Airbag control unit

An airbag control unit comprising:

• at least one first switch and at least one second switch coupled in series with at least one trigger output between a power source and a ground;
• a first trigger control path coupled to the power source and operable to supply a first trigger signal to the at least one first switch in response to sensing a crash-level shock, wherein the at least one first switch is operable to allow current flow therethrough in response to the first trigger signal, wherein the first trigger control path comprises a first acceleration sensor coupled to the power source, a first filter coupled to the first acceleration sensor, and a first signal conditioner coupled to the first filter, wherein the first trigger control path further comprises a first nonvolatile memory for storing a first armed status and a first logic gate coupled to the first signal conditioner and the first nonvolatile memory, and wherein the first logic gate is operable to supply the first trigger signal only in response to receiving a first conditioned signal while the first armed status is enabled;
• and
• a second trigger control path coupled to the power source and operable to supply a second trigger signal to the at least one second switch in response to sensing the crash-level shock, wherein the at least one second switch is operable to allow current flow therethrough in response to the second trigger signal, wherein the second trigger control path comprises a second acceleration sensor coupled to the power source, a second filter coupled to the second acceleration sensor, and a second signal conditioner coupled to the second filter, wherein the second trigger control path further comprises a second nonvolatile memory for storing a second armed status and a second logic gate coupled to the second signal conditioner and the second nonvolatile memory, and wherein the second logic gate is operable to supply the second trigger signal only in response to receiving a second conditioned signal while the second armed status is enabled.

A method of triggering an airbag inflator comprising:

• providing a first trigger signal in response to sensing a crash-level shock by a first trigger control path, wherein providing the first trigger signal includes:
• generating a first shock signal in response to sensing the crash-level shock by a first acceleration sensor;
• filtering the first shock signal to generate a first filtered signal;
• conditioning the first filtered signal to generate a first conditioned signal;
• and
• reading a first armed status from a first nonvolatile memory, wherein
• providing the first trigger signal only occurs when the first armed status is enabled;
• providing a second trigger signal in response to sensing the crash-level shock by a second trigger control path, wherein providing the second trigger signal includes:
• generating a second shock signal in response to sensing the crash-level shock by a second acceleration sensor;
• filtering the second shock signal to generate a second filtered signal;
• conditioning the second filtered signal to generate a second conditioned signal;
• and
• reading a second armed status from a second nonvolatile memory, wherein providing the second trigger signal only occurs when the second armed status is enabled;
• and
• outputting a voltage to a trigger output in response to providing the first trigger signal and providing the second trigger signal, wherein outputting the voltage further includes closing at least one first switch in response to providing the first trigger signal and closing at least one second switch in response to providing the second trigger signal.

An airbag control unit comprising:

• a first acceleration sensor coupled to a first filter which is coupled to a first signal conditioner;
• a first AND logic gate coupled to the first signal conditioner and a first nonvolatile memory;
• a second acceleration sensor coupled to a second filter which is coupled to a second signal conditioner;
• a second AND logic gate coupled to the second signal conditioner and the first nonvolatile memory or a second nonvolatile memory;
• a power source coupled to the first acceleration sensor, the second acceleration sensor, and at least one trigger output;
• at least one first switch coupled to the first AND logic gate and the at least one trigger output;
• and
• at least one second switch coupled to the at least one first switch, the second AND logic gate, and a ground.