AIS326DQTR STMicroelectronics

AIS326DQ MEMS inertial sensor 3-axis, low g accelerometer with digital output Features 3.3 V single supply operation 1.8 V compatible IOs SPI digital output interface 12 bit resolution Interrupt activated by motion Programmable interrupt threshold QFPN-28 Embedded self-test High shock survivability ECOPACK compliant process developed by ST to produce inertial sensors and actuators in silicon. Extended temperature range -40 C to +105 C The IC interface instead is manufactured using a CMOS process that allows high level of Applications integration to design a dedicated circuit which is Anti-theft systems and inertial navigation factory trimmed to better match the sensing element characteristics. Motion activated functions Vibration monitoring and compensation The AIS326DQ has a user selectable full scale of 2 g, 6 g and it is capable of measuring Tilt measurements acceleration over a bandwidth of 640 Hz for all Black boxes, event recorders axes. The device bandwidth may be selected accordingly to the application requirements. The Description self-test capability allows the user to check the functioning of the system. The AIS326DQ is a three axes digital output The device is available in plastic quad flat accelerometer that includes a sensing element package no lead surface mount (QFPN) and it is and an IC interface able to take the information specified over a temperature range extending from the sensing element and to provide the from -40 C to +105 C. measured acceleration signals to the external world through an SPI serial interface. I C compatible interface is also available. The sensing element, capable of detecting the acceleration, is manufactured using a dedicated Table 1. Device summary Operating temperature Order code Package Packing range C AIS326DQ -40 to +105 QFPN-28 Tray AIS326DQTR -40 to +105 QFPN-28 Tape and reel June 2010 Doc ID 14956 Rev 4 1/51 www.st.com 51Contents AIS326DQ Contents 1 Block diagram and pin description . 8 1.1 Block diagram . 8 1.2 QFPN-28 pin description 8 2 Mechanical and electrical specifications . 10 2.1 Mechanical characteristics 10 2.2 Electrical characteristics 12 2.3 Communication interface characteristics . 13 2.3.1 SPI - serial peripheral interface . 13 2.4 Absolute maximum ratings 14 2.5 Terminology . 15 2.5.1 Sensitivity 15 2.5.2 Zero-g level 15 2.5.3 Self test . 15 3 Functionality 16 3.1 Sensing element 16 3.2 IC interface 16 3.3 Factory calibration 17 4 Application hints . 18 5 Digital interface 19 5.1 SPI bus interface . 19 5.1.1 SPI Read 20 5.1.2 SPI Write 21 5.1.3 SPI Read in 3-wires mode . 22 6 Register mapping 23 7 Register description 25 7.1 WHO AM I (0Fh) . 25 7.2 OFFSET X (16h) . 25 2/51 Doc ID 14956 Rev 4