Responsibility of an Engineer

gilamonsterbirdsElectronics - Devices

Nov 24, 2013 (3 years and 11 months ago)

97 views

Environment Friendly Engineering: An Ethical
Responsibility of an Engineer



For

EEL 5344: Digital CMOS VLSI Design

Engineering Ethics



Engineering ethics



application of moral principles and professional standards to
situations encountered by professionals in the practice of engineering.

Engineers’ Responsibilities

Public

Client

Employer

Profession

Environment

Engineering Ethics (contd.)



Code of Ethics



Institute of Electrical and Electronics Engineers (IEEE)



We, the members of the IEEE, in recognition of the importance of our technologies in affecting the quality of life
throughout the world, and in accepting a personal obligation to our profession, its members and the communities
we serve, do hereby commit ourselves to the highest ethical and professional conduct and agree:


to accept responsibility in making decisions consistent with the safety, health and welfare of the public, and to
disclose promptly factors that might endanger the public or the
environment
;

to avoid real or perceived conflicts of interest whenever possible, and to disclose them to affected parties when
they do exist;

to be honest and realistic in stating claims or estimates based on available data;

to reject bribery in all its forms;

to improve the understanding of technology, its appropriate application, and potential consequences;

to maintain and improve our technical competence and to undertake technological tasks for others only if
qualified by training or experience, or after full disclosure of pertinent limitations;

to seek, accept, and offer honest criticism of technical work, to acknowledge and correct errors, and to credit
properly the contributions of others;

to treat fairly all persons regardless of such factors as race, religion, gender, disability, age, or national origin;

to avoid injuring others, their property, reputation, or employment by false or malicious action;

to assist colleagues and co
-
workers in their professional development and to support them in following this code
of ethics.


Environmental Hazards due to Electronics

Electronics

E
-
Waste

E
-
Waste



Formed by discarded electronic equipments like
monitors, CPUs, cell phones.



Contains the following toxic heavy metals and
chemicals,



Lead



Cadmium



Mercury



Beryllium



Hexavalent

Chromium



Polyvinyl Chloride (PVC) plastics



Brominated flame retardants

E
-
Waste (contd.)



Lead

Usage: soldering of electronic components like PCBs, capacitors, interconnects.

Hazard: damages the nervous system and kidneys, impairs brain development in
children.



Cadmium

Usage: as a semiconductor
,
batteries, stabilizers, switches.

Hazard: damage of kidneys and bones, heart disease, affects respiratory system.



Mercury

Usage: relays, switches, lamps, thermostats, batteries.

Hazard: affects central nervous system, hinders brain development,
cardiovascular diseases.


E
-
Waste (contd.)



Beryllium

Usage: motherboards for external connections.

Hazard: chronic beryllium disease (CBD), affects lungs.



Hexavalent Chromium

Usage: to prevent corrosion of steel and metal surfaces.

Hazard: carcinogenic, causes cancer



Polyvinyl Chloride (PVC) plastics

Usage: insulation of wires and cables.

Hazard: affects respiratory system.



Brominated flame retardants

Usage: to prevent combustion and spreading of flame.

Hazard: affects neurobehavioral development through mother’s milk.


Design for Environment DfE

Performance

Product Design

Production
Cost

Environment

Hazardous
materials

Design for Environment DfE (contd.)

Replacing the hazardous
materials

Design Adjustment

Selection of proper
replacement

Toxicology

Manufacturing Process

Reliability

Material properties

Economics &
Availability

Lead
-
free Electronics





Lead (Pb) is present as Tin Lead (SnPb) alloy for
soldering purposes at printed circuit boards (PCBs)



Possible replacement


Tin Silver Copper (SAC) alloy



Melting temperature



SnPb


187
o
C



SAC


217
-
218
o
C



High process temperature affects PCB design.


Lead
-
free Electronics (contd.)





PCB design factors for Lead
-
free assembly



change in the physical footprint.



change in surface mounted devices (SMDs) that
do not comply with the high process temperature
requirement.



change in placement and routing.



change in differential impedance calculation.


Legislations for the Environment





RoHS directive

along with WEEE directive



RoHS stands for

”the restriction of the use of certain hazardous substances in
electrical and electronic equipment” or simply Restriction of Hazardous
Substances.



WEEE stands for Waste Electrical and Electronic Equipment



created by the European Union.



took effect on July 1, 2006.



restricts 6 toxic materials used in electronics



lead



cadmium



mercury



hexavalent chromium



polybrominated biphenyl (PBB) flame retardant



polybrominated diphenyl ether (PBDE) flame retardant


Environmental Hazards due to Electronics

Electronics

E
-
Waste

Global Warming

Global Warming due to Electronics

Global warming

Emission of
greenhouse
gases

Fossil fuel
combustion

Electric power
Generation

Design energy efficient
electronic products


Energy Efficient Electronic Devices

What are the factors of energy efficient electronic devices


power consumption is less



power dissipation is less




does not get heated up





less damage to electronic parts

What are the advantages of energy efficient electronic devices


higher performance efficiency



lower maintenance cost





The main idea is to reduce power consumption and dissipation




Low Power Design



Low Power Design



Device level low power design



Electronic Devices use CMOS technology



Power dissipation in CMOS technology



Static power dissipation



when the device is OFF



leakage current



Dynamic power dissipation



when the device is ON



switching



Short
-
circuit power dissipation



when Vdd and Gnd are shorted

Low Power Design (contd.)



Static power dissipation



Leakage current



subthreshold leakage



gate leakage



gate induced drain leakage



reverse bias leakage



punchthrough




Design parameters



threshold voltage



channel length



gate oxide thickness



temperature


Low Power Design (contd.)



Dynamic power dissipation





Design parameters



switching activity (
a
)



supply voltage (Vdd)



clock frequency (Fclk)



load capacitance (CL)


Data Centers



Data center



facility for computing systems



servers



communication systems



storage systems



Functions



to store data



to perform efficient computation



Usage



World Wide Web providers



Software industries



Electronic design industries

Data Centers (contd.)



Microsoft’s data center in Quincy, Washington



Size



450,000 square feet.



computers are racked in five 12,000 foot
clusters.



1.5 tons of batteries.



600 miles of electrical wire.



Power consumption



consumes 48 megawatts of power.



enough to power approximately 40,000
homes.

Data Centers (contd.)



Energy efficient data center design



reduction of hardware.



designing compact multifunctional
circuits to minimize the size of
servers.



minimize the area.



efficient arrangement of devices.



streamlining power supplies.



streamlining communication cables.



designing efficient cooling systems.

Data Centers (contd.)



Blade servers



Design



designed by having only the essential parts



memory



processor



storage just enough to perform
efficient computing



discards other parts like power
supply, I/O interface, hard drive etc.



Makers



Sun, IBM, Intel



Advantages



compact, consumes less power, simplifies
expansion, low maintenance

Data Centers (contd.)



Green Grid



global consortium dedicated to advancing energy
efficiency in data centers and business computing
ecosystems.



Members



AMD, APC, Dell, HP, IBM, Intel, Microsoft,
Rackable Systems, SprayCool, Sun Microsystems
and VMware.



Actions



defining meaningful, user
-
centric models and metrics



developing standards, measurement methods,
processes and new technologies to improve data center
performance against the defined metrics



promoting the adoption of energy efficient standards,
processes, measurements and technologies.

Summary



Important ethical responsibility of an engineer



towards environment



E
-
Waste



Lead
-
free electronics



RoHS and WEEE directives



Global Warming due to energy consumption



Low power electronic design



Data centers