Does the ADXL335 Accelerometer measure static acceleration of gravity?

On the 1st page of the data sheet for the ADXL335, under 'General Description' it states that it does measure static gravity. However, it then states that the low frequency cutoff is 0.5 Hz. It is to my understanding that the low frequency cutoff needs to be 0 Hz to measure static gravity. So does this product for sure measure static acceleration of gravity? 

ADXL335.pdf
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    •  Analog Employees 
    on Nov 14, 2016 9:49 PM

    Thank you for your post! The original author of this datasheet does not support this product anymore so can you save us the time of digging through the entire datasheet and point out the specific point of reference that is concerning you?  I suspect that you could be referring to one of the filtering examples, which might actually be a low-pass response, but having the specific point of reference would be helpful. Thank you!

  • Hi thanks for the response. So I want a accelerometer that can measure static acceleration of gravity. Right under the 'General Description' on page 1 of the datasheet it states "(The ADXL335) can measure the static acceleration of gravity in tilt-sensing applications, as well as dynamic acceleration resulting from motion, shock, or vibration". After reading that I was confident this device would work. However in the very next paragraph it states, "The user selects the bandwidth of the accelerometer using the CX, CY, and CZ capacitors at the XOUT, YOUT, and ZOUT pins. Bandwidths can be selected to suit the application, with a range of 0.5 Hz to 1600 Hz for the X and Y axes, and a range of 0.5 Hz to 550 Hz for the Z axis". This paragraph confused me. I thought in order to measure static acceleration of gravity that the bandwidth low range had to be 0 Hz, because doesn't 0.5 Hz need a small amount of dynamic acceleration? I am a college student so I was just hoping for some clarification on this accelerometer, to be sure it is the one I want. It doesn't really talk about the bandwidth and static acceleration elsewhere in the data sheet. Hope that helps you more.

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    •  Analog Employees 
    on Nov 14, 2016 10:25 PM

    Thank you! I am very sure that this does not refer to the start frequency of a band-pass filter. Just speculating, but I suspect that this could be describing the corner of the 1/f responses, which is when the relationship between the total noise and bandwidth changes. Hope that helps!