A low-cost multichip (MCM-L) packaging solution

The concept of multichip module on laminated substrates (MCM-L) is being used in addressing high speed problems at a cost effective manner. One of the major problems associated with high speeds is the delta-I noise or the Ldi/dt noise due to the simultaneous switching of multiple outputs in digital circuits. An MCM-L layout approach that helps in reducing the signal delays, as well as decreasing the Ldi/dt noise by reducing the effective ground inductance without the use of a separate ground plane is described. Modeling and analytical techniques are used to characterize the ground path inductance in a single chip package, and to define the width of the ground trade in the MCM-L for optimal ground path inductance