Performance and power dissipation analysis for CCD memory systems

Abstract

In CCD memory systems a tradeoff exists between the frequency at which the memory system is operated and the power dissipation. The higher the frequency of operation, the lower is the service time and the higher is the power dissipation. A close look at the initial cost of the CCD memory system and the cost of maintaining these memory systems will show that the cost of maintenance for a year is nearly equal to the initial cost. This high cost necessitates an analysis of the CCD memory system design for service time and power dissipation.In this analysis three different states called the Access, Refresh, and Idle states are defined for a CCD memory system. Each state is characterized by a frequency and five different modes of operations are defined depending on the relation between the frequencies. Average service time and power dissipation equations are then derived and each mode is analyzed. Contrary to the normal belief that the power dissipation increases with access frequency, it is shown that for certain modes the power dissipation is constant and is independent of frequency. Finally, a figure of merit is defined and the different modes are compared.