Power Reduction Technique Parallelism in circuits using duplication of logic ELEC 6270 By Sreekumar Menon Power Reduction Technique
OUTLINE Problem Definition Steps for Implementation Background Information Experimental Results Theoretical Results Conclusion Lessons
Problem Definition Design a 32 bit adder with parallelism Operational speed must be the same (throughput constant) Show it to be an effective Power reduction scheme
Block diagram Representation
Implementation Technique MODELSim, Leonardo, Design Architect, Eldo Technology used ami 0.5 Delay calculation( 50 % of the rise time) VHDL/Verilog http://www.amis.com/pdf/process_specifications/c5_ss.pdf
Power versus voltage (N=1) Dynamic Power (mW) Static Power (uW) 5 22.4128 33.471 4 13.1289 21.020 3 7.9665 11.658 2 3.7048 5.114 1 0.5181 1.256
Dynamic Power v/s Voltage (N=1)
Power versus voltage (N=2) Dynamic Power (mW) Static Power (uW) 3.5 18.095 56.18 3 12.775 48.11 2.5 9.0875 34.62 2 6.0511 22.01 1.5 2.2306 14.32
Dynamic Power v/s Voltage (N=2)
Delay versus Voltage (N=1) Voltage (Volts) Delay (Nano secs) 5 0.34 4 0.41 3 0.608 2 1.01 1 3.77
Delay versus Voltage (N=1)
Experimental Results Delay (nS) Voltage (N=1) Voltage (N=2) 0.34 5 3 0.41 4 2.5 0.608 1.5 1.01 2 NA
Power Reductions Reference voltage (V) Power (mW) (N=1) Voltage (V) (N=2) % Reduction 5 22.41 3 12.77 42.99 4 13.12 2.0 6.051 53.39 7.995 1.5 2.2306 72.17
Theoretical Calculations Power = CVDD2 The Delay versus Voltage graph can be used for interpolating the voltage levels for various degrees of parallelism
Theoretical v/s Experimental Voltage (Reference) V Theoretical Value (V) Experimental Value (V) Power Reduction (Theoretical)% Power Reduction (Experimental) % 5 3.2 3 52.40 42.99 4 2.3 2.5 64.60 53.39 1.4 1.5 78.12 72.17
Conclusions Parallelism is an effective power reduction technique However, it causes extra designing effort The theoretical calculations do not exactly match because the overhead hasn’t been taken into account in it
Lessons Patience!!!!!!!!!!!!!!!!!!!!!!!!!
References Dr Agrawal’s website Mentor manuals
Thank You!!!!!