Experimental Characterization of Simultaneous Switching Noise for Multichip Modules

CMOS-based multichip modules have been actively developed for achieving high performance and high speed systems. Simultaneous switching noise (SSN) induced by CMOS output buffers is a serious problem for both multichip modules (MCM's) and single-chip packages (SCP's); the problem must be solved in order to ensure stable operation and inherent speed performance. Multichip modules are expected to have a smaller switching noise level than SCP's due to the removal of the first-level package and its parasitics. This paper reports the results of switching noise measurements for different types of MCM's using a switching noise generating chip. Two types of test vehicles were fabricated and measurement results were compared. Noise distribution on a ground plane was also measured.