12
COLIN STEVENS LOW POWER ELECTRONICS ELEC6270 INSTRUCTOR-VISHWANI D. AGRAWAL Very low voltage 16-bit counter in high leakage static CMOS technology

Very low voltage 16-bit counter in high leakage static CMOS technology

Embed Size (px)

DESCRIPTION

Very low voltage 16-bit counter in high leakage static CMOS technology. Colin Stevens Low Power Electronics Elec6270 Instructor- Vishwani d. Agrawal. Theory and Simulation. .18µm TSMC process in Design Architect Vth NMOS: .3725v / Vth Pmos: -.3948 |Vtp| + Vtn = .7673V - PowerPoint PPT Presentation

Citation preview

COLIN STEVENSLOW POWER ELECTRONICS

ELEC6270INSTRUCTOR-VISHWANI D. AGRAWAL

Very low voltage 16-bit counter in high leakage static CMOS

technology

Theory and Simulation

.18µm TSMC process in Design Architect Vth NMOS: .3725v / Vth Pmos: -.3948 |Vtp| + Vtn = .7673V

90 ns transient analysis Using ELDO Waveform Viewing in EZWAVE

Counter Selection

Asynchronous Advantages

Simple Design Utilizes Clock Gating Fast for small counters

Disadvantages Ripple Effect Delay Grows with

Counter Size

Synchronous Advantages

No Ripple Effect. Delay of all outputs are equal.

Disadvantages More Logic Required Flip Flops are clocked

even when no transition is required

Synchronous Counter

EZWAVE

Vdd = 1.2V

Power, Delay, and Frequency

Log Display and Power Delay Product

Results

Voltage Power % Reduction from

Optimal Voltage (1.2V)

Delay (ns)

% Reduction from Optimal

Voltage (1.2V)

5V 5.1264 mW -8482.62% 1.14 71.50%

4V 2.6631 mW -4358.56% 1.19 70.25%

3V 1.1481 mW -1822.15% 1.314 67.15%

2V 0.28895 mW -383.76% 1.89 52.75%

1.4V 90.81 nW -52.03% 3.18 20.50%

1.3V 74.226 nW -24.27% 3.68 8.00%

1.2V 59.73 nW 0.00% 4 0.00%

1.1V 48.232 nW 19.25% 5 -25.00%

1V 39.629 nW 33.65% 7 -75.00%

.9V 33.518 nW 43.88% 9 -125.00%

.77V 25.699 nW 56.97% 17 -325.00%

.76V 25.503 nW 57.30% 19 -375.00%

90ns Transient analysisFrequency

1/(delay + 10%)

(Mhz)

797.45

763.94

691.85

481

285.88

247.04

227.27

181.82

129.87

101.01

53.48

47.85

Sub-threshold Results

Voltage Power (nW) Delay (ns) Frequency

1/(delay + 10%)

0.6 20.60 88 10.33 Mhz

0.5 2.07 477 1.91 Mhz0.4 0.84 3,640 0.25 Mhz

0.3 0.34 30,700 29.61 Khz

0.2 0.20 245,000 3.71 Khz

0.1 0.09 1,880,000 480 Hz

Optimizations and Conclusions

Potential Optimization Low threshold gates could be used along the critical

path of and gates to make the circuit faster at lower voltages.

Conclusions Tradeoff between power and delay for a given circuit. I would like to have gotten the predictive models to

work.

References

Agrawal, V. D. (2007). Power Dissipation in CMOS Circuits [Power Point Presentation]. Retrieved from: http://www.eng.auburn.edu/users/agrawvd/COURSE/E6270_Spr09/LECTURES/lpd_4_CMOSPower.ppt

Counter. (nd) .Retrieved April 15, 2009, from Wikipedia Website: http://en.wikipedia.org/wiki/Counter Low-power electronics. (nd). Retrieved April 15, 2009, from Wikipedia Website:

http://en.wikipedia.org/wiki/Low-power_electronics Kulkarni, Vidya (nd). Logic Design Chapter – 5 [PowerPoint Presentation]. Retrieved from:

forum.vtu.ac.in/~edusat/Prog5/logd/vrk/Chapter-5.ppt

Questions?

Please don’t ask any questions.