Memory Systems

CHAPTER 29

Power and Leakage

Power dissipation has become a top priority for today’s microprocessors. Previously a concern mainly for mobile devices, it has now become extremely important for general-purpose and even high-performance microprocessors, especially with the recent industry emphasis on processor “Performance-per-Watt.”

The power dissipated by typical modern circuits can be broken up into three main categories: dynamic or switching power, short circuit power, and leakage power. Dynamic power is due to the charging and discharging parasitic capacitance of transistors during logic transitions. This power is typically expressed in a simplified form:

(EQ 29.1)

where α is the average transition probability, C_tot is the total load capacitance ...