Why accelerometers widely used by mobile devices

Accelerometers are very interesting devices. It seems that every cell phone on the planet has these devices built in. They can tell the orientation of the phone and allow the software to change the perspective of the screen in response to the movement of the phone. You can play games on your phone by simply moving the phone to interact with the game. Some of the newer video games are using accelerometers in their controllers to give more realistic play. Other applications that involve detecting motion would benefit from using them. If you need positional information then a GPS is a must. I find them fascinating.

There are several different styles 2 axis, 3 axis, analog output, and digital output. I understand that the dual axis is slowly being replaced by the 3 axis type. The analog output types require an ADC to interact with. The digital types are typically either I2C or SPI. I find that the digital type are more precise and typically can be read more quickly. I guess that is debatable as some of the newer microcontrollers have fairly fast ADC’s with DMA access which should allow very fast sampling of the accelerometer.

I have attached a 3 axis analog accelerometer to an MSP430F2002. I hooked it up to three analog inputs and run the conversions in success as fast as I can run the ADC. I have a large battery so, I don’t have to worry about being extremely low power.