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Freescale delivers energy-efficient 3-axis accelerometer

freescalemma8450qAustin, Tex. — Designed to enhance mobile consumer experiences with improved motion detection, Freescale Semiconductor has introduced the MMA8450Q 3-axis (+/-2g, +/-4g, +/-8g ) accelerometer. Touted as a highly accurate, power-efficient solution that extends battery life for smart mobile devices and captures precise movement via highly sensitive gesture and orientation detection capabilities, the MMA8450Q also survives shocks up to 10,000 g.

The MMA8450Q accelerometer is designed for next-generation mobile devices, such as smartphones and smartbooks, which require a combination of performance, portability and battery life to satisfy market requirements, says Freescale. The 3-axis digital sensor plays a key role in Freescale’s smartbook tablet reference design, which debuted at CES 2010.

The accelerometer offers a broad range of embedded and highly configurable functions designed to help OEMs address specific product requirements, including orientation, tap, double tap, jolt, freefall and shake detection capabilities. The device offers four channels of motion detection: 2 channels for freefall or motion detection, 1 channel for pulse detection and 1 channel for transient detection. It also provides orientation (portrait/landscape) detection with hysteresis compensation

The MMA8450Q sensor, housed in a 3 x 3 x 1-mm package, features 12-bit digital resolution, configurable power saving modes, and auto-wake/sleep capability. It offers intelligent data management capabilities, with an internal first-in/first-out (FIFO) 32-samples/axis (X-, Y- and Z-axis) memory buffer designed to improve overall system power savings and response time by offloading functions from the host processor.

Using the FIFO buffer along with the embedded functions allows the end processor to analyze only the required data, while at the same time helping to protect from potential data loss when multiplexing other sensors on the same I2C bus, says Freescale.

Other features include:

  • Off mode: 2 micro amps
  • Standby mode: 10 micro amps max standby current (I²C active)
  • Active mode (27 to 120 low power mode; 42 to 250 normal mode):
  • 27 micro amps typical (ODR=50 Hz, low power mode)
  • 42 micro amps typical (ODR=100 Hz, low power mode)
  • Programmable 2 interrupt pins for 8 interrupt sources
  • Low voltage operation: 1.71 V to 1.89 V

Target applications include portable consumer devices such as mobile phones and remote controls, as well as smartbooks, eReaders, netbooks, laptop PCs, PMPs and PDAs. Other applications include activity monitoring for medical applications, dead-reckoning assistance for navigation applications, position detection for fleet tracking and safety shutoff for power tools and small appliances.

Availability: Two development kits are available with a PC graphical user interface software program. The RD3924MMA8450Q development kit contains the necessary components for evaluating the MMA8450Q accelerometer including the sensor board (LFSTBEB8450Q) and the USB communication board (LFSTBUSB). They are part of Freescale’s Sensor Toolbox.
Pricing: Starts at $1.67 in quantities of 10,000. For customers who may not have purchased the Sensor Toolbox accelerometer USB board, the RD3924MMA8450 bundles the accelerometer and USB boards for a suggested resale price of $99.

Resources: Low-g accelerometers.