Power Performance Analysis III : Low Power Design Technology

Basic Assumption

(1) Technology : 0.35um CMOS process
(2) Operating Voltage : 2.5 V (Vt=0.5V) 2.0 V (Vt=0.4V) 1.5 V (Vt=0.3V) 1.0 V (Vt=0.2V)
(3) Operating Temperature : 25 C
(4) Circuit : Double Pass-Transistor Logic
(5) Worst Case Analysis : Mult 64 bit Floating Point

Power Estimation Method

(1) The power calculation is based on the paper, Carl Lemonds, "A High Throughput 16 by 16 Bit Multiplier for DSP Cores", IEEE International Symposium on Circuits and Systems, 1996. p479.
(2) The power calculation is also based on the paper, Uming Ko, Poras T. Balsara, and Wai Lee, "Low-Power Design Techniques for High-Performance CMOS Adders", IEEE TRANSCATIONS ON VLSI SYSTEMS, VOL. 3, NO. 2, JUNE 1995. P327 - P333.
(3) Transformation of Power Calculation in Fig 12 of the paper, Uming Ko.

Technology

Dual-Rail Domino Logic
2.5 V

Double Pass-Transistor
2.5 V

Double Pass-Transistor
2.0 V

Double Pass-Transistor
1.5 V

Double Pass-Transistor
1.0 V

0.6 uM Process
32bit Adder
@100MHz

50.345 mW

16.724 mW

11.300 mW

7.650 mW

3.448 mW

0.35 uM Process
32bit Adder
@100MHz

15.839 mW

5.262 mW

3.555 mW

2.407 mW

1.085 mW

relative Power Consumption

14.598

4.850

3.276

2.218

1.000

[ TABLE 5 ]


(4) Power Table 6 : Comparison with Various Low Power Design ( Limited on the worst case of Multiplication 64bit Floating Point )

0.35uM Process
64bit Floating Point

Normal
Dual-Rail Domino Logic
2.5 V

Enhanced
Dual-Rail Domino Logic
2.5 V

Enhanced
Double Pass Transistor
2.5 V

Enhanced
Double Pass Transistor
2.0 V

Enhanced
Double Pass Transistor
1.5 V

Enhanced
Double Pass Transistor
1.0 V

Sail Boat Allocation

190.68 mW

190.68 mW

63.34 mW

42.80 mW

28.97 mW

13.06 mW

16 bit Multiplier

2560.00 mW

N/A

N/A

N/A

N/A

N/A

32bit Wallace Tree

N/A

922.48 mW

306.44 mW

207.05 mW

140.17 mW

63.18 mW

48 bit Wallace Tree

108.88 mW

220.52 mW

73.25 mW

49.50 mW

33.51 mW

15.10 mW

48 bit CLA Adder

219.32 mW

N/A

N/A

N/A

N/A

N/A

96 bit Wallace Tree

53.95 mW

110.26 mW

36.63 mW

24.75 mW

16.75 mW

7.55 mW

96 bit CLA Adder

140.08 mW

N/A

N/A

N/A

N/A

N/A

128 bit CLA Adder

N/A

206.74 mW

68.68 mW

46.40 mW

31.41 mW

14.16 mW

96 bit FP Converter

37.77 mW

37.77 mW

12.32 mW

8.48 mW

5.74 mW

2.59 mW

Output Registers (FP)

8.41 mW

8.41 mW

2.74 mW

1.89 mW

1.28 mW

0.58 mW

Total Power (FP64)

3319.09 mW

1696.86 mW

563.58 mW

380.86 mW

257.84 mW

116.21mW

Relative Power (FP64)

100.00

51.12

16.98

11.47

7.77

3.50

[ TABLE 6 ]