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When designing the layout of an electronic circuit for a smartphone, are there any ways in which the electronics can be designed to be able to withstand larger accelerations/shocks.

To aid the above design, I am also trying to determine the maximum acceleration the electronics within a typical smartphone can withstand.

I have found this [IEEE Paper][1]

It seems to say that cell phones can withstand up to 2000 G for several milliseconds before experiencing damage to their solder connections. However this is an old paper, and thus very different to today's smartphones.

[1]: https://ieeexplore.ieee.org/document/1644050)

Voltage Spike
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dgldy
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  • Design to resist mechanical shock seems to be an electronic design issue from here. I suppose you can call it a packaging issue, but if there's PCB-level technique to resist high-g impulse, I'd love to hear about it. – Scott Seidman Sep 09 '13 at 17:44

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I'd advise having a mooch round NASA's various engineering publications, they have some good stuff. The laws of physics and strength of solder haven't really changed much so old material can still be relevant. It should be obvious that modern boards using tiny (light) SMT components will suffer less from shock loading than big dumb stuff with big heavy components, but some parts (thinner PCB's, thinner screens) will be more "brittle" (not the correct term but close).

2000G for a few milliseconds is marketing speak for "being dropped onto a hard floor", it doesn't take much to make big G numbers in a short transient (impact), it doesn't equate to anything like being able to strap it to a cruise missile and still function (fun experiment though!).

Some laptop hard drives are rated up to a seemingly impressive 100G or so while running, more when parked, what that means in real life may be slightly less impressive - and ruggedised laptops cradle them in a foam/gel carrier to cushion the bumps. If you look at the case design of a lot of gear (esp. phones, MP3 players, and TV remotes, which get dropped a lot) there's some very cunning impact protection built into the case.

Even the tiniest bit of cushioning will knock the tip of the transient off and reduce the G number by a huge amount - much like the crumple zones in cars. Converting a sharp spike of force into even a slightly rounded bump gives everything else a much easier time.

NASA's workmanship reference: http://workmanship.nasa.gov/lib/insp/2%20books/frameset.html

John U
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