Freescale Semiconductor has introduced an advanced low-power sensor based on MEMS (micro-electromechanical system) technology specifically engineered for handheld portable electronic devices. The three-axis MMA7660FC accelerometer enhances user interfaces for mobile phones, small appliances and gaming by allowing the user to tap, shake or orient the device for specified commands. The device also includes smart power management features to help extend battery life.
Adoption of accelerometers in portable electronics offer advanced user interfaces on mobile devices, such as touch-screen and orientation detection. The new cost-effective accelerometer integrates smart motion features such as orientation, shake and tap detection with auto wake-up/sleep detection in a compact package. The accelerometer can be configured with custom portrait/landscape trip points for six orientations comprising left, right, up, down, back and front. The accelerometer provides precise hand movement control and communicates directly with the main system processor through an I2C interface for communication simplicity and flexibility.
The accelerometer provides long battery life when continuously operating to determine motion. Configurable power saving modes and a power-select capability helps designers to achieve optimal current consumption by choosing one of eight sample rates. System-level power is reduced through an automatic configurable auto wake-up/sleep feature achieved without intervention or polling by the host processor. The accelerometer provides conversion to digital values at a user-configurable output data rate, offering proportional savings in supply current and power.
Key applications for the accelerometer include portable consumer devices such as mobile phones, PDAs and digital cameras. Additional applications include shock detection and motion control in PCs and peripherals, activity monitoring in medical and sports applications, and orientation and freefall detection in gaming and toys.
Other features of the accelerometer include ±1.5g three-axis digital accelerometer with I2C, low-profile 3x3x0.9mm DFN package, configurable output data rate from 1 to 120samples/s and ability to survive shocks up to 10,000g. The current consumption of the accelerometer is 0.4μA in off mode, 2μA in standby mode and 47μA at 1sample/s in active mode.
