TEMIC is a subsidiary of Daimler-Benz, known for its application-specific products in the areas of semiconductors, microsystems, automotive electronics, and airbag inflators. TEMIC's Microsystems business unit in Nuremberg, Germany, recently decided to introduce DuPont's 2000 Series resistor system into its production process.

The first use of the resistor system is for an advanced Continuously Variable Transmission (CVT) controller, which regulates the continuously variable drive of a car and accommodates pressure, temperature, speed control and position sensors. The circuitry was designed to operate reliably at a temperature range between -40°C and +150°C.

Challenge: High Performance and Design Latitude in a Complex Automotive Controller

The new DuPont resistor series was introduced because available thick film resistor technology could not meet the high performance requirements of the complex CVT circuit. TEMIC also sought improved TCR tracking, durability and stability.

Solution: DuPont Resistors Provide Design, Performance Benefits

The DuPont 2000 Series resistor system has minimum length and termination effect, allowing TEMIC to design resistors with a length and width as small as 0.5 mm, while improving absolute TCR from 100 ppm/°K down to 60 ppm/°K. TCR tracking performance was 40 ppm/°K in different versions of the Series. The power handling of the resistors was almost twice as high as that of previous versions, allowing for a reduction in resistor size.

Additional benefits provided by the 2000 Series resistors are low noise characteristics (rated up to five times better than those of conventional systems), improved post-laser trim stability (improved by a factor of three), and outstanding durability at high temperatures. The 20 µm dry print thickness of the 2000 Series results in reduced material consumption and faster trimming in the production process. The high performance of the resistors also offers wider design latitude and improved flexibility for advanced circuit development, so that TEMIC can better meet the needs of its customers, and pass on cost and performance benefits.

DuPont's 6119 Ag-Pd conductor and 9770 high-Ag-containing Ag-Pt conductor were also specified for the TEMIC CVT circuit. There were no significant changes in sheet resistivity, even when different termination materials were used.

For more information, call DuPont at 1-800-284-3382, press 3.