Low-power CMOS digital design focuses on reducing power consumption while maintaining computational throughput. Techniques include using the lowest possible supply voltage, architectural, logic, circuit, and technology optimizations. An architectural-based scaling strategy shows that the optimal voltage is much lower than previously determined, achieved by trading increased silicon area for reduced power consumption. Portable applications demand high throughput and low power, challenging traditional battery technology. Future applications, such as universal multimedia access, require significant power for video compression, decompression, and speech recognition. Power consumption is critical in portable systems due to limited battery life. Power dissipation in CMOS circuits comes from switching, short-circuit, and leakage currents. The switching component is dominant in well-designed circuits, and low-power design aims to minimize it. The power-delay product is crucial for comparing circuit styles, with energy per transition given by $ C_{effective}V_{dd}^2 $. Circuit design considerations include dynamic vs. static logic, pass-gate vs. conventional CMOS, and synchronous vs. asynchronous timing. Dynamic logic has advantages in reducing switching activity and parasitic capacitance but has higher activity factors. Pass-gate logic uses fewer transistors and is more efficient for arithmetic functions. Threshold voltage scaling reduces power but increases subthreshold leakage. A threshold of at least 0.2 V is recommended to balance current drive and leakage. Power-down strategies in synchronous designs involve disabling unused units, while self-timed logic inherently reduces power by only transitioning when needed. Voltage scaling reduces power but increases delay. The power-delay product improves with lower voltages, but delays increase as voltage approaches device thresholds. Optimizing transistor sizing and using parallel or pipelined architectures can compensate for reduced speeds, allowing lower voltages and power savings. Architecture-driven voltage scaling determines the optimal supply voltage based on technology, architecture, and noise margin constraints. Parallel and pipelined architectures enable lower voltages by increasing parallelism and reducing overhead. The optimal voltage is typically around 1.5 V for 2.0-μm technology, with significant power savings. Factors such as algorithmic constraints, noise margins, and system requirements limit the lowest achievable voltage. Sequential algorithms and feedback mechanisms may restrict parallelism. However, the goal remains to operate at the lowest possible voltage and slowest speed to minimize power consumption.Low-power CMOS digital design focuses on reducing power consumption while maintaining computational throughput. Techniques include using the lowest possible supply voltage, architectural, logic, circuit, and technology optimizations. An architectural-based scaling strategy shows that the optimal voltage is much lower than previously determined, achieved by trading increased silicon area for reduced power consumption. Portable applications demand high throughput and low power, challenging traditional battery technology. Future applications, such as universal multimedia access, require significant power for video compression, decompression, and speech recognition. Power consumption is critical in portable systems due to limited battery life. Power dissipation in CMOS circuits comes from switching, short-circuit, and leakage currents. The switching component is dominant in well-designed circuits, and low-power design aims to minimize it. The power-delay product is crucial for comparing circuit styles, with energy per transition given by $ C_{effective}V_{dd}^2 $. Circuit design considerations include dynamic vs. static logic, pass-gate vs. conventional CMOS, and synchronous vs. asynchronous timing. Dynamic logic has advantages in reducing switching activity and parasitic capacitance but has higher activity factors. Pass-gate logic uses fewer transistors and is more efficient for arithmetic functions. Threshold voltage scaling reduces power but increases subthreshold leakage. A threshold of at least 0.2 V is recommended to balance current drive and leakage. Power-down strategies in synchronous designs involve disabling unused units, while self-timed logic inherently reduces power by only transitioning when needed. Voltage scaling reduces power but increases delay. The power-delay product improves with lower voltages, but delays increase as voltage approaches device thresholds. Optimizing transistor sizing and using parallel or pipelined architectures can compensate for reduced speeds, allowing lower voltages and power savings. Architecture-driven voltage scaling determines the optimal supply voltage based on technology, architecture, and noise margin constraints. Parallel and pipelined architectures enable lower voltages by increasing parallelism and reducing overhead. The optimal voltage is typically around 1.5 V for 2.0-μm technology, with significant power savings. Factors such as algorithmic constraints, noise margins, and system requirements limit the lowest achievable voltage. Sequential algorithms and feedback mechanisms may restrict parallelism. However, the goal remains to operate at the lowest possible voltage and slowest speed to minimize power consumption.