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Low-Power Design Techniques
in Digital Systems
Prof. Vojin G. Oklobdzija
University of California
November 19, 2003
Outline of the Talk
•
•
•
•
•
Power trends in VLSI
Scaling theory and predictions
Research efforts in power reduction
Efficiency measures and design guidelines
Latches and Flip-Flops for Low-Power
– Dual-Edge FFs
– SOI
• Conclusion: Low-Power perspective
2
Power trends in VLSI
3
“CMOS Circuits dissipate little power by nature. So believed circuit designers”
(Kuroda-Sakurai, 95)
100
Power (W)
x4 / 3years
10
1
0.1
0.01
80
85
90
95
“By the year 2000 power dissipation of high-end ICs will exceed the practical
limits of ceramic packages, even if the supply voltage can be feasibly reduced.”
(* Taken from Sakurai’s ISSCC 2001 presentation)
4
Gloom and Doom predictions
Source: Shekhar Borkar, Intel
5
6
Source: Shekhar Borkar, Intel
Power (Watts)
Power versus Year: taken from ISSCC, uP Report, Hot-Chips
80
RISC
70
High-end growing
at 25% / year
y = 2E-222e0.2574x
x86
Consumer
60
Dec Alpha
Expon. (RISC)
Expon. (x86)
50
Expon. (Consumer)
y = 3E-97e0.1131x
Expon. (Dec Alpha)
RISC @ 12% / yr
40
X86 @ 15% / yr
30
y = 2E-124e0.1442x
20
Consumer (low-end)
At 13% / year
y = 6E-109e0.126x
10
0
1995.5
Year
1996
1996.5
1997
1997.5
1998
1998.5
1999
1999.5
2000
2000.5
7
VDD, Power and Current Trend
Voltage
Voltage [V]
2
Power
1.5
Current
1
0.5
0
1998
2002
2006
2010
500
Power per chip [W]
200
0
2014
VDD current [A]
2.5
0
Year
International Technology Roadmap for Semiconductors 1999 update sponsored by the Semiconductor
Industry Association in cooperation with European Electronic Component Association (EECA) ,
Electronic Industries Association of Japan (EIAJ), Korea Semiconductor Industry Association (KSIA),
8
and Taiwan Semiconductor Industry Association (TSIA)
(* Taken from Sakurai’s ISSCC 2001 presentation)
Power Delivery Problem (not just California)
Your car
starter !
Source: Shekhar Borkar, Intel
9
Trend in L di/dt
• di/dt is roughly proportional to
I * f, where I is the chip’s current and f is the clock frequency
or I * Vdd * f / Vdd = P * f / Vdd, where P is the chip’s
power.
• The trend is:
P
f
Vdd
on-chip L
package L slightly decreases
• Therefore, L di/dt fluctuation increases
significantly.
(* Taken from Norman Chang, HP)
10
ISPEC^2/Watt vs Feature Size (microns)
ISPEC^2/Watt
100
Energy-Delay product
is improving more
than 2x / generation
y = 0.3733x-2.5778
Saving Grace !
10
1
0.00
0.20
0.40
0.60
Feature Size (microns)
11
ISPEC^2/Watt vsYear
100 Consumer
X86 efficiency
90
x86
improving
80
dramatically
70 Server 4X / generation
60
High-End
processors
50
efficiency not
improving
40
30
20
10
0
1995 1996 1997 1998
average improving
3X / generation
Year
1999
2000
2001
12
Scaling theory and predictions
13
The power dissipation has increased 1000 times over the 15 years
and is exceeding 70 Watts
Scaling principles:
1. A “constant field scaling” theory [Dennard] assumes that device
voltages as well as device dimensions are scaled by a scaling
factor x (>1), resulting in a constant electric field in a device:
 power density remains constant
 circuit performance can be improved in terms of:
 density x2
 speed x
 power 1/ x2
 power-delay product 1/ x3
Limitless progress in CMOS is promised with this scaling scenario
14
In practice neither a supply voltage nor a threshold voltage
had been scaled till 1990 leading to the theory of:
“Constant voltage scaling” which assumes the constant voltage
This assumption yields:
• speed improvement by x2
• power density increases rapidly by x3
15
The constant field is not realistic, x0.5 is satisfactory - however even with that
the power dissipation would exceed ECL by 2001: a new philosophy is required !
(* Taken from Sakurai and Kuroda, IEICE 95 paper)
16
High-Performance View Point on Power
*taken from Ron Preston, DEC Alpha
P=k C V2 f :
• Shrinking to the new technology (30% reduction in l)
– C decreases by 30%
– f increases by 1/0.7 = 43%
– Pnew=0.7 (1/0.7) Pold = Pold
(No Change in Power ! )
• New design:
– Double the No. of devices
– Pnew=2 x 0.7 (1/0.7) Pold = 2 X Pold (Power Doubles !)
Scale Vdd by 30% in the new design:
– Pnew=2 x 0.7 (1/0.7) (0.7)2Pold = Pold (Power stays constant !)
17
High-Performance View Point on Power
*taken from Ron Preston, DEC Alpha
Reality:
Chip
l
Vdd
Freq.
Power
21164
05u
3.3V
300MHz
50W
21264
0.35u
2.0V
600MHz
72W
Change
-30%
-39%
+100%
+44%
Paradigm Changes: More Aggressive Circuits, Toggle rate
increasing, Out of Order, Speculative Execution
What to Expect: Power will be limited by the package and cooling
techniques
Frequency will be determined by the power - as high as package can
take !
18
Research Efforts in Low-Power Design
Reduce the active load:
•Minimize the circuits
•Use more efficient design
•Charge recycling
•More efficient layout
Technology scaling:
•The highest win
•Thresholds should scale
•Leakage starts to byte
•Dynamic voltage scaling
Psw = k CL V2cc fCLK
Reduce Switching Activity:
•Conditional clock
•Conditional precharge
•Switching-off inactive
blocks
•Conditional execution
Run it slower:
•Use parallelism
•Less pipeline
stages
•Use double-edge
flip-flop
19
Reducing the Power Dissipation
• The power dissipation can be minimized by
reducing:
• supply voltage
• load capacitance
• switching activity
– Reducing the supply voltage brings a quadratic
improvement
– Reducing the load capacitance contributes to the
improvement of both power dissipation and circuit
speed.
20
Voltage Scaling
There are three means to maintain the throughput:
• Reduce Vth to improve circuit speed
• Introduce parallel and pipelined architecture while
using slower device speeds
(assumes limitless no. of transistors, in reality the transistor density is
only increasing by 60% per year)
• Prepare multiple supply voltages and for each cluster
of circuits choose the lowest supply voltage that satisfies
the speed.
(A good level converter is necessary which exhibits small delay and consumes
little power, small area)
21
22
Is there an optimal design point ?
23
Power Dissipation and Circuit Delay
Power :
V th
2
P = pt •f CLK • CL • VDD + I 0 •10
S
Delay
VDD
•
-4
1
5
0.8
Power (W)
k•Q
I
=
k • CL • VDD
a
(VDD - Vth )
( a=1.3)
-10
x 10
x 10
4
Delay (s)
0.6
0.4
=
A
0.2
B
0
4
3
2
1
04
3
2
10.8
(* Taken from T. Sakurai)
0.4
0
-0.4
3
A
B
2
1 0.8 0.4
-0.4
0
24
Power-Delay Product, Energy-Delay Product
Lowest Voltage –
Highest Threshold –
no optimum
(*from Sakurai, Kuroda, IEICE 95 paper)
•Power-Delay Product is a misleading measure; it will always favor a
processor that operates at lower frequency
•Energy-Delay is more adequate - but Energy-Delay2 should be used
25
Power-Delay Product, Energy-Delay Product
Horowitz, Indermaur, Gonzales argue against Power-Delay, SLPE’94
26
Energy-Delay**2
(*courtesy of Prof. T. Sakurai)
27
Energy-Delay Product vs. Energy-Delay**2
Nowka, Hofstee, Carpenter of IBM argue against Energy-Delay
as a design efficiency measure (private communication)
28
Energy-Delay Product vs. Energy-Delay**2
Optimal point:
(due to to Vth
being fixed ?)
The same
design should
have relatively
the same
efficiency
Nowka, Hofstee, Carpenter of IBM argue against Energy-Delay
as a design efficiency measure (private communication)
29
Feature
601+
604
620
100
100
133
(100)
Diff.
Frequency
MHz
CMOS Process
.5u 5-metal
.5u 4-metal
.5u 4-metal
same
~same
Cache Total
32KB Cache
64K
~same
Load/Store Unit
No
16K+16K
Cache
Yes
Dual Integer Unit
No
Yes
Yes
Register Renaming
No
Yes
Yes
Peak Issue
2 + Br
4 Insts
4 Insts
~double
Transistors
2.8 Million
3.6 Million
6.9 Million
+30% /+146%
SPECint92
105
160
+50% /+61%
SPECfp02
125
165
Power
4W
13W
26.5/31.2
12.3/12.7
225
(169)
300
(225)
30W
(22.5W)
7.5/10
4.0E-6
13.0E-6
12.8E-6
(PF/Trans)*E12
1.43
3.61
1.86
IPC
1.05
1.6
1.69
PE*IPC**3 (*E6)
4.01
12.98
12.69
PE=Watt/Spec**3
3.46E-6
3.17E-6
2.63E-6
Spec/Watt
PF=Watt/Freq**3
Yes
Example:
PowerPC
+30% /+80%
+225%/+463%
-115%/
-252%
30
Feature
Digital
21164
MIPS 10000
PowerPC
620
500 MHz
200 MHz
200 MHz
180 MHz
250 MHz
Pipeline Stages
7
5-7
5
7-9
6-9
Issue Rate
4
4
4
4
4
6 lds
32
16
56
none
Register Renam. (int/FP)
none/8
32/32
8/8
56
none
Transistors/
Logic transistors
9.3M/
1.8M
5.9M/
2.3M
6.9M/
2.2M
3.9M*/
3.9M
3.8M/
2.0M
12.6/18.3
8.9/17.2
9/9
10.8/18.3
8.5/15
25W
30W
30W
40W
20W
SpecInt/
Watt
0.5
0.3
0.3
0.27
0.43
1/Energy*Delay
6.4
2.6
2.7
2.9
3.6
Watt/Freq**3
0.2E-6
3.75E-6
3.75E-6
6.86E-6
1.28E-6
(PF/Trans)*E12
0.022
0.64
0.54
1.76
0.34
(PF/LTrans)*E12
0.11
1.63
1.7
1.76
0.64
12.5E-3
42.5E-3
41.5E-3
31.7E-3
32.5E-3
Freq
Out-of-Order Exec.
SPEC95
(Intg/FlPt)
Power
Watt/Spec**3
HP 8000
Sun
Ultra-Sparc
31
Sensitivity to Vth fluctuation
ΔVTH =
1.8
Normalized Delay
VDD =1.0 V
±0.15V
1.5 V
±0.05V
1.4
3.0 V
1.0
0.6
(* Taken from T. Sakurai)
5.0 V
0
0.2
0.4
0.5
VTH (V)
0.7
1
32
Use of Different Circuits Families
33
Capacitance Reduction
The load capacitance is the sum of:
• gate capacitance
• diffusion capacitance
• routing capacitance
Using small number of transistors, or small size of transistors
contributes to the reduction in the gate capacitance and the
diffusion capacitance.
Pass transistor logic may have advantage because it
comprises fewer transistors and exhibits smaller stray
capacitance than conventional static CMOS logic.
34
Pass-Transistor Logic
35
Pass-Transistor Logic:
CVSL, CPL, SRPL, DSL, DPL, DCVSPG
36
SAPL:
Sense-Amplifying Pass-transistor Logic
All nodes are first discharged and then evaluated by inputs.
Outputs are 100mV above GND
37
Where does the power go ?
38
Power use is different from chip to chip:
(*from Sakurai, Kuroda, IEICE 95 paper)
MPU1 is a low end microprocessor
MPU2 is a high-end CPU with large cache
ASSP1 is MPEG-2 decoder
ASSP2 is an ATM switch
39
Design Example: Strong Arm 110
Two power modes: idle and sleep
Power:
0.5W using 1.1V internal PS: 184 Drystone/MIPS @162MHz
1.1W using 2V internal PS: 245 Drystone/MIPS @ 215MHz
Power Breakdown:
I-Cache
D-Cache
I-Unit
Exec-Unit
I-MMU
D-MMU
Clock
Others
*from D. Dobberpuhl
27%
16%
18%
8%
9%
8%
10%
4% (PLL < 1%)
40
Design Example: Strong Arm 110
*from D. Dobberpuhl
41
Design Example: Strong Arm 110
*from D. Dobberpuhl
*from D. Dobberpuhl
However, leakage currents starts to affect stand-by power
42
Controlling both: VDD and VTH
for low power
43
Controlling VDD and VTH for low power
Low power  Low VDD  Low speed  Low VTH  High leakage  VDD-VTH control
Multiple V TH
Variable VTH
Multiple V DD
Variable VDD
Active
Dual-VTH
VTH hopping
Dual-VDD
VDD hopping
Stand-by
MTCMOS
VTCMOS
Boosted gate MOS
Software-hardware cooperation
Technology-circuit cooperation
*) MTCMOS: Multi-Threshold CMOS
*) VTCMOS: Variable Threshold CMOS
• Multiple : spatial assignment
• Variable : temporal assignment
(* from Prof. T. Sakurai)
44
Dual-VTH concept
Low-VTH circuit
(High leakage)
High-VTH circuit
(Low leakage)
Critical paths
Non-critical paths
(* from Prof. T. Sakurai)
45
Clustered Voltage Scaling for Multiple VDD’s
Conventional Design
CVS Structure
FF
FF
FF
FF Level-Shifting F/F
FF
FF
FF
FF
FF
FF
FF
FF
FF
FF
FF
FF
FF
FF
FF
FF
FF
Critical Path
Critical Path
Lower VDD portion is shown as shaded
Once VL is applied to a logic gate, VL is applied to subsequent logic
gates until F/F’s to eliminate DC current paths. F/F’s restore VH.
M.Takahashi et al., “A 60mW MPEG4 Video Codec Using Clustered Voltage Scaling with
Variable Supply-Voltage Scheme,” ISSCC, pp.36-37, Feb.1998.
(* from Prof. T. Sakurai)
46
If you don’t need to hussle,
VDD should be as low as possible
VDD should be lowered
to the minimum level
which ensures
the real-time operation.
1.0
Normalized power
Energy consumption is
proportional to
the square of VDD.
0.8
0.6
0.4
0.2
0.0
0.0
(* from Prof. T. Sakurai)
Variable Vdd
Fixed Vdd
0.2
0.4
0.6
0.8
Normalized workload
1.0
47
Measured voltage waveforms
V DDmax =8% on average
V DDmax
V DDmin
V DD
1 sync frame
200ms
Sleep signal
Sleep
Sleep=6% on average
(* from Prof. T. Sakurai)
48
Measured power characteristics
Total power = 0.8W x 0.08 + 0.16W x 0.86 + 0.07W x 0.06 = 0.2W
Power: P [W]
1
0.8W
0.8
Time for VDDmax: 8%
Down ƒ=200MHz
to 1/5
0.6
0.4
0.2
ƒ=100MHz
Time for VDDmin: 86%
0.16W
Time for sleep: 6% 0.07W
0
0
1
2
Supply voltage: V DD [V]
VDD hopping can cut down power consumption to 1/4
(* from Prof. T. Sakurai)
49
Simulation results
MPEG-2 video decoding
VSELP speech encoding
0.40
0.28
RPC: 2 levels (f,f/2)
RPC: 3 levels (f,f/2,f/3)
RPC: 4 levels (f,f/2,f/3,f/4)
RPC: infinite levels
post-simulation analysis
0.24
0.20
Normalized Power P/PFIX
Normalized Power P/PFIX
0.32
0.16
0.12
0.08
0.35
0.30
0.25
0.20
0.15
0.10
0.04
0.05
0.00
0.00
0.0
0.2
0.4
0.6
0.8
Transition Delay T (ms)
TD
(* from Prof. T. Sakurai)
1.0
RPC: 2 levels (f,f/2)
RPC: 3 levels (f,f/2,f/3)
RPC: 4 levels (f,f/2,f/3,f/4)
RPC: infinite levels
post-simulation analysis
0.0
0.2
0.4
0.6
0.8
1.0
Transition Delay T (ms)
TD
50
Aggressive Voltage Scaling
*Taken from Kuroda
If we can dynamically scale Vdd and Vth the advantage is obvious
51
Example
52
TransMeta Example
*Taken from Doug Laird’s presentation, January 19 th 2000
53
TransMeta Example
*Taken from Doug Laird’s presentation, January 19 th 2000
54
TransMeta Example
*Taken from Doug Laird’s presentation, January 19 th 2000
• “Code Morphing” is another contributor to power reduction
since it eliminates unnecessary external memory access
55
TransMeta Example
56
Latches and Flip-Flops for Low-Power
57
Simulation Condition and Testbench
Timing
Data In
D
 Total FF overhead is setup +
clock-to-output time
 Circuit optimization
towards td-q
 Clock skew robustness
obtained from observing
DQ curve
SET
14X min
inv
Q
Clk
CLR
Clock
14X min
inv
Q
14X min
inv
t d  min (t DQ )
t DCLK
Power-Delay Product
 Overall performance
parameter at fixed
frequency
PDP(at fixed f)  EDP  t d  Pdiss
58
Flip-Flop Performance Comparison
Data
D
Q
Test bench
Clock
• Total power consumed
– internal power
– data power
– clock power
• Measured for four cases
Clk Q
200fF
200fF
50fF
Delay is (minimum D-Q):
Clk-Q + Setup time
– no activity (0000… and 1111…)
– maximum activity (0101010..)
– average activity (random sequence)
59
OLD TEST BENCH
OLD TEST BENCH:
• Total Power = Drivers
Power + Test Unit Power
• PDP- Optimized = Equal
Trade-off on Power and
Delay
• Improper Load on Drivers
NEW TEST BENCH:
• Drivers: Fixed Gain and
Driving Test Unit Only
• Data-to-Output Delay
NEW TEST BENCH
• PD2P Optimized = Best
for Constant-Field Scaling
60
Comparison in terms of speed and EDPtot
Technology: 0.2u, Vdd=2V, T=20oC, measured @ 100MHz
• Delay: below 200ps
• SDFF
• HLFF
• K-6 ETL
– 200-300ps
• PowerPC latch
• 21264 Alpha FF
• Strong Arm FF
• mC2MOS latch
•
187ps
199ps
200ps
266ps
272ps
275ps
292ps
– above 500ps
•
•
•
•
SSTC latch
DSTC latch
SSTC* latch
DSTC* latch
PDPtot @100MHz
– below 30fJ
• PowerPC latch
28fJ
– 30 - 50fJ
•
•
•
•
•
HLFF
SDFF
mC2MOS latch
21264 Alpha FF
Strong Arm FF
29fJ
39fJ
40fJ
43fJ
45fJ
– 50 - 70fJ
592ps
629ps
898ps
1060ps
• K-6 ETL
70fJ
– above 70fJ
• SSTC latch
• DSTC latch
95fJ
125fJ
61
Delay comparison
350
300
Delay [ps]
250
200
150
100
50
0
SDFF
HLFF
K6
PowerPC
Alpha 21264 Strong Arm
FF
FF
mC2MOS
• F-F design brings the fastest structures
62
Delay comparison
700
Delay [ps]
600
500
400
300
200
100
0
K6
SA-F/F
StrongArm
SSTC
DSTC
350
Delay [ps]
300
• F-F design brings
the fastest structures
250
200
150
100
50
0
SDFF
HLFF
PowerPC mC2MOS
63
Overall ranking
PDPtot ranges @100MHz
Activity=0.25 equal
transition probability
350
PDPtotal [fJ]
300
250
200
150
100
50
0
HLFF
SDFF
Pow erPC mC2MOS
Strong
Arm
Alpha
21264
K6
SSTC
DSTC
SSTC*
DSTC*
• EDPtot accepted as the overall cost function
• Proposed “low-power” latches from Yuan & Svensson, compared with
other presented structures do not show advantage, (the optimization
was not properly done - optimization is yet to be repeated under
different setup)
64
Overall ranking, zoomed
Activity=0.25 equal transition probability
80
70
60
PDPtot [fJ]
50
40
30
20
10
0
HLFF
SDFF
Pow erPC
mC2MOS
Strong Arm
Alpha
21264
K6
• Real signals have the activity between 0 and 1.0 ()
• Precharged hybrid structures are the fastest but their power
consumption strongly depends on the probability of “ones”
• More “ones” above the  point
65
Overall performance
160
60
140
50
PDPtot [fJ]
PDPtot [fJ]
120
40
30
100
80
60
20
40
10
20
0
0
SA-F/F
HLFF
SDFF
PowerPC
Activity=0.5 equal transition probability
mC2MOS
Strong
Arm110
K6
SSTC
DSTC
Activity=0.5 equal transition probability
• Real signals have the activity between 0 and 1.0 ()
• Precharged hybrid structures are the fastest but their power
consumption strongly depends on the probability of “ones”
• More “ones” above the  point
66
Conventional Clk-Q vs. minimum D-Q
400
HLFF
Total power [uW]
350
PowerPC
300
Strong Arm FF
250
200
Alpha 21264 FF
150
mC2MOS latch
100
K6 ETL
50
0
150
SSTC
200
250
300
350
400
450
500
550
600
Delay [ps]
HLFF
350
Total Power [uW]
DSTC
SDFF
400
PowerPC
300
•
Strong Arm FF
250
200
Alpha 21264 FF
150
mC2MOS latch
100
K6 ETL
50
0
100
650
•
Hidden positive setup
time
Degradation of Clk-Q
SSTC
150
200
250
Clk-Q delay [ps]
300
350
DSTC
SDFF
67
Internal Power distribution
Internal Power [uW]
400
350
300
250
200
150
100
50
0
Random,
activity=0.5
…01010101…
activity=1
…11111111…
activity=0
…00000000…
activity=0
Data patterns
HLFF
SDFF
PowerPC 603 latch
mC2MOS latch
StrongARM FF
Alpha 21264 FF
K6 ETL
•
Four sequences characterize the boundaries for internal power consumption
–
–
–
–
…010101…
random, equal transition probability,
…111111…
…000000…
maximum
average
precharge activity
leakage + internal clock processing
68
Comparison of Clock power consumption
DSTC MS latch
SSTC MS latch
K6 ETL
StrongArm FF
SA-F/F
mC2MOS
PowerPC MS latch
SDFF
HLFF
0
10
20
30
40
50
Local Clock power consumption [W]
69
Using Dual-Edge Flip-Flop
(run at ½ of the frequency
save on the power consumed in
clock distribution tree)
70
Dual-Edge vs. Single-Edge Flip-Flops
Comparison
Delay [ps]
Total Power [W]
400
350
350
300
300
250
200
150
100
DETFF1
DETFF2
DETFF3
SDFF
HLFF
PowerPC
250
200
150
100
50
50
0
0
•Fujitsu 0.18u process; Clock frequency 500MHz (250MHz for Dual Edge FFs)
•Data activity ratio a = 0.5
•VDD = 1.8V
•Temp = 25º
DETFF1
DETFF2
DETFF3
SDFF
HLFF
PowerPC
71
Dual-Edge vs. Single-Edge Flip-Flops
Comparison
Internal Power [W]
Clock Power [W]
300
60
250
50
DETFF1
DETFF2
DETFF3
SDFF
HLFF
PowerPC
200
150
100
DETFF1
DETFF2
DETFF3
SDFF
HLFF
PowerPC
40
30
20
50
10
0
0
Data Power [W]
25
20
15
10
5
0
DETFF1
DETFF2
DETFF3
SDFF
HLFF
PowerPC
•Fujitsu 0.18u process;
Clock frequency
500MHz (250MHz for
Dual Edge FFs)
•Data activity ratio a =
0.5
•VDD = 1.8V
•Temp = 25º
72
Silicon on Insulator (SOI) Technology
73
SOI Comparison
70
140
60
120
50
100
40
80
30
60
20
40
10
20
0
50
45
40
35
30
25
20
15
10
5
0
0
Delay [ps]
Internal Power [uW]
160
6
140
5
120
Clock Power [uW]
HAL
PowPC
HLFF
SDFF
SAFF
SA 110
4
100
3
80
60
2
40
1
20
0
Total Power [uW]
0
EDP [fJ]@500Mhz
F= 1GHz, a = 0.5, Le = 0.08 m, VDD=1.3V, T = 25C
74
In conclusion….
What can we expect that low power
will bring to us ?
75
Wearable Computer
76
Wearable Computer
77
Wearable Computer
78
Digital Ink
79
Implantable Computer
80
Bluetooth
81
Year 2010
Extrapolation of the trend with some saturation
Many important interesting application
Home, Entertainment, Office, Translation , Health care
Year 2020???
More assembly technique: 3D
Year 2110
Combination of bio and semiconductor
Brain
Sensor
Infrared
Humidity
CO2
Ultra small volume
Small number of neuron cells
Extremely low power
Real time image processing
(Artificial) Intelligence Long lifetime
3D flight control
by DNA manipulation
Bio-computer
82
Mosquito