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I'm working on a project on the Samsung Galaxy S smartphone. I need to know some additional information on its accelerometer that I can't find. Accelerometer datasheet

I need to know following details:

  • which type of measurement range they use? +-2g , +-4g or +-8g ?
  • noise depend on the bandpass filter used by the smartphone: how much is the band?
  • there is some way to evaluate from this data sheet the standard deviation of drift process of the sensor?
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All of those details are heavily dependent on the firmware setting up the chip, low level software (Android OS) massaging and delivering the sensor data, and finally the application-level software further massaging and delivering data. At the firmware level, it would be useful to get an SPI/I2C sniffer, like the Bus Pirate or Open Bench Logic Sniffer. I wouldn't be surprised if applications were able to access this level, as well. In other words, the initial or default state may change. It will be very difficult to attach probes, however.

The Android OS is largely open-source. Check it out and see if you can find the relevant blocks of code and libraries. It would at least set the initial state, and likely define an API to change it.

The wrong way to go about this is physical tests while taking measurements with an on-board application. There are at least 3 layers of algorithms fiddling with the sensor data.

You cannot determine drift from the datasheet. It is dependent on temperature, age, and batch/wafer.

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    \$\begingroup\$ Sensor API developer.android.com/reference/android/hardware/Sensor.html \$\endgroup\$ – jsolarski Mar 12 '11 at 17:27
  • \$\begingroup\$ API dosen't allow to change them. I think that i can find this data in the api source, but it is not simple. Now i'll try. \$\endgroup\$ – MarcoBiagi Mar 13 '11 at 10:36
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    \$\begingroup\$ For the drift i need only the standard deviation at costant tempereture. I cannot determine it from the datasheet? \$\endgroup\$ – MarcoBiagi Mar 13 '11 at 10:47
  • \$\begingroup\$ Drift can and should be specified. If you look at the data of chip sensors, drift is specified. If it isn't with the phone specs, then there's something strange. \$\endgroup\$ – jcoppens Jun 22 '15 at 14:07

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