This year at ISSCC, we will feature four papers – congratulations to the students who worked hard to make these exciting chips work! More details will be made available when the advanced program becomes available.
In addition, Prof. Mercier servers on the Executive Committee of ISSCC as the demo chair – please be sure to stop by the demo sessions on Monday and Tuesday evenings to check out exciting live chip demonstrations.
Preventing the next pandemic begins before diseases emerge. This “pre-emergence” phase is the focus of a new Center—funded by the U.S. National Science Foundation (NSF)—that is dedicated to developing cutting-edge technologies for disease investigations and pandemic research.
Dubbed the U.S. National Science Foundation Center for Pandemic Insights (NSF CPI), the Center is supported with $18 million over seven years through NSF’s Predictive Intelligence for Pandemic Prevention (PIPP) program. The Center, led by the University of California, Davis, involves 10 partnering institutions from across the United States, including the University of California San Diego. One goal of the Center is to advance detection of emerging infectious diseases at their origin—before they spill over from wildlife to humans—by creating sophisticated sensor systems that monitor disease activity in natural settings.
“This Center is a moonshot for being able to transform how we do investigations into the pre-emergence phase for pandemics,” said Center lead Christine K. Johnson, a professor of epidemiology and ecosystem health in the UC Davis School of Veterinary Medicine and director of the EpiCenter for Disease Dynamics in its One Health Institute. “We’ll be able to optimize cutting-edge technology that’s already being applied in areas of human health, engineering and agriculture and bring them into this important space to help with wildlife and pandemic threats.”
Most pandemics are caused by emerging infectious diseases that originate in wildlife and are detected only after causing outbreaks in humans. The complex nature of infectious diseases limits the ability of scientists to conduct targeted surveillance and gather data at the speed or scale needed to detect pandemic threats.
“Our goal is to develop the tools that will allow us to see and understand these threats in their natural cycles,” said Patrick Mercier, a professor in the Department of Electrical and Computer Engineering at the UC San Diego Jacobs School of Engineering and co-investigator of the Center. “By doing so, we aim to shift the paradigm from reactive crisis management to proactive prevention.”
Read more about this exciting venture HERE.
Congratulations to Prof. Mercier for becoming the new Vice Chair of the Electrical and Computer Engineering Department at UCSD!
Scientists at the University of California San Diego and CEA-Leti have developed a ground-breaking piezoelectric-based DC-DC converter that unifies all power switches onto a single chip to increase power density. This new power topology, which extends beyond existing topologies, blends the advantages of piezoelectric converters with capacitive-based DC-DC converters.
The power converters the team developed are much smaller than the huge, bulky inductors currently used for this role. The devices could eventually be used for any type of DC-DC conversation, in everything from smart phones, to computers, to server farms and AR/VR headsets.
The results were presented in the paper, “An Integrated Dual-side Series/Parallel Piezoelectric Resonator-based 20-to-2.2V DC-DC Converter Achieving a 310% Loss Reduction”, Feb. 20 at ISSCC 2024 in San Francisco.
“The Dual-side Series/Parallel Piezoelectric Resonator (DSPPR) is the first IC used for PR-based power conversion, and achieves up to 310% loss reduction over prior-art published and co-designed discrete designs for VCRs<0.125,” the paper reports.
“This innovative approach enhances performance, especially at low voltage conversion ratios—an area where prior works struggled to sustain both high efficiency and optimal utilization of piezoelectric materials,” said Patrick Mercier, a professor in the Department of Electrical and Computer Engineering at UC San Diego and a senior author of the paper.
Read more about this work HERE.
Congratulations, Prof. Mercier! 
A pair of earbuds can be turned into a tool to record the electrical activity of the brain as well as levels of lactate in the body with the addition of two flexible sensors screen-printed onto a stamp-like flexible surface.
The sensors can communicate with the earbuds, which then wirelessly transmit the data gathered for visualization and further analysis, either on a smartphone or a laptop. The data can be used for long-term health monitoring and to detect long-term neuro-degenerative conditions.
The sensors, developed by a multidisciplinary research team of engineers at the University of California San Diego, are a lot less cumbersome than state of the art devices currently used to sense the brain’s electrical activity and the body’s sweat secretions. They can be used in the real world during exercise, the researchers showed.
While in-ear sensing of several physiological parameters is not new, integrating sensing of brain and body signals in a single platform is. The breakthrough was made possible by the combined expertise of biomedical, chemical, electrical, and nano-engineers.
Data from an electroencephalogram (EEG), which measures electrical activity in the brain, and sweat lactate, an organic acid the body produces during exercise and normal metabolic activity, can be combined for a variety of purposes. For example, they can be used to diagnose different types of seizures, including epileptic seizures. They can also be used for monitoring effort during physical exercise and monitoring levels of stress and focus.
The researchers validated the data collected during this proof-of-concept study against data obtained from commercially available dry contact EEG headsets and lactate-containing blood samples. The data the flexible sensors collected were just as effective.
The team describes their work in an article appearing on the cover of the October 2023 issue of Nature Biomedical Engineering.
The researchers foresee a future, in which neuroimaging and health monitoring systems work with wearable sensors and mobile devices, such as phones, earbuds, watches, and more to track brain activity and levels of many health-related metabolites throughout the day. This would allow users to enhance brain and body capabilities. The team also envisages a future in which the capabilities of existing wearable audio devices, such as earbuds, can be considerably expanded to gather a much wider range of data.
“Being able to measure the dynamics of both brain cognitive activity and body metabolic state in one in-ear integrated device that doesn’t intrude on the comfort and mobility of the user opens up tremendous opportunities for advancing health and wellness of people of all ages, anytime and anywhere,” said Gert Cauwenberghs, a professor in the Shu Chien Gene Lay Department of Bioengineering at UC San Diego.
The team felt that the ubiquitous wearing of earbuds translated to an untapped potential for gathering brain and body signals conveniently, both for wellness and health.
“Earbuds have been around for decades, and in many ways were one of the first wearable devices on the market,” said Patrick Mercier, a professor in the UC San Diego Department of Electrical and Computer Engineering. “This research takes important first steps to show that impactful data can be measured from the human body simply by augmenting the capabilities of earbuds that people already use on a daily basis. Since there are no major frictions to using this technology, we anticipate eventual wide scale adoption.”
The ear has sweat glands and is close to the brain, said Yuchen Xu, co-first author of the paper, and a postdoctoral researcher in Cauwenberghs’s lab. “It’s a natural entry point–people are used to wearing earbuds,” he said.
Imagine you can open your fridge, open an app on your phone and immediately know which items are expiring within a few days. This is one of the applications that a new technology developed by engineers at the University of California San Diego would enable.
The technology combines a chip integrated into product packaging and a software update on your phone. The phone becomes capable of identifying objects based on signals the chip emits from specific frequencies, in this case Bluetooth or WiFi. In an industrial setting, a smartphone equipped with the software update could be used as an RFID reader.
The work harnesses breakthroughs in backscatter communication, which uses signals already generated by your smartphone and re-directs them back in a format your phone can understand. Effectively, this technique uses 1000 less power than state of the art to generate WiFi signals These advances have enabled very low-power communication between components of the Internet of Things and hardware such as WiFi or Bluetooth transceivers, for applications such as on-body sensors or asset trackers.
The custom chip, which is roughly the size of a grain of sand and costs only a few pennies to manufacture, needs so little power that it can be entirely powered by LTE signals, a technique called RF energy harvesting. The chip turns Bluetooth transmissions into WiFi signals, which can in turn be detected by a smartphone with that specific software update.
The team will present their work at the IEEE International Solid-State Circuits Conference in San Francisco on Feb. 20, 2023. Read more about this HERE.
We are pleased to announce the Energy Efficient Microsystems Lab will help present two papers at ISSCC 2023. One will be on a vertically-integrated power delivery system in collaboration with Prof. Hanh-Phuc Le’s group, and the other will be on a single-mobile-device interrogator that enables LTE energy harvesting and BLE-to-WiFi backscatter in collaboration with Prof. Dinesh Bharadia’s team. More details available at ISSCC in February! This brings the EEMS total ISSCC paper count over the last seven years to 19 (with 25 total papers over Prof. Mercier’s career).
Also, Prof. Mercier is chairing the two demo sessions at ISSCC this year, and both papers will be participating. Please be sure to attend if you want to see both of these systems working, along with many other exciting demos!
UC San Diego has created an experimental “smart pill” that continuously monitors the inside of the small intestine, work that could lead to better ways to spot and treat gastro-intestinal disorders, including inflammatory bowel disease and diabetes.
The inch-long, wireless biosensor was placed in pigs and successfully took real-time glucose readings for periods ranging from two to five hours, according to a paper UCSD just published in the journal Nature Communications. The data was relayed by the pill’s tiny antenna.
Researchers used pigs because their GI tract is similar to the one in humans.
The proof-of-concept work was conducted by engineers at UCSD’s Center for Wearable Sensors, which broadly works on health-related devices.
The researchers will now try to find ways to make the smart pill smaller so that it can be easily swallowed by humans. They’ll also make it capable of taking a greater variety of readings.
The sensor is meant to be an alternative to the endoscope — a long, thin tube with a camera that is typically threaded through a person’s mouth and throat, down into their digestive tract. It provides a limited, short-term look at a person’s condition.
“Right now, if you have a stomach problem (doctors) can take an X-ray but that’s not going to tell you much,” said Patrick Mercier, co-director of the Center for Wearable Sensors. “And they can do an ultrasound.
“But you can’t access the gut without doing an endoscopy, which means you have to put the patient under. They stick a tube all the way down. It’s very painful.
“This technology offers a really interesting new avenue to access this (relatively) inaccessible piece of the human body. We could adapt it to measure all sorts of things. If you had acid reflux we could measure the acid in your stomach in real-time.”
Read more about this in the San Diego Union Tribune, on KPBS, or UCSD News. The Nature Communications paper can be found as an open access article HERE.
UC San Diego is about to open a huge, cathedral-like engineering center that will exponentially expand the school’s efforts to do everything from turn plant viruses into human vaccines to program self-driving cars to safely navigate through thick fog.
Franklin Antonio Hall, which cost $180 million to build, will feature 13 “collaboratories,” glassy open spaces meant to maximize the ability of faculty and students from different disciplines to work together, possibly shoulder-to-shoulder with industry engineers.
Prof. Mercier’s Energy Efficient Microsystems Group will be moving into this new building as part of the UCSD Center for Wearable Sensors and Center for Wireless Communications. Read more about this in the San Diego Union Tribune article HERE.
Prof. Mercier discussed his research in collaboration with Dinesh Bharadia about low-power WiFi backscatter communication at the 2022 UCSD Center for Wireless Communications Semi Annual Research Review, with his talk available now on YouTube:
Imagine being able to measure your blood sugar levels, know if you’ve had too much to drink, and track your muscle fatigue during a workout, all in one small device worn on your skin. Engineers at the University of California San Diego have developed a prototype of such a wearable that can continuously monitor several health stats—glucose, alcohol, and lactate levels—simultaneously in real-time.
The device is about the size of a stack of six quarters. It is applied to the skin through a Velcro-like patch of microscopic needles, or microneedles, that are each about one-fifth the width of a human hair. Wearing the device is not painful—the microneedles barely penetrate the surface of the skin to sense biomolecules in interstitial fluid, which is the fluid surrounding the cells beneath the skin. The device can be worn on the upper arm and sends data wirelessly to a custom smartphone app.
Researchers at the UC San Diego Center for Wearable Sensors describe their device in a paper published May 9 in Nature Biomedical Engineering.
Read more at the press release HERE, or the actual paper HERE.
The EEMS lab, in collaboration with Prof. Dinesh Bharadia’s lab, are pleased to announce that they will be presenting a paper at ISSCC 2022 entitled “A WiFi and Bluetooth Backscattering Combo Chip Featuring Beam Steering via a Fully-Reflective Phased-Controlled Multi-Antenna Termination Technique Enabling Operation Over 56 Meters”. Along with co-authors Shih-Kai Kuo and Manideep Dunna, they will show how beamsteering can be enabled in a WiFi-compatible backscatter system that consumes multiple orders of magnitude lower power than conventional approaches. They will also demonstrate that the chip can also backscatter BLE data at ~100X lower power than a Bluetooth Low Energy transmitter.
Prof. Mercier will also be busy in other areas of ISSCC. He is the lead organizer of the Forum entitled “Chip Design for Low-Power, Robust, and Secure IoT Devices”, featuring presentations by authors from Qualcomm, ETH Zurich, Nordic Semiconductor, Broadcom, NXP, Renesas, Nanyang Technological University, and Texas Instruments on various IoT-related topics. He is also a co-organizer of a panel session entitled “The Next Trillion-Dollar Market”, featuring opinions on what this might be from by panelists from MediaTek, UC Berkeley, Sony, Trilogy Networks, NVIDIA, and IBM.
Overall, this should be a very exciting year at ISSCC 2022!
POSITION DESCRIPTION
The Electrical and Computer Engineering Department, at the University of California, San Diego, in support of the Jacobs School of Engineering multidisciplinary research in the Center for Wearable Sensors is conducting an open search for Postdoctoral Scholars in various academic disciplines, with a focus on those with a background in biomedical engineering with expertise in one or more of physiology, electronics, material science, embedded system design, programming, bio signal processing, and project management.
The University of California employs about 5,963 postdoctoral scholars (approx. 1,200 at UCSD) who contribute to the academic community by enhancing the research and education programs of the university. The postdoctoral experience emphasizes scholarship and continued research training. UC’s postdoctoral scholars bring expertise and creativity that enrich the research environment for all members of the UC community, including graduate and undergraduate students. Appointment durations vary depending on the length of the research project and the availability of funding. The total duration of an individual’s postdoctoral service may not exceed five years, including postdoctoral service at other institutions. The International Union, United Automobile, Aerospace and Agricultural Implement Workers of America (UAW) is the exclusive representative of the postdoctoral scholars.
Required Qualification:
Doctorate degree or its equivalent in the project area. The appointment is dependent on academic experience, scholarly achievements, skills and knowledge, and the needs of the center.
Preferred Qualification:
The candidate will be responsible for working with and managing projects funded and guided by a corporate sponsor in the areas of wearable devices for precision athletics, nutrition and/or general population health. The candidate will ideally have a background in physiology and/or wearable devices, with a specialization in one or more of the following fields: electronics, material science, embedded systems, firmware development, and/or bio signal processing. The candidate should have good project management skills, be able to lead project meetings, cross disciplinary boundaries, clearly document work progress and articulate such progress to academic and industry audiences, and be able to prepare high quality academic manuscripts and literature review white papers. The candidate will liaise with the corporate sponsor and their team of academics to apply the learnings and projects to a commercial setting. The candidate should share a commitment to mentoring and research training service to build an equitable and diverse scholarly environment.
Review of applications will commence immediately and will be ongoing. Salary is commensurate with qualifications and based on published University of California pay scales. Applications (CV, Research Statement, and Cover letter, at minimum) must be submitted via email to ece-apply@eng.ucsd.edu.
The Office of Research Affairs at UC San Diego is committed to academic excellence and diversity within the academic, staff, and student body. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, disability, or status as a protected veteran.
APPLICATION REQUIREMENTS
Document requirements:
Curriculum Vitae – Your most recently updated C.V.
Cover Letter
Statement of Research, Interests and Goals – Applicants should summarize their past or potential contributions to the Center for Wearable Sensor’s needs as outlined above.
Misc / Additional (Optional)
Despite ties to the fashion sector, wearables may evolve to the point where consumers may not even see the technology they’re wearing. Read more in this nice article, which extensively quotes Prof. Mercier, HERE.
A nice article about the activities in the Center for Wearable Sensors appeared in the Triton Magazine, including interview excerpts with Prof. Mercier and colleagues. Read more HERE.
We are very excited to announce we will be presenting FIVE papers at ISSCC 2021! This brings EEMS total ISSCC paper count over the last five years to 16 (five papers in 2021, one in 2020, four in 2019, three in 2018, and three in 2017), with 22 papers total in Prof. Mercier’s career. ISSCC 2021 will feature the following papers:
These are exciting developments, and we look forward to sharing these results in February 2021.
UC San Diego’s Center for Wearable Sensors, which is co-Directed by Prof. Mercier, normally has a public summit hosted once per year on UCSD campus. Due to the pandemic, we have decided to move this summit online, and are opening up registration to anyone – for free! The summit will discuss wearable flexible solar cell technology, ultra-low-power wireless communication techniques using Bluetooth Low-Energy and Wi-Fi backscatter, warfighter performance monitoring, machine learning for wearables and IoT, and microneedle array technology for lab-on-skin applications.
Please find the registration information and agenda below HERE.
Patrick Mercier and Joseph Wang’s work on biofuel cells and self-powered sensors is featured on the cover of the July 2020 issue of IEEE Spectrum. Check it out!
https://spectrum.ieee.org/semiconductors/devices/why-sweat-will-power-your-next-wearable