Packaging and power distribution design considerations for a Sun Microsystems desktop workstation

Abstract

The power distribution system will become an increasingly important package design consideration for computer systems such as the Sun Microsystems desktop workstation, at least as important as simultaneous switch. Power distribution impedance is controlled by the switching power supply, bulk capacitance, ceramic capacitance and power plane properties at various portions of the frequency spectrum. A major concern with package power is resonance between chip capacitance and package inductance. The key parameters for package power are the core power supply loop inductance and the inductance and resistance used to connect any decoupling capacitors on the package. Decoupling capacitors on the package can be used but they will not be effective unless the connections to them are specially designed using aggressive technologies.