The area of my research is design and development of low power and low noise analog signal
conditioning integrated circuits with focus towards their application in biomedical systems. One
aspect of my research is the design and development of ultra-low noise instrumentation amplifier
(ULN-INA) as plug-in solution that can be used to record various bio-potentials as well as
from bio-sensors. This fabricated INA has achieved one of the lowest Noise Efficiency Factor, as
reported in literature till date. We have successfully demonstrated a complete ExG (ECG, EMG,
EOG) measurement system built using our CMOS custom designed application specific integrated
(ASIC). Further, we have also developed a programmable gain and bandwidth INA (PGB-INA) that is
highly versatile and can be used to acquire a variety of bio-potentials and sensor signals.
The other aspect of my work is the development of an ultra-low power (< 200 μW) pulse
oximeter (PO) ASIC suitable for application in wearable platforms with tolerance to the
unavoidable finger movements. To demonstrate the functionality of the custom designed PO
ASIC, we have made a fully functional pulse oximeter prototype, OxiSense. By virtue of its
novel signal processing algorithm, the PPGs acquired by OxiSense is relatively immune to
minor motion artefacts like shivering and finger movements which are unavoidable in many
This research was funded by Ministry of Electronics and Information
Technology(MeitY), Govt. of India and was
out in the Department of Electrical Engineering, IIT Bombay with my research guide Prof.
Maryam Shojaei Baghini. All the designs are silicon proven which have been
in UMC 180nm mixed-mode CMOS technology by the Europractise-IC fabrication service
(mini@sic) of IMEC.
- D.M.Das, A. Vidwans, A. Srivastava, M. Ahmad, S. Vaishnav, S. Dewan and M.
Shojaei Baghini, "Design and Development of an IoT Enabled Wearable ExG Measuring
with a Novel Signal Processing Algorithm for ECG", IET Circuits, Devices and Systems
Journal, May 2019.
- D.M.Das, A. Gupta, A. Vidwans, A. Srivastava, M. Ahmad, A. Shelke, S. Kale,
Ananthapadmanabhan, D. K. Sharma and M. Shojaei Baghini, "A Pulse Oximeter System,
OxiSense, with Embedded Signal Processing using an Ultra-low Power ASIC
for Testability", Elsevier Microelectronics Journal, December 2017.
- D.M.Das, A.Srivastava, Ananthapadmanabhan J., M.Ahmad and M.Shojaei Baghini,
novel low-noise fully differential CMOS instrumentation amplifier with 1.88 noise
efficiency factor for biomedical and sensor applications", Elsevier Microelectronics
Journal, July 2016. (One of the most downloaded papers in 2016)
- A. Srivastava, D.M.Das, P. Mathur, D. K. Sharma and M. Shojaei Baghini,
nJ/bit OOK Transmitter for Wearable and Implantable Devices in 400 MHz MedRadio
IEEE Microwave and Wireless Components Letters, 2018.
- A. Srivastava, N. Sankar K., B. Chatterjee, D.M.Das, M. Ahmad, Rakesh K. K.,
Saraf, J. Ananthapadmanabhan, D. K. Sharma, and M. Shojaei Baghini, "Bio-WiTel: A
Power Integrated Wireless Telemetry System for Healthcare Applications in 401-406
Band of MedRadio Spectrum", IEEE Journal of Biomedical and Health
- B. Chatterjee, N. Modak, Anvesha A, D. Mistry, D.M.Das and M. Shojaei
"A sub-1V, 120 nW, PVT-variation Tolerant, Tunable and Scalable Voltage Reference
60 dB PSNA", IEEE Transactions on Nanotechnology, January 2017.
- D.M.Das, A. Srivastava, A. Gupta, K. Barot and M. Shojaei Baghini, "A
Noise-power-area Optimized Novel Programmable Gain and Bandwidth Instrumentation
Amplifier for Biomedical Applications", Proc. of IEEE ISCAS, 2017, USA.
- D.M.Das, J. Anantha and M.Shojaei Baghini, "Design Considerations for
Low- Power Current Mode Instrumentation Amplifier for Biomedical Data Acquisition
Systems", Proc. of IEEE ICECS, 2014, France.
- S. Boyapati, D.M.Das, M. Shojaei Baghini and J. M. Redoute, "A Balanced CMOS
OpAmp with High EMI Immunity", Proc. of IEEE EMC Europe, 2014, Sweden.
- A. Srivastava, N. Sankar, D.M.Das and M. Shojaei Baghini, "LNA-LO Co-Design
Considerations For Low Intermediate Frequency Receivers In 401-406 MHz MedRadio
For Healthcare Applications", International Conf. on VLSI Design, 2017, India.
- A. Srivastava, D.M.Das, Vignesh M S, Bharadwaj K., Sourya Dewan and Maryam
Shojaei Baghini, "Bio-Telemetry And Bio-Instrumentation Technologies For Health Care
Monitoring Systems", IEEE Humanitarian Technology Conf. (HTC), 2016, India.
- A.Srivastava, D.M.Das, D.K.Sharma and M.Shojaei Baghini, "SAW Resonator
Oscillator Based Injection Locked OOK Transmitter for MedRadio Spectrum" in IEEE
Canada, Jun. 2016.
- P.Kimtee, D.M.Das and M.Shojaei Baghini, "A Mismatch Insensitive
Discrete Time Biosignal Conditioning Circuit in 180 nm MM CMOS Technology" in IEEE
India, May 2016.
- A. Srivastava, N. Sankar K, Rakesh K K, B. Chatterjee, D.M.Das and M.
Baghini, "Design And Measurement Techniques For A Low Noise Amplifier In A Receiver
Chain For MedRadio Spectrum" in IEEE VDAT, India, May 2016.
Chip micrographs and layouts:
- Inventor in a patent filed on Ultra low noise instrumentation amplifier. Patent
- Co-inventor in a patent filed on handheld pulse oximeter recording and analysis
- Co-inventor in a patent filed on a novel method for comparator input offset
compensation. Patent pending.
- Co-inventor in a patent filed on a design method for low-power low-noise
signal conditioning circuit with extracted noise and mis-match parameters. Patent
- Co-inventor in a patent filed on voltage mode log domain low-pass filter. Patent
- Co-inventor in a patent filed on SAW resonator oscillator based injection locked
transmitter for health care applications in MedRadio spectrum (401-406 MHz). Patent
- Co-inventor in a patent filed on design considerations for transmitter and receiver
personal health care applications. Patent pending.