FEATURES

► 0 g offset vs. temperature (all axes): 0.75 mg/°C maximum

► Ultralow noise spectral density (all axes): 75 µg/√Hz

► Low power, VSUPPLY (LDO regulator enabled)

► ADXL356 in measurement mode: 150 µA

► ADXL357/ADXL357B in measurement mode: 200 µA

► ADXL356/ADXL357/ADXL357B in standby mode: 21 µA

► ADXL356 has user adjustable analog output bandwidth

► ADXL357/ADXL357B digital output features

► Digital SPI and limited I2C interfaces supported

► 20-bit ADC

► Data interpolation routine for synchronous sampling

► Programmable high- and low-pass digital filters

► Integrated temperature sensor

► Voltage range options

► VSUPPLY with internal regulators: 2.25 V to 3.6 V

► V1P8ANA, V1P8DIG with internal LDO regulator bypassed: 1.8 V typical ± 10%

► Operating temperature range: −40°C to +125°C

► 14-terminal, 6 mm × 5.6 mm × 2.2 mm, LCC package

APPLICATIONS

► Inertial measurement units (IMUs)/attitude and heading refer ence systems (AHRSs)

► Platform stabilization systems

► Structural health monitoring

► Seismic imaging

► Tilt sensing

► Robotics

► Condition monitoring

GENERAL DESCRIPTION

The analog output ADXL356 and the digital outputs ADXL357 and ADXL357B are low noise density, low 0 g offset drift, low power, 3-axis accelerometers with selectable measurement ranges. The ADXL356B supports the ±10 g and ±20 g ranges, the ADXL356C supports the ±10 g and ±40 g ranges, and the ADXL357 and ADXL357B support the ±10 g, ±20 g, and ±40 g ranges.

The ADXL356/ADXL357/ADXL357B1 offer industry leading noise, minimal offset drift over temperature, and long-term stability, ena bling precision applications with minimal calibration.

The low drift, low noise, and low power ADXL357 and ADXL357B enable accurate tilt measurement. The ADXL357B is more ro bust/suitable for tilt sensing in high vibration environments. The low noise of the ADXL356 over higher frequencies is ideal for con dition-based monitoring and other vibration sensing applications.

The ADXL357 and ADXL357B multifunction pin names may be referenced only by their relevant function for either the serial periph eral interface (SPI) or limited I2C interface.

SPECIFICATIONS

1 The resonant frequency is a sensor characteristic.

2 Characterized but not 100% tested.

3 Repeatability is predicted for a 10 year life and includes shifts due to the HTOL (TA = 150°C, VSUPPLY = 3.6 V, and 1000 hours), temperature cycling (−55°C to +125°C and 1000 cycles), velocity random walk, broadband noise, and temperature hysteresis. Repeatability in relation to time follows the square root law. For example, to obtain offset repeatability of the x-axis for 2.5 years, use the following equation: ±4.25 mg × √(2.5 years/10 years) = ±2.125 mg.

4 The temperature change is −40°C to +25°C or +25°C to +125°C.

5 The VRE measurement is the shift in dc offset while the device is subject to 12.5 g rms random vibration from 50 Hz to 2 kHz. The DUT is configured for the ±40 g range and an output data rate of 4 kHz. The VRE scales with the range setting.

6 Based on characterization.

7 ±40 g indicates a test condition. The self test result converted to the acceleration value is independent of the selected range.

8 When V1P8ANA and V1P8DIG are generated internally, VSUPPLY is valid. To disable the LDO regulator and drive V1P8ANA and V1P8DIG externally, connect VSUPPLY to VSS.

9 Standby to measurement mode. This specification is valid when the output is within 1 mg of final value.