Nanopower, 3-Axis, ±2 /±4 /±8 Digital Output MEMS Accelerometer

The ADXL367 is an ultralow power, 3-axis microelectromechanical systems (MEMS) accelerometer that consumes only 0.89 μA at a 100 Hz output data rate and 180 nA when in motion-triggered wake-up mode. Unlike accelerometers that use power duty cycling to achieve low power consumption, the ADXL367 does not alias input signals by undersampling, but samples the full bandwidth of the sensor at all data rates.

The ADXL367 always provides 14-bit output resolution. 8-bit formatted data is offered for more efficient single-byte transfers when a lower resolution is sufficient. 12-bit formatted data is also provided for ADXL362 design compatibility. Notice that the low and high bytes are inverted, compared with the ADXL362 word formatting. Measurement ranges of ±2 g, ±4 g, and ±8 g are available, with a resolution of 0.25 mg/LSB on the ±2 g range.

In addition to its ultralow power consumption, the ADXL367 has many features to enable true system level power reduction. It includes a deep multimode output first in, first out (FIFO), a built-in micropower temperature sensor, an internal analog-to-digital converter (ADC) for synchronous conversion of an additional analog input with interrupt capability, single-tap and double-tap detection that can operate at any output data rate with only an added 35 nA of current, and a state machine to prevent a false triggering. In addition, the ADXL367 has provisions for external control of the sampling time and/or an external clock.

The ADXL367 operates on a wide 1.1 V to 3.6 V supply range, and can interface, if necessary, to a host operating on a separate supply voltage. The ADXL367 is available in a 2.2 mm × 2.3 mm × 0.87 mm package.

APPLICATIONS

* 24/7 sensing

* Hearing aids

* Vital signs monitoring devices

* Motion-enabled power save switches

* Motion-enabled metering devices

* Smart watch with single-cell operation

* Smart home

* Supply voltage range

* Single-cell battery operation: 1.1 V to 3.6 V

* Internal power supply regulation for high PSRR

* Ultralow power

* 0.89 μA at 100 Hz ODR, 2.0 V supply

* 180 nA motion activated wake-up mode

* 40 nA standby current

* High resolution: 0.25 mg/LSB

* Built-in features for system level power savings

* Single-tap and double-tap detection with only 35 nA of added current

* Adjustable threshold sleep and wake-up modes for motion activation

* Autonomous interrupt processing, without need for microcontroller intervention, to allow the rest of the system to be turned off completely