save you from an unexpected failure.

    Good discussion!

  6. eafpres
    June 18, 2013

    Having been both an engineer and a manager and a few things in-between, I can sympathize with both views–the engineer thinks it isn't ready, the manager wants to get it out the door.  Over 30 years of this, I conclude that managers serve a valuable function in drawing a line in the sand.  Otherwise, most engineers would never “ship it”.  Engineers can learn to flourish in such an environment–if you have a good manager, she/he will listen to your thoughts and ask questions about risk, time, cost, product features, etc. and make a good decsion on “in or out” for the features.  It helps a lot if the manager has a technical background…

    In a past company, we did mostly custom designs of antenna solutions for various, often mobile applications.  We set up every project with a PM and a cross-functional team drawn from the staff.  Required members were the sales person who sold the design to the customer, a mechanical engineer/designer, and RF engineer, a quality engineer (usually from manufacturing), a manufacturing engineer, purchasing/supply chain, and production.

    In this setup, the sales person was responsible for the customer requirements.  However, it usually worked that the sales person got the opportunity for engineering to go in an close the deal.  Then the ME & RF folks on the team “owned” the requirements.  This was good/bad news becuase this open relationship with the customer sometimes created an open-ended view of the specs–the farther along the project progressed, as both sides learned more, the more stuff got added into the spec.  Once I was a manager, I had to intervene and manage expectations quite often, otherwise designs would never have been finished and nobody would have been happy.

  7. bjcoppa
    June 18, 2013

    How much of Cypress chips are outsourced to foundries these days? The Silicon Valley fab was sold off to AMD right? The main US fab is in Minnesota correct? Thanks for your input.

  8. goafrit2
    June 19, 2013

    Always get caught between Analog Devices as a company and analog devices as what we do. Many people now write analogue devices to differentiate it from the corporation to help clarity.

    Now on the question: are integrated analogue devices perfect? Not. They are never and they need not be. Nothing is truly perfect otherwise they wil not be tomorrow.

  9. goafrit2
    June 19, 2013

    >> But as you noted, some other folks may not find it so easy to

    It is never easy but with some of the latest mobile apps, that could be easy. But the challenge today is that we are still in the domain when the time to market in the industry is slow. It takes time to make physical device. That said, one has to understand and properly know the market before any investment.

  10. bjcoppa
    June 19, 2013

    Companies need to put chip design into perspective. The cost of building a brand new fab is escalating an alarming rate- up to $5 billion or more- for high-performance memory and logic ICs. Design costs are minimal in comparison. Software licenses pale in comparison to semiconductor equipment costs of ~$2 million per system.

  11. Brad Albing
    June 20, 2013

    @Derek, to point #1 – yes, one would think the boss could/would assume his engineers could be trusted to do the calculations and make it all work right. To point #2, in my former life as an apps engineer, I generally supplied the customers with all the info I figured they needed – as in your example. If they appeared to be novices in some design aspects, just like you suggested, I'd tell them to make sure they added extra components to insure a rugged design, etc. Good business practice to properly support the customer.

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