Cypress's Maker of the Month: Srinivas Mandalika | Cypress Semiconductor
Cypress's Maker of the Month: Srinivas Mandalika
The Maker of the Month series recognizes unique projects created by the maker community. At Cypress, we are committed to helping our customers (international OEMs and makers alike) bring their innovations to life with our easy-to-use software tools and programmable solutions. For more information about Cypress’s maker community involvement, check out the rest of our Maker of the Month series and our efforts to empower up-and-coming engineers via the Cypress University Alliance (CUA).
Read the Q&A with Cypress’s Maker of the Month, Srinivas Mandalika. Srinivas is a professor at BITS Pilani, India and has created an acute respiratory infection monitor based on Cypress’s PSoC 3.
Please provide some background about yourself and your work at BITS Pilani Hyderabad Campus.
I am currently a professor of electrical engineering at BITS Pilani, Hyderabad Campus, India. My research is centered around VLSI arithmetic circuits, data converters and ICT for affordable healthcare, areas in which I am currently supervising 15 PhD students. Along with my student teams, I have designed and built several portable medical devices that take advantage of smartphone technology. I was also a recipient of the Microsoft Research Digital Inclusion Award in 2006.
Realizing the importance of working with doctors, hospitals and the communities, I currently collaborate with MediCiti Institute of Medical Sciences (MIMS) in Hyderabad, whose research Arm Science Health Allied Research Education (SHARE) India focuses on rural healthcare. My work has been supported by Microsoft Research, the Indian Council of Medical Research (ICMR) and Cypress Semiconductor.
Tell us about your respiratory distress monitor for infants and what Cypress technology is being used in the project.
The Acute Respiratory Infection (ARI) monitor is a portable diagnostic device that detects respiratory distress in children below the age of five. The monitor measures pulse rate, body temperature, breathing rate and percentage of oxygen saturation in the blood (SPO2). Elevated levels of these parameters beyond certain thresholds indicate respiratory distress, a severe form of which is pneumonia.
My team also developed a smartphone application which communicates with the ARI monitor via wired (USB) or wireless (Bluetooth) connection to display and store the data. The application is capable of sending an alert to a doctor in severe cases of respiratory distress.
The ARI monitor is built around Cypress’s PSoC 3 controller that has an analog front-end for initial signal conditioning. It is further used for simple digital signal processing and for controlling and computational functions. The pulse Oximeter (SPO2) part of the device requires driving of two LEDs (Red and Infrared) in a time-multiplexed fashion with photo detectors output de-multiplexed to separate two signals corresponding to individual sources. The PWM of PSoC 3 is used for generating the driving signals for each LED and also signals are de-multiplexed using the same PWM output as an interrupt source, thus minimizing the complexity of the driving circuitry leading to minimization of hardware footprint.
The ARI monitor will be used by trained village health workers in about 40 villages in the outskirts of Hyderabad under the supervision of SHARE India.
How did you come up with the idea for the ARI monitor?
The idea came from one of the co-founders of the SHARE India foundation, Professor P.S. Reddy of UPMC, Pittsburgh. He and his colleagues Dr. Enakshi Ganguly and Dr. Pavan Sharma, both of whom are doctors of community medicine at the MediCiti Institute of Medical Sciences, felt the need to address the large infant mortality rate in India—30% of which is due to acute respiratory problems, including pneumonia. They discussed the problem with us and provided their expectations of a monitor to address the same. I, along with my PhD student Avinash Vaidya, then explored several alternative hardware designs before deciding on PSoC 3.
How did Cypress’s technology help execute your projects, and what are the benefits you’ve seen with using these technologies?
The analog signal processing and computations in the ARI monitor are carried out using Cypress PSoC 3, along with a minimal external analog front-end. PSoC 3’s analog capability and programmability gave a unique combination that helped in rapid development of the device.
The four parameters that are measured by the ARI monitor are derived from two signal inputs viz. Photoplethysmograph of the pulse Oximeter and the temperature sensor. Due to the nature of the signals, each signal had to be digitized with different ADC configurations, which are possible in PSoC 3 with a single ADC. The Delta-Sigma Analog-to-Digital Converter of PSoC 3 is reconfigured to eliminate the usage of an additional ADC.
Further, the PSoC Creator development tool provided a feature-rich, easy-to-use environment, facilitating the rapid development of the device. The development community of PSoC 3 also provided a large number of tutorials, application notes, videos, etc., that also helped us. The PSoC Creator code optimization option helped reduce the required memory size and made it possible to implement a simple DSP in a memory limited environment of PSoC 3.
Are you working on any other projects that use Cypress’s technology?
Our earlier work using Cypress technology included a design of a 3-lead portable ECG recorder and a BMI (Body Mass Index) monitor to detect malnourishment/obesity in children. Both prototypes are designed around PSoC 3.
We are currently working on the next version of the ARI monitor that would be based on PSoC 5.
We have had a great experience working with Cypress’s technology. The presence of analog hardware as well as the programmability of analog/digital hardware help in rapid prototyping and proof of concept. The folks at Cypress are also very helpful and generous in giving away the hardware and the tools for our project.
For questions or more information, you can reach out to Srinivas Mandalika here.
Thanks again to Srinivas for participating in our Maker of the Month program. If you would like to be considered for our next Maker of the Month profile, please email us and share a brief description of what project(s) you have made using Cypress’s technology.