The Once and Future Computer:Post-Moore Mechanical Circuits

Matthew SpencerBEARS Symposium Lightning Talk

2014-02-13

Difference Engine (1842)

ENIAC (1946)

Power Prediction vs. Time (c. 2000)

4004

8008

8080

8085

8086

286386

486

Pentium® proc

P6

1

10

100

1000

10000

1970 1980 1990 2000 2010

Year

Pow

er

Den

sit

y (

W/c

m2)

Hot Plate

Nuclear Reactor

Rocket Nozzle

S. Borkar, Intel

Sun’s Surface

CMOS Minimum Energy/Op

Eleakage

Edynamic

Etotal

0.1 0.2 0.3 0.4 0.5

5

10

15

20

25

VDD (V)

Nor

mal

ized

Ene

rgy/

op

0 1 2 3 41/throughput

5 6

8

9

10

11

Nor

mal

ized

Ene

rgy/

op

1x

2x8x

More parallelism does not help

Transistor E/op vs. Supply Voltage

Processor E/op vs. Operating Frequency

Back to Mechanics: Improvement?Poly-SiGe

Tungsten

Measured I-V Curve

1 mVMeasurement Noise Floor

VS = VB = 0VD = 1

6.1210−14

VG (V)6.125 6.13

10−12

10−10

10−8

10−6

10−4

I DS (

A)

Energy vs. VDD

Etotal = Edynamic

0.1 0.2 0.3 0.4 0.5VDD (V)

Nor

mal

ized

E/o

p5

10

15

20

25

Edynamic

Etotal

Circuit Design Covers Device Flaws

• Problem: Mechanical motion is slow• Solution: Arrange relay circuits w/ only 1 delay

1 mechanical delay

NEMS: 12 relays

4 gate delays

CMOS: 30 transistors

CLICKR6 (2013)

CLICKR2 (2010)

Mechanical Circuits Could Be In Your Computer In 10 Years.