Computer-Aided Design Techniques for Low Power Sequential Logic Circuits

1 Introduction.- 1.1 Power as a Design Constraint.- 1.2 Organization of this Book.- References.- 2 Power Estimation.- 2.1 Power Dissipation Model.- 2.2 Switching Activity Estimation.- 2.2.1 Simulation-Based Techniques.- 2.2.2 Issues in Probabilistic Estimation Techniques.- 2.2.3 Probabilistic Techniques.- 2.3 Summary.- References.- 3 A Power Estimation Method for Combinational Circuits.- 3.1 Symbolic Simulation.- 3.2 Transparent Latches.- 3.3 Modeling Inertial Delay.- 3.4 Power Estimation Results.- 3.5 Summary.- References.- 4 Power Estimation for Sequential Circuits.- 4.1 Pipelines.- 4.2 Finite State Machines: Exact Method.- 4.2.1 Modeling Temporal Correlation.- 4.2.2 State Probability Computation.- 4.2.3 Power Estimation given State Probabilities.- 4.3 Finite State Machines: Approximate Method.- 4.3.1 Basis for the Approximation.- 4.3.2 Computing Present State Line Probabilities.- 4.3.3 Picard-Peano Method.- 4.3.4 Newton-Raphson Method.- 4.3.5 Improving Accuracy using m-Expanded Networks.- 4.3.6 Improving Accuracy using k-Unrolled Networks.- 4.3.7 Redundant State Lines.- 4.4 Results on Sequential Power Estimation Techniques.- 4.5 Modeling Correlation of Input Sequences.- 4.5.1 Completely and Incompletely Specified Input Sequences.- 4.5.2 Assembly Programs.- 4.5.3 Experimental Results.- 4.6 Summary.- References.- 5 Optimization Techniques for Low Power Circuits.- 5.1 Power Optimization by Transistor Sizing.- 5.2 Combinational Logic Level Optimization.- 5.2.1 Path Balancing.- 5.2.2 Don't-care Optimization.- 5.2.3 Logic Factorization.- 5.2.4 Technology Mapping.- 5.3 Sequential Optimization.- 5.3.1 State Encoding.- 5.3.2 Encoding in the Datapath.- 5.3.3 Gated Clocks.- 5.4 Summary.- References.- 6 Retiming for Low Power.- 6.1 Review of Retiming.- 6.1.1 Basic Concepts.- 6.1.2 Applications of Retiming.- 6.2 Retiming for Low Power.- 6.2.1 Cost Function.- 6.2.2 Verifying a Given Clock Period.- 6.2.3 Retiming Constraints.- 6.2.4 Executing the Retiming.- 6.3 Experimental Results.- 6.4 Conclusions.- References.- 7 Precomputation.- 7.1 Subset Input Disabling Precomputation.- 7.1.1 Subset Input Disabling Precomputation Architecture.- 7.1.2 An Example.- 7.1.3 Synthesis of Precomputation Logic.- 7.1.4 Multiple-Output Functions.- 7.1.5 Examples of Precomputation Applied to Datapath Modules.- 7.1.6 Multiple Cycle Precomputation.- 7.1.7 Experimental Results for the Subset Input Disabling Architecture.- 7.2 Complete Input Disabling Precomputation.- 7.2.1 Complete Input Disabling Precomputation Architecture.- 7.2.2 An Example.- 7.2.3 Synthesis of Precomputation Logic.- 7.2.4 Simplifying the Original Combinational Logic Block.- 7.2.5 Multiple-Output Functions.- 7.2.6 Experimental Results for the Complete Input Disabling Architecture.- 7.3 Combinational Precomputation.- 7.3.1 Combinational Logic Precomputation.- 7.3.2 Precomputation at the Inputs.- 7.3.3 Precomputation for Arbitrary Sub-Circuits in a Circuit.- 7.3.4 Experimental Results for the Combinational Precomputation Architecture.- 7.4 Multiplexor-Based Precomputation.- 7.5 Conclusions.- References.- 8 High-Level Power Estimation and Optimization.- 8.1 Register Transfer Level Power Estimation.- 8.1.1 Functional Modules.- 8.1.2 Controller.- 8.1.3 Interconnect.- 8.2 Behavioral Level Synthesis for Low Power.- 8.2.1 Transformation Techniques.- 8.2.2 Scheduling Techniques.- 8.2.3 Allocation Techniques.- 8.2.4 Optimizations at the Register-Transfer Level.- 8.3 Conclusions.- References.- 9 Conclusion.- 9.1 Power Estimation at the Logic Level.- 9.2 Optimization Techniques at the Logic Level.- 9.3 Estimation and Optimization Techniques at the RT Level.- References.