Molded hybrid IC packages

AT&T´s new system products will incorporate hybrid ICs with significantly more I/O connections than current designs, predominantly in surface-mount package formats. A family of plastic molded packages that conform to JEDEC standards is being developed for these hybrid IC applications. The packages are identical in both appearance and performance to those of discrete ICs, simplifying system design because standard CAD libraries can be utilized, improving manufacturability because industry standard equipment can be used, and improving overall system reliability because circuit boards can be manufactured using standardized components, equipment and processes that are better characterized and controlled. The mechanical reliability of quad packages with 68 and 124 leads on 50-mil pitch and 132 leads on 25-mil pitch has been investigated. The results indicate that all three of these molded packages can withstand several hundred temperature cycles from -40°C to +130°C without any degradation of their mechanical integrity