STMicroelectronics introduces robust, low-power automotive accelerometers

     The AIS2DW12 automotive accelerometer from ST makes the car's Passive Keyless Entry (PKE) system key card robust and safe from the inevitable drops and scratches that occur during the key's life cycle. The accelerometer also features ultra-low power consumption, adding a utility to the PKE key card on the basis of portability and excellent motion-sensing anti-theft function.

     The ordinary PKE key card can continuously listen to the vehicle, wait for the "unlock" request launched when pulling the door handle, and then send the vehicle unlock command. Thieves can use the intermediate transmitter to forward the unlock request, force the key card that is beyond the communication distance (placed on the dining table in the owner's home) to send the unlock command, obtain the permission to open the door, and steal the vehicle.

     With the accelerometer, when there is no movement and it is out of communication range, the key card can shut down the RF receiver and ignore the malicious relay transmission. Only when the owner approaches the vehicle and detects movement at close range will the key card wake up the receiver. In addition, turning off the receiver during idle periods also helps to extend battery life.

     Unlike some other accelerometers targeted at PKE, ST's AIS2DW12 has passed rigorous automotive industry crash tests. As a result, car owners can enjoy increased security without the extra hassle of protecting vulnerable key cards, and longer battery life is an added benefit.

     The use of a dedicated internal engine for motion and direction detection, excellent energy efficiency, at 1.6Hz, the working current is only 380nA, less than half of the competition, further saving battery power. The AIS2DW12 uses a 1.8V DC power supply, can be powered by a lithium battery, digital output, full scale up to 4g.

     AIS2DW12 is AEC-Q100 certified to the Automotive Production Parts Approval Process (PPAP) Level 3 standard and is available in a 2mm x 2mm x 1mm 12-contact grid array (LGA) package.