The NXP® MC33797 is a four-channel squib driver integrated circuit with a complete squib diagnostic and deployment interface for use in automotive air bag modules.
Extensive diagnostics and system control features are incorporated to provide fail-safe operation
Contains a SPI-compatible 8-bit interface to allow microprocessor control
The device has the capability to be used in a standard four-channel squib driver IC or in a cross coupled state with the high- and low-side squib drivers located on separate squib driver ICs
Both high- and low-side output drivers are protected against temporary shorts to battery or ground and the current limit threshold is set by an external resistor
Four-channel high-side and low-side 2.0 A FET switches
Externally adjustable FET current limiting
Adjustable current limit range: 0.8 A to 2.0 A
Individual channel current limit detection with timing duration measurement, communicated via SPI
8-bit SPI for diagnostics and FET switch activation
Diagnostics for high-side safing sensor status
Resistance and voltage diagnostics for squibs
Squib driver IC capability to be used for cross-coupled driver firing application (allows high- and low-side FET switches to be located on separate squib driver ICs)
Four-channel high-side and low-side 2.0 A FET switches
Externally adjustable FET current limiting
Adjustable current limit range: 0.8 A to 2.0 A
Individual channel current limit detection with timing duration measurement, communicated via SPI
8-bit SPI for diagnostics and FET switch activation
Diagnostics for high-side safing sensor status
Resistance and voltage diagnostics for squibs
Squib driver IC capability to be used for cross-coupled driver firing application (allows high- and low-side FET switches to be located on separate squib driver ICs)
