1. Power Reduction Technique
Parallelism in circuits using duplication of logic
ELEC 6270
By Sreekumar Menon
Power Reduction Technique

2. OUTLINE Problem Definition Steps for Implementation
Background Information
Experimental Results
Theoretical Results
Conclusion
Lessons

3. 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

4. Block diagram Representation

5. Implementation Technique
MODELSim, Leonardo, Design Architect, Eldo
Technology used ami 0.5
Delay calculation( 50 % of the rise time)
VHDL/Verilog

6. Power versus voltage (N=1)
Dynamic Power (mW)
Static Power
(uW) 5
33.471 4
21.020 3
7.9665
11.658 2
3.7048
5.114 1
0.5181
1.256

7. Dynamic Power v/s Voltage (N=1)

8. 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

9. Dynamic Power v/s Voltage (N=2)

10. 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

11. Delay versus Voltage (N=1)

12. 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

13. 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

14. Theoretical Calculations
Power = CVDD2
The Delay versus Voltage graph can be used for interpolating the voltage levels for various degrees of parallelism

15. 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

16. 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

17. Lessons
Patience!!!!!!!!!!!!!!!!!!!!!!!!!

18. References
Dr Agrawal’s website
Mentor manuals

19. Thank You!!!!!