ADXL103 data sheet confusion

[Mikebits]

With all the talk about accelerometers lately, I decided to read up on these elusive little parts. Heck with 8 pins, how complicated can they be?

Well, I am confronted with a bit of (no scratch the bit as the output is analog) confusion.

In the ADXL data sheet https://www.electro-tech-online.com/custompdfs/2008/08/ADXL103_203-1.pdf

I get that a squarewave is generated in relation to G and tilt, so the output must be filtered so that a sinusoid waveform is made. What I am not clear about, is this output constant or more like an impulse response.

In an appnote I found, it was shown that the part could be used as a tilt detector. Is that to say that as long as the part is in a tilted angle a proportional output sine will be produced?

I also could not seem to figure out how to come up with any interface as I do not know how one converts millivolts/G to tilt. If I tilt the part say x deg, how do I know sine amplitude out.

Sorry, this data sheet eludes me. Thanks for any insight...

 

[Roff]

Mike, you are not looking for a sinusoid on the output. With constant acceleration, the output is a DC voltage. The capacitor sets the bandwidth of the response to change in acceleration. If you had a step in acceleration, the output voltage would be a step. The cap will set the risetime of that step. The purpose is to filter out unwanted acceleration "noise", to eliminate aliasing due to downstream A/D sampling rate, and maybe to filter out residual higher frequency crap which remains on the internal demodulator output.
Disclaimer: I haven't used this part. I just read the datasheet, plus I am an old retired EE with lots of experience.

 

[Mikebits]

Thanks Ron, I kinda thought that may be the case but was just not sure.