Since the airbag was introduced its reliability and safeness has been improved continuously. A very important role comes up to the microcontroller that determines when to fire the airbag(s) based on sensor data.
COMPONENTS
Infineon''s 16-bit microcontroller C164CL/CG suits this application perfectly in combination with a micromachined acceleration sensor. The sensor provides measurement in two dimensions and including sensing, signal conditioning, system interface, and self-test capability.
Highly integrated power devices that reduce board space and pin count are dedicated to airbag applications. Application Specific ICs (ASICs) to fire and test the squibs are good examples. A power supply with step-down and step-up converters is fully integrated, too. This integration is possible due to Infineon''s smart power technologies combining bipolar, CMOS, and DMOS, on one chip. Infineon has already shipped more than 53 million System IC devices for airbag applications.
SCHEMATIC DIAGRAM of an airbag Electronic Control Unit (ECU):
