"CMOS technology has scaled aggressively over the past few decades in an effort to enhance functionality, speed and packing density per chip. As the feature sizes are scaling down to sub-100nm regime, leakage power is increasing significantly and is becoming the dominant component of the total power dissipation. Major contributors to the total leakage current in deep submicron regime are subthreshold and gate tunneling leakage currents. The leakage reduction technique developed so far were mostly devoted to reducing subthreshold leakage. However, at sub-65nm feature sizes, gate leakage current grows faster and is expectedd to surpass subthreshold leakage current. In this work, an extensive analysis of the circuit level characteristics of subthreshold and gate leakage currents is performed at 45nm and 32nm feature sizes. The analysis provides several key observations on the interdependency of gate and subthreshold leakages currents. Based on these observations, a new leakage reduction technique is proposed that optimizes both the leakage currents. This technique identifies minimum leakage vectors for a given circuit based on the number of transistors in OFF state and their position in the stack. The effectiveness of the proposed technique is compared to most of the mainstream leakage reduction techniques by implementing them on ISCAS89 benchmark circuits. The proposed leakage reduction technique proved to be more effective in reducing gate leakage current than subthreshold leakage current. However, when combined with dual-threshold and variable-threshold CMOS techniques, substantial subthreshold leakage current reduction was also achieved. A total savings of 53% for subthreshold leakage current and 26% for gate leakage current are reported."--Abstract.

This book provides an in-depth overview of design and implementation of leakage reduction techniques. The focus is on applicability, technology dependencies, and scalability. The book mainly deals with circuit design but also addresses the interface between circuit and system level design on the one side and between circuit and physical design on the other side.

CD-ROM contains: AIM SPICE (from AIM Software) -- Micro-Cap 6 (from Spectrum Software) -- Silos III Verilog Simulator (from Simucad) -- Adobe Acrobat Reader 4.0 (from Adobe).

Covers in detail promising solutions at the device, circuit, and architecture levels of abstraction after first explaining the sensitivity of the various MOS leakage sources to these conditions from the first principles. Also treated are the resulting effects so the reader understands the effectiveness of leakage power reduction solutions under these different conditions. Case studies supply real-world examples that reap the benefits of leakage power reduction solutions as the book highlights different device design choices that exist to mitigate increases in the leakage components as technology scales.

The strong interaction between the demand for increasing chip functionality and data-processing speeds, and technological trends in the integrated circuit industry, like e.g. shrinking device geometry, growing chip area and increased transistor switching speeds, cause a huge increase in power dissipation for deep sub-micron digital CMOS circuits. Low-Power Deep Sub-micron CMOS Logic, Sub-threshold Current Reduction classifies all power dissipation sources in digital CMOS circuits and provides for a systematic approach of power reduction techniques. A clear distinction has been made between power dissipated to perform a calculation in a certain time frame, i.e. functional power dissipation, and power dissipated even when a circuit is idle, i.e. parasitical power dissipation. The threshold voltage level forms an important link between the functional and the parasitical power dissipation. Since for high data-processing speeds the threshold voltage needs to be low, whereas for low sub-threshold leakage currents it needs to be high. The latter is extremely important for battery operated circuits in standby modes. Therefore, a separate classification of sub-threshold current reduction techniques is presented showing existing and new circuit topologies. Low-Power Deep Sub-micron CMOS Logic, Sub-threshold Current Reduction is a valuable book for researchers, designers as well as students in the field of low-power digital design. Power dissipation is discussed from a fundamental, quantum mechanical and a practical point of view. Theory is accompanied with practical circuit implementations and measurement results.