MC33797BPEWR2

Document Number: MC33797 Freescale Semiconductor Rev 6.0, 2/2014 Technical Data Four Channel Squib Driver IC 33797 The Four Channel Squib Driver IC is 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. The device contains a serial peripheral interface (SPI) compatible 8-bit interface to allow microprocessor SQUIB DRIVER 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 the high and low side output drivers are protected against temporary shorts to battery or ground. The current limit threshold is set by an external resistor. This device is powered by SMARTMOS technology. Features Four channel high side and low side 2.0 A FET switches Externally adjustable FET current limiting Adjustable current limit range: 0.8 to 2.0 A EW SUFFIX (PB-FREE) Individual channel current limit detection with timing duration 98ARH99137A measurement, communicated via the SPI 32-PIN SOICW 8-Bit SPI for diagnostics and FET switch activation Diagnostics for high side safing sensor status Resistance and voltage diagnostics for squibs Applications Squib driver IC capability to be used for cross-coupled driver firing Automotive air bag deployment application (allows high and low side FET switches to be located Automatic seat belt retention on separate squib driver ICs) Computer controlled model rocketry igniters Remote firing of pyrotechnic and firework displays Computer controlled firing of blasting caps for mining and construction Military or police weapon systems 33797 V PWR VIN VDIA SQB HI VBOS1 Squib Typical (1A, B 2A, 2B) VFIRE 1 Air Bag FIRING VFIRE 1B Power Supply SENSE CAP VBOOST2 VDIAG 2 SQB LO VFIRE RTN VFIRE 2A FIRING VFIRE 2B 5.0 V CAP R LIMIT 1 VDD R LIMIT 2 CS CLK MISO R DIAG MOSI RST Microprocessor FEN1 ENABLE GND ENABLE FEN 2 Figure 1. 33797 Simplified Application Diagram Freescale Semiconductor, Inc., 2006 - 2014. All rights reserved.1 Orderable Parts Table 1. Orderable Part Variations Temperature (T ) Part Number Package A MC33797BPEW -40 to 85 C 32 SOICW Notes 1. To order parts in Tape & Reel, add the R2 suffix to the part number. 33797 Analog Integrated Circuit Device Data 2 Freescale Semiconductor