Airbag energy storage voltage

Why do airbags have energy reserve capacitors?

The energy reserve capacitors used in the ACU (Airbag Control Unit) are provided so that once a crash event occurs and Loss of Battery (LOB) occurs in turn, the airbags can still be powered with their help as an emergency supply system.

What is a typical airbag application circuit?

Fig 1 shows a typical airbag application circuit. The supply voltage is usually 25 V to 35 V, which is provided by a boost converter operating from the 12 V car battery. The squib firing voltage is usually 15 to 20 V, which is controlled by the IC controller, this means the MOSFET drain to source voltage V DS is 10 V to 15 V.

What is an air bag energy reserve?

The energy reserve is a power backup for the air bag system. When a vehicle accident happens and the battery supply is lost, the energy reserve can provide sufficient power to support the system to continuously collect sensor information, process safing messages, and fire squibs, for a time determined by the capacity of the energy reserve.

How do airbag modules work?

Airbag modules are continuing to evolve and proliferate. Most of these devices are similar in that they take an electrical signal from the vehicles crash sensing system, activate, or ignite, an inflator to rapidly produce an inert gas, use that gas to fill a cushion, which then provides energy absorption to the vehicle occupant(s).

What is a typical airbag squib application circuit?

Airbag Squib typical application circuit Fig 1 shows a typical airbag application circuit. The supply voltage is usually 25 V to 35 V, which is provided by a boost converter operating from the 12 V car battery.

How do airbags work?

Determine the ignition timing for airbags Supply power circuits with energy via ignition capacitor (independent of the vehicle battery) The airbag module processes all important signals sent by the sensors and uses this information to determine the activation strategy of the airbags.