Low Power Design in CMOS

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Low Power Design in CMOS
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Why worry about power?-- Heat Dissipation
microprocessor power dissipation
source arpa-esto
DEC 21164
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Evolution in Power Dissipation
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Why worry about power Portability
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Where Does Power Go in CMOS?
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Dynamic Power Consumption
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Dynamic Power Consumption - Revisited
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Power Consumption is Data Dependent
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Transition Probabilities for Basic Gates
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Transition Probability of 2-input NOR Gate
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Problem Reconvergent Fanout
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How about Dynamic Circuits?
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4-input NAND Gate
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Transition Probabilities for Dynamic Gates
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Glitching in Static CMOS
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Example 1 Chain of NOR Gates
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Example 2 Adder Circuit
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How to Cope with Glitching?
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Short Circuit Currents
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Impact of rise/fall times on short-circuit
currents
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Short-circuit energy as a function of slope ratio
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Static Power Consumption
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Leakage
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Sub-Threshold in MOS
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Power Analysis in SPICE
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Design for Worst Case
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Reducing Vdd
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Lower Vdd Increases Delay
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Lowering the Threshold
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Transistor Sizing for Power Minimization
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Transistor Sizing for Fixed Throughput
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Reducing Effective Capacitance
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Summary