AIR BAG IGNITION CIRCUIT OF VEHICLE USING SERIAL PARALLEL INTERFACE

PURPOSE: An air bag ignition circuit of a vehicle using serial parallel interface is provided to easily design the ignition circuit, and to easily perform extension by reducing the number of control pins. CONSTITUTION: An air bag ignition circuit of a vehicle using serial parallel interface includes a squib ignition part(10) unfolding an air bag by making ignition current flow through a squib when a high side switch and a low side switch are simultaneously turn on, a leakage sensing part(20) diagnosing short to battery voltage and grounding occasionally generated in a squib part and transmitting the corresponding code to a fault register within a SPI(Serial Parallel Interface) block when a fault is generated, a squib resistance measuring part(30) performing function of self diagnosing whether a squib resistance value is normal by measuring the squib resistance value, and a SPI part(40) converting a serial command from a micro computer into a parallel logic to perform the function of each end and transmitting information as a serial code to the micro computer.