Inexpensive hi-res MEMS pressure sensor opens door to advanced location services for mobiles

Inexpensive hi-res MEMS pressure sensor opens door to advanced location services for mobiles

Working with accelerometers and magnetometers, the Xtrinsic MPL3115A2 MEMS-based pressure sensor is designed to help developers leverage advanced navigation capabilities and emerging location-based services such as GPS assist and e911, augmenting planar map location with precise altitude information.

The device provides barometric / altimetry pressure detection over a range of 20 to 110 kPa with resolution as fine as 30 cm, and delivers a digital output in either pascals or meters according to the user’s preference. The sensor also includes embedded functions and user-programmable options, such as temperature compensation, with variable sampling rates to 128 Hz.

The smart sensor can locally processes the pressure and temperature data it collects and digitizes, offloading the host system’s applications processor and thus reducing power significantly when compared to systems that only use basic sensors. Smart features include autonomous data acquisition with two interruptions on thresholds detection.

To enhance efficiency, the device regulates auto-wake and sleep modes (to avoid unnecessary use of power) and requires zero data processing for mobile devices and medical and security applications. The sensor further optimizes operating efficiency with a FIFO memory buffer to decrease the need for frequent communication. And current draw is a mere 2 μA in standby mode and 8.5 μA in low-power mode. ($1.50 ea / 10,000 — sample quantities available now, prod qty 3rd qtr; KITSTBMPL3115A2 development board, $75; DEMOSTBMPL3115A2, with development board and a USB board, $99 — available 3rd qtr.)

By Richard Comerford

Freescale Semiconductor , Austin , TX
Information 800-521-6274
www.freescale.com