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An unfortunate side-effect?

There's a chip shortage.

No, I'm not talking about your favourite crinkle-cut salt and vinegar tasty delight from Bluebird. I'm talking about integrated circuits and other components fabricated from silicon.

In fact, there's a general shortage of electronic components that goes beyond LSI devices, right down to things like capacitors, transistors and diodes.

This shortage is causing manufacturers some real issues -- both within and outside the realm of the traditional electronics industry.

Some car makers, for example, are unable to roll $50,000 vehicles off the assembly line for lack of what used to be a $0.30 microcontroller device. That's a real problem.

However, there's another problem that may well be a nightmare for consumers.

I'm talking about the effects of component substitution and product revisions that take place to allow for non-compatible substitutions.

When a decent electronics designer gets to work, they craft up a system with due regard to balancing price and performance.

As a trained design engineer, I was taught to allow an "overhead" into the selection of components. This was done for a variety of reasons but mainly to ensure the reliability and longevity of the product.

For example, if you used a resistor which, in normal operation, had to dissipate half a watt of energy you would not specify a half-watt component in the final BOM (bill of materials). Instead you'd specify a part that had sufficient headroom to allow for sustained use at the top end of environmental and operational parameters.

Sure, in theory a half watt resistor would work just fine most of the time and would likely be cheaper than a 1 Watt device. However, continuous running at full load in the middle of an extremely hot summer would likely push that nominal half-watt device beyond its limits and could result in premature failure -- hence the extra work was done to determine the "worst case" and allow some extra so as to extend the MTTF (mean time to failure).

Unfortunately, today's component shortages are perhaps pushing manufacturers to reduce or even completely eliminate the sensible overhead when selecting components for a design. When the originally specified device is not actually available there is obviously a temptation to use something "almost as good" and then ship the device with your fingers crossed.

Sometimes that works and everything continues to operate as planned, other times it doesn't and the lesser device fails prematurely with resultant problems.

I think we might be seeing a very good example of this with the GP-P750GM and GP-P850GM computer power supplies from Gigabyte.

This video is well worth a watch:

As you can see, these PSUs seem to have a significant reliability problem. Although this can be attributed to a design flaw (inadequate over-temperature protection) it may also be that the switching FETs that seem to fail have been substituted with an under-spec'd device as a result of supply shortages.

I've seen a number of other electronic devices undergoing small redesigns recently due to parts shortages and in at least a few cases this has resulted in a product that performs nowhere near as well as the original. Perhaps the manufacturer figures it's better to ship *anything* rather than nothing.

So it would seem that now is perhaps not the best time to invest in an expensive bit of electronic gear because you don't know whether they've used the best components for the job or whether they've just used whatever they can get their hands on.

Given how many cars are now entirely dependent on microcontrollers and sophisticated electronic subsystems, I wonder if 2021 will be known as "the year of lemons", as auto-makers scramble to undertake quick redesigns of such components in order to substitute parts -- only to have big problems a few years down the track?

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