Crash Sensors

The ADXL251 is a dual-axis, integrated satellite sensor with user selectable g ranges, compliant to the PSI5 Version 2.1 airbag substandard, and backwards compliant to PSI5 Version 1.3. The ADXL251 (x-axis/y-axis) enables low cost solutions for front impact and side impact airbags, as well as satellite sensor and electronic control unit (ECU) main sensor applications. Acceleration data is sent to the control module via a digital, 2-wire current loop PSI5 bus. Communication via the SPI bus is also available for ECU applications.

The device uses an ECC protected one time programmable (OTP) memory. The sensor g range is configurable to provide full-scale measurement of ±60 g, ±120 g, ±240 g, or ±480 g acceleration. The user can program each axis independently with multiple g ranges in different time slots. In PSI5 mode, there are four programmable time slots available. The device transmits 16-bit or 10-bit acceleration data to the control module, and can be configured to include either a 1-bit parity check, or a 3-bit cyclic redundancy check (CRC).

The ADXL251 is available in a 4 mm × 4 mm LFCSP package and is specified to operate over the full automotive temperature range, −40°C to +125°C.

Applications

• Front impact crash sensing
• Side impact crash sensing

The ADXL151 is a g range configurable single axis integrated satellite sensor, compliant to the PSI5 V2.1 specification. The ADXL151 enables low cost solutions for front and side impact airbag satellite sensor applications. Acceleration data is sent to the control module via a digital 2-wire current loop interface bus.

The g range of the sensor is configurable to provide full-scale acceleration measurements of ±120 g, ±240 g, or ±480 g. Additionally, the device can be configured to transmit data from multiple g ranges during predefined time slots, in accordance with the PSI5 specification. The device transmits 10- or 16-bit acceleration data to the control module, and can be configured to include either a 1-bit parity check, or a 3-bit cyclic redundancy check (CRC). The ADXL151 has a unique electronic serial number.

The ADXL151 is available in a 12-lead, 4 mm × 4 mm LFCSP package. The device is specified to operate over the full automotive temperature range, from -40°C to +125°C.

APPLICATIONS

• Front impact crash sensing
• Side impact crash sensing

The ADXRS910 is a high performance in-plane gyroscope, designed for automotive rollover detection applications. The ADXRS910 also has an internal temperature sensor that is used to compensate offset and sensitivity performance, providing excellent stability over the −40°C to +105°C temperature range.

The gyroscope provides a full-scale range of ±300°/sec with a sensitivity of 80 LSB/°/sec. Its resonating disk sensor structure enables angular rate measurement around an in-plane axis. The −3 dB filter corner frequency can be selected to be 27.6 Hz, 51.3 Hz, 109 Hz, or 196.8 Hz. The sensor data output from the device is a 16-bit, twos complement word contained in a 32-bit SPI transaction. SPI communications are compatible up to 10 MHz.

The ADXRS910 is available in a 16-lead inverted SOIC package. The ADXRS910 is specified to operate at 3.3 V and 5 V, with less than 20 mA of current consumption. Its specifications are valid over the −40°C to +105°C temperature range.

Applications

• Rollover detection

The ADXL288 is a dual-axis accelerometer with signal-conditioned outputs available via a 16-bit SPI interface. Identical, independent X and Y sense structures are implemented to create a high performance, high integrity acceleration sensing system.

The X and Y acceleration channels have a nominal full-scale range of ±120 g and a bandwidth of 408 Hz. The acceleration data is provided as a 12-bit, twos complement word with a resolution of 62.5 mg/LSB.

The ADXL288 is available in a 16-lead, narrow-body SOIC package with an exposed pad. The ADXL288 can operate at 3.3 V and 5 V and is specified for operation from −40°C to +105°C.

APPLICATIONS

• Impact sensing
• Shock detection

The ADXL701 device is a high precision, single z-axis accelerometer designed for vehicle rollover detection and other high performance applications. The ADXL701 provides offset stability to better than ±500 mg and sensitivity stability to better than 5% across the entire temperature range. The ADXL701 is designed with selectable −3 dB filter corner frequencies to satisfy a range of applications, and the 2 kHz output data rate allows sufficient oversampling of the acceleration information.

The acceleration data output from the device is a true 16-bit word and is contained in a 32-bit SPI transaction. The SPI interface contains additional fault detection bits and data formatting bits designed to assist high reliability applications. SPI communications are compatible up to 8 MHz. The 16-bit acceleration data-word offers a resolution of 0.434 mg/LSB for the ±14.2 g full-scale range of the device.

The ADXL701 is available in an SOIC package with an inverted paddle for improved EMI/RFI robustness. The ADXL701 operates at nominal power supplies of 3.3 V and 5 V, and is specified to operate across the full automotive temperature range of −40°C to +105°C.

APPLICATIONS

• Vehicle rollover detection
• Platform stabilization/leveling