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[on:]

I want to create a simple seismometer based on MMA7361 accelerometer. I read from many literature about seismic wave frequency and peak ground acceleration (PGA). It is clear that MMA7361 qualified for acceleration measuring range 1.5 g or 6 g (maximum earthquake acceleration recorded in history is about 1,24 g). But, it is not defined (on datasheet) about frequency response of this sensor. Seismic wave frequency range (non exploration) can be smaller than 0.001 Hz and maximum frequency up to 200 Hz.

Is this MMA7361 frequency response qualified for frequency from 0.001 Hz to 200 Hz? Anybody testing frequency response this MMA7361 accelerometer?

[Reply #1 on:]

Did you not see in the datsheet (http://www.sparkfun.com/datasheets/Components/General/MMA7361L.pdf) where is says:

Bandwidth Response
XY  Typically 400 Hz
Z    Typically 300 Hz


Since the sensitivity and zero offset will vary with temperature you might want to have your accelerometer in a temperature-controlled environment.  The operating temperature range goes up to 85°C so a little oven to keep the temperature around 40°C might do the trick.

[Reply #2 on:]

Did you not see in the datsheet (http://www.sparkfun.com/datasheets/Components/General/MMA7361L.pdf) where is says:

Bandwidth Response
XY  Typically 400 Hz
Z    Typically 300 Hz


Since the sensitivity and zero offset will vary with temperature you might want to have your accelerometer in a temperature-controlled environment.  The operating temperature range goes up to 85°C so a little oven to keep the temperature around 40°C might do the trick.

OK, thanks for advice. I will do temperature test first.