ABC, B.Tech. Electrical Engineering, XYZ univ, India

Statement of Purpose

After completing my B. Tech. in Electrical Engineering, I wish to pursue a degree of Ph.D. My main field of

interest is Mixed Signal Circuit Design. In future, I wish to pursue an academic profession in this domain.

During the course of my undergraduate degree, I have been involved in a variety of research projects in the

fields of circuit design, solid state devices and communication. This has allowed me to explore different fields

and find out which areas interest me the most. In the following paragraphs I describe some of the projects I

have worked on and how they have motivated me to pursue a PhD.

As a part of my undergraduate thesis, I am working on implementing object motion detection on chip. This

project is specifically aimed at applications such as collision avoidance in robotics and lane detection in

automobiles. FPGAs are the most commonly used hardware design platform in these cases, but they are not

particularly suitable for these applications which have power and space constraints. This project aims at

designing motion sensors using a novel binary imaging algorithm, where the image resolution is reduced by

using 1 bit imaging. Each pixel stores its previous binary value and compares the current value with it. This

way, frame subtraction is done at pixel level itself. Next, the overall information about change in pixels and

their current value is read out serially into ALU present on the same chip where motion is predicted based on

the changes in various pixels. During the project, the decision points involved selection of the memory

element, the comparator, the image pixel and the photodiode based on the constraints like maximizing fill

factor and minimizing static power dissipation. A software model was developed in Matlab as a proof of

concept. At present, the first iteration of motion detection at the rate of 100 frames per second is being tested

on Cadence. The chip will be fabricated in March, 2013.

As part of my “Solid State Device Physics” Course, I wrote a review paper on “Optimization Techniques for

performance improvement in FinFETs”. In this paper, I compared three types of techniques namely gate

controlled, geometry based and orientation based optimizations. Scaling down technology has introduced

problems of leakage currents, varying threshold voltages, reduced gate control, etc. Therefore, while

synchronous mode of gate control (front and back gate at a fixed offset) proved best for minimizing short

channel effects, unsynchronized mode provided freedom to vary threshold. Power minimization was done by

controlling the back gate like body (connecting to maximum and minimum potential for pMOS and nMOS

respectively). Similarly, geometry based optimizations appeared better for reducing contact resistance without

affecting short channel effects. Orientation optimizations included designing in <110> planes, which reduced

gate delay in pFinFETs. It was concluded that hybrid of these optimizations could provide the best design based

on specific application. Overall, the process of writing this review paper provided me an exposure to various

improvements done in the domain of FinFETs and helped me improve my paper reading and writing skills.

During my junior year, I got an opportunity to work at Bell Labs, India as a research intern. I worked on

implementing LTE parameters for 4G technology. The task was to emulate the channel on Ethernet (which

was later replaced by air transmission) and transfer data from Base Station to User Equipment in downlink

mode. The project was demonstrated by synchronously transmitting a video file from Base Station to User

Equipment. Code documentation was also improved upon for easy understanding in future. In the available

time frame of two and a half months, I was able to demonstrate single user downlink mode data transfer and

the future scope included extension to multiple users and base stations. This project helped me explore the

working environment in a large research group besides providing an exposure to communication side.

ABC, B.Tech. Electrical Engineering, XYZ univ, India

During my sophomore year, I joined Texas Instruments, India as a research intern. This was my first research

project. I wanted to explore the field of VLSI design and therefore opted to work on improving noise

performance of voltage controlled oscillators (VCOs). Based on literature survey, three main designs -

Colpitt’s oscillator, negative gm oscillator and tank circuit based oscillator were analyzed. Corner analysis

and noise simulations on Cadence were conducted and the best design was chosen to be Colpitt’s oscillator.

This project was extended to exploring power, hardware and speed optimizations of 7 bit Analog to Digital

Converters (ADC). Flash based ADCs are faster than Successive Approximation (SAR) based ADCs, but are

complex and power consuming. So, a hybrid model was designed using 3 bits using Successive Approximation

(SAR) implementation and 4 bits using flash based technique. This project laid down my foundation in the

domain of VLSI and founded my way for further exploration of the field.

Besides working for research projects, I have also performed consistently well in academics throughout my

undergraduate studies. After my sixth semester, I have a GPA of so and so on a scale of 10 and am presently

ranked first in the department and third in the institute. Based on excellence in academics, I have backed

Todai University scholarship worth 200,000¥ consecutively for last 3 years. I have also been awarded Xyz

univ Semester Merit Award consecutively for six semesters and the Inlaks Award for academic excellence

in XYZ univs which is given to only 10 students throughout the country. Previously, I received a Gold Medal

in Indian National Physics Olympiad, and the National Talent Scholarship. All these achievements have

motivated me to pursue further studies in my discipline.

My interest in research is derived from my passion to understand a topic in detail and think over it for exploring

its various dimensions. I have a deep interest in technology and wish to analyze any given problem from all

possible viewpoints. Therefore, I wish to continue research. Also, research provides an opportunity to gain

experience in academic field which will help me in better shaping of my academic career. All these things

motivate me to do research by pursuing a degree of Ph.D. in future.

My choice of area of interest is based on my experiences in various projects. I have done projects in the domains

of embedded systems, digital and analog circuit design, solid state devices and communication. I liked doing

every project, but in particular I enjoyed reviewing papers and working in domain of mixed signal circuit

design. Therefore I am currently working in this area in my undergraduate thesis. I have got good exposure to

the use of circuit design for image sensors during my undergraduate thesis project. In future, I am willing to

explore its use in other applications like short range wireless communications.

I feel ABC University is the best institution for me. It provides ample research opportunities and an environment

which is conducive for a top class research. There is a lot of research being carried out in the field of mixed

signal circuit design over here. In particular, I am interested in the work being carried out in So and so research

Lab. I have read the papers related to so and so project which employ Organic Solar cells for Energy Harvesting

and Ultra Low Power UWB receiver using on off keying, for power savings. I have also read papers for

mmWave applications like design of Class E power amplifiers and maximum gain ring oscillators. I am

interested in exploring further in these areas and, therefore, have a strong inclination to be a part of one of the

research groups associated to this lab.

My experiences during my internships and the thesis project have strengthened my fundamentals in circuit

design. Also, with time I have developed the essential skills for doing research. These include patience,

perseverance, diligence and positive thinking. These characteristics, added with my ability to generate new

ideas and work honestly to realize them, provide me an advantage for doing research. Moreover, my deep

interest to enter field of academia in future strengthens my determination to do a Ph.D. A good academic

record has bolstered my confidence and enthusiasm and motivated me enough to choose research as my future

profession. I believe these aspects make me a worthy candidate to be selected for a Ph.D.