At 01:00 PM 5/28/2004 -0700, you wrote:
>Hi folks...
>    I've not used an accelerometer in a project before, so I wonder if anyone
>can give recommendations.  I think what I'm after is one of the piezo-type
>devices; preferably in a very small surface-mount package.  All I really
>need is a single-axis capability, but I do need to sense bidirectionally on
>that axis.  It needs to be low-voltage (3VDC would be ideal), and have
>excellent low freq response (below 2 Hz).  I don't care much about anything
>above 100Hz.  It also needs to have good immunity to physical shock (e.g.,
>when the moving component carrying the sensor slams into a fixed object); on
>this point, I don't yet know how to characterize that force - I know the
>mass of the moving component, but not (yet) the force being applied to make
>it move.  (p.s. I'm not a physicist, either :^)... just a software guy,
>mostly, so if you have any suggestions around that I'd appreciate hearing!).
>   Thanks for any ideas you might have!
>Jim

I've used Analog Devices' accelerometers with no problems (read the
specs carefully), but they are MEMS parts, not piezo, so they give an
output down to DC, at least some will work from a 3V supply. Some even
have digital output. I suspect the shocks in transportation and
assembly (dropping from 3' on a concrete floor, for example) will exceed
anything the part sees in service unless you are making something along the
lines of artillery rounds. http://www.analog.com ADXLxxx series.

You can also check out Measurement Specialties at http://www.msiusa.com

Best regards,

Spehro Pefhany --"it's the network..."            "The Journey is the reward"
speff@interlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com

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