Copyright
IIT Kharagpur
Sougata Kumar Kar
VILL & POST: SUKRULAPUR, DIST: EAST MEDINIPUR, PIN: 721302, WB, INDIA.
Email: [email protected], [email protected] Ph: +91‐9433280223
Objective: Contributing significantly to the field of engineering and technology being a part of a reputed organization where I can share and enrich my knowledge.
Current Status: PhD, Electrical Engineering, IIT Kharagpur. Thesis defended – January, 2013.
Highlights of Educational Career
I. PhD – Dept. of Electrical Engineering, IIT Kharagpur.
Research Experience:
• Analog integrated circuit design, Linearization of OTA, Op‐amp, Band‐gap reference, Tunable signal generators, Continuous‐time Gm‐C filters, etc.
• Capacitive sensor interfacing circuit for MEMS accelerometer, Switched capacitor amplifiers, Integration and testing of MEMS sensor and ASIC.
• Taped out designs in 0.18µm UMC CMOS process technology.
II. Master of Technology ‐ From the Dept. of Instrumentation and Electronics Engineering, Jadavpur University, West Bengal, 2006, CGPA: 9.02/10.
III. Bachelor of Technology ‐ From the Dept. of Instrumentation Engineering, Haldia Institute of Technology, West Bengal, 2000, Marks: 76.5/100.
Professional Experience
I. Project Experience – 5 years Research Associate (January, 2011 onwards), Senior Project officer (June, 2007 – February, 2010) and Junior Project Officer (June, 2006 – May, 2007) under Sponsored Research and Consultancy (SRIC), IIT Kharagpur.
Experience:
• Signal conditioning ASIC for MEMS Capacitive Accelerometer.
• Integration of MEMS with the designed ASIC and a commercially available IC MS3110 on PCB, hybrid integration ‐ ASIC and MEMS dies in a single package through wire bonding, static testing through electrostatic actuation and dynamic testing though vibrating shaker.
II. Work Experience – 3 years “Research and Development cum Service Engineer” in Life Guards Medical Devices Pvt. Ltd. (August, 2000 – November, 2003).
Experience: Implementation of various electronic circuits for artificial respirator and development of electrically operated microprocessor based ICU respirator.
Publications:
Journal
1. Sougata Kumar Kar and Siddhartha Sen, “Tunable Square‐Wave Generator for Integrated Sensor Applications”, IEEE Transactions on Instrumentation and Measurement, vol. 60, no.
10, pp. 3369‐3375, Oct. 2011.
2. Sougata Kumar Kar and Siddhartha Sen, “A Highly Linear Transconductance Amplifier in 180nm CMOS Process Technology”, Analog Integrated Circuits and Signal Processing, vol. 72, no. 1, pp. 163‐171, July, 2012.
Copyright
IIT Kharagpur
3. Sougata Kar, K. B. M. Swamy, B. Mukherjee and S. Sen, “Testing of MEMS Capacitive Accelerometer Structure Through Electro‐static Actuation”, Microsystem Technologies, Springer, vol. 19, no. 1, pp. 79‐87, January, 2013.
4. Sougata Kar and S. Sen, “Linearity Improvement of Source Degenerated Transconductance Amplifiers”, Analog Integrated Circuits and Signal Processing, Springer, vol. 74, no. 2, pp.
399‐407, February, 2013.
Conference
1. Dushyant Juneja, Sougata Kar, P. Chatterjee, and S. Sen, “SOI MEMS Based Over‐Sampling Accelerometer Design with ΔΣ Output”, VDAT‐2012, BESUS, Kolkata, July 1‐4, 2012.
2. Sougata Kumar Kar, K. B. M. Swamy, Banibrata Mukherjee and S. Sen, “Design and Testing of Signal Conditioning ASIC for MEMS Capacitive Sensor Applications”, ISSS, IISc‐Bangalore, January 5‐7, 2012.
3. K. B. M. Swamy, Banibrata Mukherjee, Sougata Kumar Kar and S. Sen, “Design and Fabrication of Planner SOI‐MEMS Accelerometer”, ISSS, IISc‐Bangalore, January 5‐7, 2012.
4. Banibrata Mukherjee, Sougata Kar, K.B.M. Swamy and S. Sen, “Performance Evaluation of MEMS based Capacitive Accelerometer Using Parameter Extraction”, Poster presentation, NCSA2011, National Conference on Sensor and Actuator: Science to Technology, CGCRI‐
Kolkata, March 11‐12, 2011.
5. Banibrata Mukherjee, K.B.M. Swamy, Sougata Kar and S. Sen, “Effect of Voltage Induced Electrostatic Forces on MEMS Capacitive Accelerometer”, Techsym2011, IEEE Students’
Technology Symposium, IIT Kharagpur, January 14‐16, 2011.
6. Banibrata Mukherjee, Sougata Kar, K.B.M. Swamy and S. Sen, “Modeling and Analysis of MEMS Capacitive Accelerometer”, NATCONIC2011, National Conference on Instrumentation and Control, Kolkata, January 6‐7, 2011.
7. K.B.M. Swamy, T.P. Singh, Sougata Kar and S. Sen, “Design, Fabrication and Testing of Comb type Capacitive Acceleration Sensor”, National Conference on MEMS, Smart Structures and Materials, ISSS – 2009, CGCRI‐Kolkata, October 14‐16, 2009.
8. S. Pandit, Sougata kar, C. Mandal and A. Patra, “High Level Synthesis of Higher order Continuous Time State Variable Filters with Minimum Sensitivity and Hardware Count”, DATE2006, Munich, March 6‐10, 2006.
Skill Sets
1. Hardware Language and Design Tools: Cadence for analog circuit Design, Simulation and Layout (Schematic Composer, Analog Design Environment and Virtuoso Layout Editor), MatLab, 8085 assembly language.
2. Board Design and development: Schematic & layout designs (OrCAD).
References
1. Prof. Siddhartha Sen, Dept. of Electrical Engg., IIT, Kharagpur.
Email: [email protected], Ph.: +91‐9434039856 2. Prof. Amit Patra, Dept. of Electrical Engg., IIT, Kharagpur.
Email: [email protected], Ph.: +91‐3222‐283070 3. Prof. T. K. Bhattacharyya, Dept. of E & ECE, IIT, Kharagpur.
Email: [email protected], Ph.: +91‐3222 ‐ 283554
Copyright
IIT Kharagpur
Annexure
I. PhD Research Operational Transconductance Amplifiers (OTA) are the basic building blocks in many analog circuits like continuous time filters, data converters and variable gain amplifiers. In a simple differential pair balanced OTA the even order harmonics are not dominant because of its differential nature but the odd harmonics contribute significant amount of distortion in the output current. The most popular linearization techniques include source degeneration, cross coupled differential pairs and adaptive biasing. I have proposed a highly linear OTA which combines the techniques of signal attenuation and resistive source degeneration, attenuated resistor de‐generated differential pair (ARDP). In this respect it has been shown that the mobility degradation effect helps to increase the linear range by partial cancellation of distortion component. The linear OTA is designed, simulated and fabricated in UMC 180nm CMOS process technology with 1.8V power supply.
Measured results show that third order inter‐modulation distortion (IM3) of linear OTA is less than ‐60dB for 500mVpp differential input signal at 5MHz signal frequency while for 2% trans‐conductance variation the linear range is about 1.2Vpp. The input referred noise of the OTA is 30nV/√Hz at 5MHz. The linear OTA achieves 69dB SNR for 500mVpp input signal. The quiescent power consumption is only 0.45mW.
A Gm‐C based continuous‐time tunable third order low‐pass filter based on the ladder structure using this linear OTA has also been designed, fabricated and tested. The cut‐off frequency of the filter is tunable from 300KHz to 1.7MHz. The measured IM3 of filter is less than ‐52dB for 500mVpp differential input signal at 600KHz signal frequency. The filter achieves 54dB SNR for 500mVpp differential input. The filter consumes only 3.2mW of quiescent power.
The linear OTA is also used to implement a completely OTA based square‐wave and clock generator with independent control over amplitude and frequency for integrated sensor applications. Two out of phase square‐waves along with rail to rail clocks are generated by this generator. Both amplitude and frequency of the waveform generator can be controlled independently by tuning the bias currents of the tuning OTAs. The complete circuit is fabricated in UMC 0.18μm CMOS process technology. The measured results show wide sweep capability of amplitude from 280mV pp to 1V pp and frequency from 120kHz to 900kHz approximately with good linearity. This generator is targeted for integrated capacitive and resistive sensors and other instrumentation applications.
A signal conditioning ASIC is also designed, fabricated and tested for a MEMS based capacitive accelerometer within the scope of a project work as mentioned below.
II. Project Experience Research Associate (January, 2011 onwards), Senior Project officer (June, 2007 – December, 2010) and Junior Project Officer (June, 2006 – May, 2007) under Sponsored Research and Consultancy (SRIC), IIT Kharagpur.
I am working in a project for development of “MEMS based Capacitive Accelerometer”, sponsored by Govt. of India, since June, 2006. We have designed, fabricated and tested a MEMS based capacitive accelerometer system for automotive and space applications. I am
Copyright
IIT Kharagpur
working mainly on the signal conditioning ASIC, integration of MEMS and ASIC and testing of the complete integrated system. The comb type MEMS structure has been fabricated from MEMSCAP and the ASIC using UMC 0.18µm process. The MEMS structures are packaged in PGA packages. The MEMS PGA package and the signal conditioning circuit have been integrated on a PCB. The complete system is tested through both electrostatic actuation by applying actuation signal in the actuation fingers and dynamic testing by a vibrating shaker.
Theoretical analysis has been carried out for various actuation conditions. We have observed the phenomenon of amplitude dipping and frequency doubling which perfectly matches with the theoretical analysis. This electrostatic testing confirms the proper working of the complete integrated system. Then the complete system is mounted on a vibrating shaker and dynamic testing is carried out with desired results. Next, we tried a second option of hybrid integration in which the MEMS and ASIC dies are placed side by side in a single package and integrated through wire bonding. We are not fully successful till now, we are trying to solve the issues related to hybrid integration as we believe that this hybrid integration should give better result than the first method of integration. Currently we have submitted an improved signal conditioning circuit based on switched capacitor based charge amplifier configuration with sigma‐delta modulator for fabrication.
III. Work Experience Worked as “Research and Development cum Service Engineer” in Life Guards Medical Devices Pvt. Ltd.
Period: Since August, 2000 – November, 2003
Technical Assignments undertaken: Associated with the design and implementation of different electronic circuits with discrete components like circuit for instrument failure, patient disconnection, respiratory rate display etc. of a pneumatically operated artificial respirator and servicing of the respirator. The next assignment was to develop an electrically operated respirator which can be used in ICU with a patient recovery facility. It was a microprocessor controlled respirator with digital display and control of tidal volume, flow rate, respiratory rate etc. along with fully automatic patient recovery process.
IV. Achievements
1. Best Paper award for the paper entitled “Effect of Voltage Induced Electrostatic Forces on MEMS Capacitive Accelerometer”, Techsym2011, IEEE Students’ Technology Symposium, IIT Kharagpur, January 14‐16, 2011.
2. Invited Talk on “Critical Issues in the Development of MEMS based Capacitive Accelerometer”, National Workshop on Critical Issues in Sensor Development‐Materials to Packaging & Instrumentation, BESUS, Shibpur, Kolkata, Jan. 3‐10, 2007.
3. Qualified all India Graduate Aptitude Test (GATE) in engineering in 2004.
V. Extracurricular Activities
1. Captain of the cricket team, 1999, Department of IE, HIT, Haldia.
2. Captain of the football team in inter‐hall football, 2009 of Vikram Sarabhai Residential Complex (VSRC), IIT Kharagpur.