Patent ID: 7890232

Claim:
An airbag system comprising a first processing circuit for determining on a collision of a vehicle based on an output from a sensor for detecting a collision of the vehicle and a second processing circuit for outputting a signal to deploy an airbag based on an output from the first processing circuit, wherein the second processing circuit is made of one Application Specific Integrated Circuit, the second processing circuit comprising: a communication unit that controls information communication between the first processing circuit and an electronic control unit outside the airbag system; a first power supply unit that generates a first driving voltage for driving the first and second processing circuits based on a voltage of an outside power supply, the first power supply unit that includes backup power supply unit that supplies a backup voltage when the voltage of the outside power supply falls; a second power supply unit that supplies a second driving voltage to the communication unit based on an output of the first power supply unit; and a power supply control unit that stops the supply of the second driving voltage from the second power supply unit to the communication unit on detection of a fall in the voltage of the outside power supply.