Time Travel and Temperature Guardbanding

Time Travel and Temperature Guardbanding–now those are two phrases rarely juxtaposed.  I googled them: “Your search – “Time Travel” and “Temperature Guardbanding” – did not match any documents.” No surprise.

So I was in Australia last week working with a client , helping them productize a really nifty technlogy (does anyone say nifty anymore?).  My daughter, who has a friend in New Zealand, told me I woud be time travelling.  She was right: when I flew home I left Sydney at 10:15 AM and arrived in LA at 6:30 AM.  The fellow in the cramped seat next to me in economy (do any productization folks get to fly business class, or are you all in the back with us? ) told me his young god on had asked him if he already knew the score for that night’s World Cup match.  So it’s not just me.

To the point (jet lag can be numbing), have you ever had a desire to travel back in time and fix an engineering mistake you made?  Me, I remember one of my first design projects, a solid-staterelay back when that was novel.  I had a patent on a revolutionary design topology and designed a part that was cheap, fast and reliable.  Just one nano problem–I flunked gaurdbanding for temperature.  The part worked great except at the extremes of its temperature range, where physics took its toll and performance plunged.  We came up with some work arounds but at the end of the day the product was flawed for want of a couple of additional components that would have added fractions of a penny to the costs, at least until we were able to do a redesign (which never happened because the company bellied up, but that’s another tale).

The tie in here is one of the problems that we are helping this customer in Australia solve, without having to rely on time travel technology, is to redesign the circuitry to properly guardband for the temperature extremes it will see in operation.  Which means that the design window is a bit smaller than was originally assumed, and there will be a cost in terms of power consumption and maybe even BOM cost if we are not proactive about fixing this ahead of time, instead of waiting until after the fact and then wishing for a chance to time travel.

The moral of this story: either take care in the design ahead of time and properly guardband for temperature (and power supply voltages and other tolerances), or invent time travel

If you do invent time travel, please call me–I’d like to be your first investor (or at least go back in time far enough to short BP…).

No worries.

Chuck

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