Welwyn Components and AB Mikroelektronik have developed a new technique for producing hybrid circuits. Called Patchwork, the technology integrates power components, current-sense resistive elements, and control circuitry on a single, ceramic substrate. The resulting hybrid modules are claimed to enable automotive-systems engineers to design power-electronic controls capable of operating at temperatures between -50°C and 150°C. Patchwork technology combines conventional thick-film elements on ceramic substrates with the high-current carrying capabilities of thick-film copper conductors. The copper is printed in varying thicknesses from 25 microns for control components up to 200 microns for power conductors and current-sensing elements and the Patchwork technology provides the interface between conventional thick film and the 25-micron copper film.