Microscopic analysis of common semiconductors, ICs and more

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As a technician back in the 60s working for MIT Instrumentation lab on a very early DC to DC switching PS, I would routinely grind the top off TO-3 power transistor cases to investigate for failure mode. It was fairly easy to see fused open circuit base leads from too much base current (typically >1A) , or over voltage breakdowns in collector region. These become visible from the local melting that occurs after the short circuit at the punch through site between collector-emitter region causes extreme localized heating from the resulting high current flow.

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Later in the early 70s at my next job (working on variable speech control) we were licensing our patented technology to Panasonic. We used Interdesign monochips to put the entire pitch shift control circuitry into three of their semi-custom ICs. Panasonic performed an embarrassingly detailed technical review of the monochips from a prototype we supplied, with micro-photographs pointing out marginal clearances and the like inside the monochips. I expect the big established Japanese company didn't appreciate working with a tiny US start-up, so wanted to one-up us.

I spent some time with the junior(?) Japanese engineer sent over here to work with us while we taught them how to set up the system trims. I recall once while taking him out to lunch, his amazement that I was allowed to still drive my car with a cracked windshield. In Japan that would not be allowed until the windshield was replaced.

JR   
 
This groks with my (limited) experience with synths, outboard and cars. The attention to detail, the amount of pre-planning, commitment to quality, longevity and robustness even for relatively cheap goods made in Japan is second to none IMO.

German-made is closest, but tends to be more over-engineered and less efficient.

Made in the UK gear tends to be on the other side and US equipment is similar. Lot's of revisions, quirks and ideosyncracies, and relatively high failure rate. Design-decisions that appear to be strange and erratic and often not the technically correct way to do it. But that's where a lot of magic has happend. I will pay a lot of money next month to have my AMS delay fixed. :)
 
living sounds said:
This groks with my (limited) experience with synths, outboard and cars. The attention to detail, the amount of pre-planning, commitment to quality, longevity and robustness even for relatively cheap goods made in Japan is second to none IMO.
Not to quibble about stereotypes but I am old enough to remember when Made in Japan, stood for cheap inferior goods. 

In the 1950s a quality movement by Dr Edwards Deeming, instilled a new culture of quality there. Perhaps search the Japanese Deeming Prize. BTW Deeming was an American. 8) 
German-made is closest, but tends to be more over-engineered and less efficient.
German auto engineering has recently become synonymous with cheating emissions standards, but that is only one (several related companies) high profile events.
Made in the UK gear tends to be on the other side and US equipment is similar. Lot's of revisions, quirks and ideosyncracies, and relatively high failure rate. Design-decisions that appear to be strange and erratic and often not the technically correct way to do it. But that's where a lot of magic has happend. I will pay a lot of money next month to have my AMS delay fixed. :)

I have seen examples of good and bad engineering from multiple countries.

Here's another anecdote about German engineering. Back at Peavey when I was responsible for powered mixers I had to deal with our german reps complaining about a domestic German powered mixer brand that was very competitive in their market. I had to bring one back to my lab for bench testing. What I discovered was a non-flat frequency response when all controls were set flat (to 12 o'clock). Digging deeper, there was no subtle human factors engineering built into the circuitry, but a sloppy use of the wrong knob for the application. The knobs with splined shaft were designed for use on pots with a vertical orientation, but when used on horizontal oriented pots like in that mixer the the result at 12 o'clock was slight boost. Mystery solved.....but the perception bias, made the German reps interpret the non-flat response as somehow better than Peavey.

They may have been drinking the same kool aid. 

JR
 
Yes, the more I thought about it, the less my blanked assessment seemed to be correct.

Most of what I think of as "German gear" is classic no-expense-spared broadcast technology (LAWO and ADT mixing consoles, Telefunken tape machines, Neumann mics etc.). And I agree about the "Dieselgate" problem, of course.



 
Wow that's mind blowing. Thanks for sharing.

How do they do that! The LT1088 is a work of art...

 

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