About

Yeonjin Kim has received international acclaim as a soloist, recitalist, and chamber musician. She has performed at major venues including the Kennedy Center, Konzerthaus Berlin, Berlin Philharmonie, Seoul Arts Center, and Suntory Hall, and as a soloist with orchestras in Cleveland, Ann Arbor, Colorado, Seoul, Tianjin, and Manila. Her concerts have been broadcast on television and radio across the United States, Korea, China, and Japan. She has been a top prizewinner in several international competitions, including the Sorantin International Competition, Dichler-Sato International Competition, Viva Hall Competition, and the Korea Philharmonic Orchestra Competition. Her solo recording of Max Reger’s Three Suites for Cello Solo has been praised for its depth and expressive power.

Research topics

• Computer Science
• Electrical engineering
• Physics
• Engineering
• Electronic engineering
• Acoustics
• Quantum mechanics
• Materials science
• Arithmetic
• Embedded system
• Optoelectronics
• Mechanical engineering
• Computer network
• Telecommunications
• Mathematics

Selected publications

• Low-Power Power Management Unit With Adaptive Dynamic Load Power Tracking for Millimeter-Scale Computing Systems

  IEEE Transactions on Power Electronics · 2025-09-01 · 2 citations

  article

  This paper proposes a Power Management Unit (PMU) for a millimeter-scale, multi-layer-stacked computing system, designed to efficiently manage significant load current variations between low-power sleep mode and high-performance active mode. The system ensures a reliable power supply across different chip layers, rapidly increasing output driving strength in response to active-mode requests from any layers. Additionally, the circuit adaptively manages the switching frequency of its power converters for dynamic frequency scaling, compensating for temperature changes by using an oscillator that replicates the processor's clock. The proposed design is fabricated using a 180 nm process and integrated with other chip layers in a millimeterscale system. The system's PMU eliminates voltage drop during transitions to active mode by utilizing a constant energy-per-cycle oscillator with a wide frequency range of 1.89 Hz to 104 MHz, along with a replica oscillator of the processor. It achieves over 50% power conversion efficiency across a load power range of 41 nW to 409 μW.

  PublisherDOI

• An Ultralow-Power Triaxial MEMS Accelerometer With High-Voltage Biasing and Electrostatic Mismatch Compensation

  IEEE Journal of Solid-State Circuits · 2024-01-15 · 2 citations

  articleOpen access

  This article presents a triaxial microelectromechanical system (MEMS) capacitive accelerometer using a high-voltage biasing technique to achieve high resolution with ultralow power. The accelerometer system generates a differential pair of high voltages to bias the MEMS structure, raising the MEMS signal substantially above the noise floor of the analog front-end (AFE) circuits. With the consequent increased signal-to-noise ratio (SNR), the proposed accelerometer system eliminates the need for a power-hungry low-noise amplifier (LNA) and signal chopping which significantly improves the power-noise tradeoff found in conventionally biased MEMS accelerometers. Moreover, by fine-tuning the bias voltages, the proposed method cancels the electrostatic mismatch in the MEMS due to process variation and ensures robust operation. The proposed accelerometer is composed of one integrated MEMS-CMOS chip and one CMOS-only chip. In postfabrication testing, it achieves a 121- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu$</tex-math> </inline-formula> g/ <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\surd$</tex-math> </inline-formula> Hz input-referred noise floor with <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\pm$</tex-math> </inline-formula> 1.5-g dynamic range, <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${&lt;}1$</tex-math> </inline-formula> % linearity error, and 184-nW per-axis power (including high-voltage bias generation). Compared to prior art, the design achieves a 10.3 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\times$</tex-math> </inline-formula> FoM improvement in both power and noise specifications.

  PublisherOA PDFDOI

• A Sub-mm³ Wireless Neural Stimulator IC for Visual Cortical Prosthesis With Optical Power Harvesting and 7.5-kb/s Data Telemetry

  IEEE Journal of Solid-State Circuits · 2024-01-30 · 11 citations

  articleOpen access

  This article proposes StiMote, an untethered, free-floating and individually addressable stimulator mote designed for visual cortex stimulation, aimed at vision restoration. The system is optically powered by a custom photovoltaic (PV) layer. In addition, the photodiode (PD) layer captures the light modulation and forwards it to the optical receiver (ORX) including a tranimpedance amplifier. Translated instructions can assign a unique slot, up to 1024 available, to each mote within the time-division multiple access (TDMA) framework. In this work, we propose an automatic charge balance (CB) technique that monitors the injected charge to balance in bi-phasic switched-capacitor stimulation (SCS). The chip was confirmed fully functional when operated completely wirelessly using harvested light. Measurement results revealed a power consumption of 4.48 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu $ </tex-math></inline-formula> W with a 7.5-kb/s optical downlink data rate, corresponding to continuous updates at 2.5 Hz of 1024 motes to their individual 3-b stimulation intensity levels. The dc–dc converter, responsible for providing high voltage for stimulation, demonstrated 4.3-V output voltage when unloaded, with a maximum efficiency of 67.4%. The proposed CB circuit exhibited linear controllability of stimulation charge up to 16 nC, with a charge imbalance of less than 0.2 nC. Furthermore, in vitro testing confirmed the absence of chemical reactions at electrodes, and in vivo experiments conducted on live rats verified the effectiveness of the stimulation through StiMote.

  PublisherOA PDFDOI

• A 5-mm², 4.7-<i>μ</i>W Convolutional Neural Network Layer Accelerator for Miniature Systems

  IEEE Transactions on Very Large Scale Integration (VLSI) Systems · 2023-10-23

  article

  This brief presents an energy-efficient accelerator for convolutional neural network (CNN) layer computations in a compact system. The accelerator replaces traditional data shift registers with a multiplexer-based barrel shifter, offering greater flexibility for supporting various models and reducing power consumption by 56.2% compared to flip-flop-based shifters. The prototype, fabricated using a 180-nm CMOS process, accelerates CIFAR-10 dataset CNN computations by 8.5 times compared to a system without the accelerator. It achieves this speedup while consuming only <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$4.7 ~\mu \text{W}$ </tex-math></inline-formula> of power and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$9.53 ~\mu \text{J}$ </tex-math></inline-formula> for each inference task.

  PublisherDOI

• A Wireless Neural Stimulator IC for Cortical Visual Prosthesis

  2023-06-11 · 5 citations

  articleOpen access

  ) optically powered mote for visual cortex stimulation to restore vision. Up to 1024 implanted motes can be individually addressed. The complete StiMote system was confirmed fully functional when optically powered and cortex stimulation was confirmed in-vivo with a live rat brain.

  PublisherOA PDFDOI

• A High-Voltage Generator and Multiplexer for Electrostatic Actuation in Programmable Matter

  IEEE Journal of Solid-State Circuits · 2022 · 14 citations

  • Computer Science
  • Electrical engineering
  • Computer Science

  Programmable matter (PM) consists of tiny, mm-scale quasi-spherical robots that can be combined and programmed to form any arbitrary 3-D shape autonomously. While PM enables instant structural visualization and opens up a host of industrial and artistic applications, it also raises significant challenges in micro-robot control, communication, and actuation that are difficult to support with existing system-on-chip (SoC) designs. This article presents a high-voltage-generation-and-multiplexer (HVGM) chip specially designed for electrostatic actuation of micro-robots for applications such as PM. The HVGM individually controls 12 pairs of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$+/-$ </tex-math></inline-formula> electrodes using a positive and negative charge pump and mux-structure, consuming only 286 nW power when switching a 10 pF electrode at 155 V/s, and producing a differential voltage of 103 V (29 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\times $ </tex-math></inline-formula> voltage gain from 3.6 V) in measurement. We also show a complete micro-system of stacked dies, measuring 3 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\times $ </tex-math></inline-formula> 1.4 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\times $ </tex-math></inline-formula> 1.1 mm, including the HVGM, a processor, radio, and harvester that achieves energy-autonomous operation, and can be integrated into a micro-robot “Catom” via a flexible PCB.

  PublisherDOI

• A 184nW, 121µg/√Hz Noise Floor Triaxial MEMS Accelerometer with Integrated CMOS Readout Circuit and Variation-Compensated High Voltage MEMS Biasing

  2022 IEEE Symposium on VLSI Technology and Circuits (VLSI Technology and Circuits) · 2022 · 9 citations

  • Computer Science
  • Electrical engineering
  • Electronic engineering

  We present a triaxial MEMS accelerometer readout circuit (RoC) with 40× signal gain using a high MEMS bias voltage, reducing power by eliminating the need for a chopped AFE chain. The proposed RoC achieves a 121µg/√Hz input referred noise and 1.5g dynamic range at 184nW per-axis power, while maintaining <1% non-linearity and a mechanical full-scale of >20 g, improving FoM by 15.6×.

  PublisherDOI

• The Effect of Corporate ESG Management Activities on Corporate Soft Power: Focusing on the Presentation of ESG Core Strategies and Priority of Importance

  Journal of Business Convergence · 2022-11-30 · 1 citations

  article

  본 연구는 이해관계자자본주의 사회에서 기업의 소프트파워를 강화시키고, 기업가치를 높이기 위한 전략적 대안으로 ESG 경영전략의 효과를 제시하고자 하였다. 기업의 환경(E) 활동을 5가지 전략으로 구분한 후(요인분석 후 3가지 전략으로 축소), 이들 전략이 기업 소프트파워에 미치는 효과를 살펴보았다. 그 결과, 경영자의 환경경영 실천의지 및 전략수립은 기업이미지, 기업평가, 그리고 기업평판에 긍정적인 영향을 미치는 것으로 나타났다. 환경위험관리 및 보고는 기업이미지와 기업평판에 긍정적인 영향을 미치는 것으로 나타났다. 사회(S)를 5가지 전략으로 구분하여 기업 소프트파워에 미치는 효과를 분석한 결과, 고용평등 및 확대전략은 기업이미지에 긍정적인 영향을 미쳤고, 근로환경 및 역량개발 전략은 기업이미지와 기업평판에 긍정적인 영향을 미치는 것으로 나타났으며, 소비자권리보호는 기업평가와 기업평판에 긍정적인 영향을 미치는 것으로 나타났다. 그리고 지역사회와 관련된 책임활동은 기업이미지 및 기업평가에 긍정적인 영향을 미치는 것으로 나타났으며, 이해관계자와의 상생협력은 기업평가에 긍정적인 영향을 미치는 것으로 나타났다. 지배구조(G)를 5가지 전략으로 구분하여 기업 소프트파워에 미치는 효과를 분석한 결과, 기업 건전성과 기업 공정성은 기업이미지 및 기업평판에 모두 유의한 정(+)의 영향을 미치는 것으로 나타났다. 기업공정성의 경우에는 기업평가에도 긍정적인 영향을 미쳤다. ESG 경영전략에 대한 핵심요소별 중요도 요인을 분석한 결과, 환경(E)과 관련해서는 실천 의지와 전략 수립이 중요한 요소로 인식되었고, 사회(S)는 소비자 권리 보호와 근로환경 개선, 고용 평등 순으로 중요도를 인식하였다. 지배구조(G)는 기업 건전성과 기업 공정성이 중요한 요인으로 인식되었다.

  PublisherDOI

• A 286nW, 103V High Voltage Generator and Multiplexer for Electrostatic Actuation in Programmable Matter

  2022 IEEE Symposium on VLSI Technology and Circuits (VLSI Technology and Circuits) · 2022-06-12 · 3 citations

  article

  We present a high-voltage-generation-and-multiplexing (HVGM) chip, specifically designed for electrostatic actuation of micro-robots. It can individually control 12 pairs of +/- electrodes using a positive and negative charge pump and mux-structure, consumes 286nW in steady state and 533nW when transitioning a 10pF electrode at 155V/s, and produces a differential voltage of 103V (29× voltage gain from 3.6V) in measurement. We also show a complete microsystem of stacked die, measuring 3×1.4×1.1mm, including HVGM, processor, radio, and harvester for energy autonomous operation.

  PublisherDOI

• A $\boldsymbol{210}\times \boldsymbol{340}\times \boldsymbol{50}\boldsymbol{\mu}\mathbf{m}$ Integrated CMOS System f0 $\mathbf{r}$ Micro-Robots with Energy Harvesting, Sensing, Processing, Communication and Actuation

  2022 IEEE International Solid- State Circuits Conference (ISSCC) · 2022-02-20 · 11 citations

  article

  Built upon significant research into ultra-low power CMOS designs, complete sub-mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> -wireless sensor systems have been introduced [1]–[7] that include energy harvesting, sensing, processing, and communication. However, a key missing component in such systems is actuation, which could enable a host of new applications. Recently, a new class of electrochemical actuators that operate at low voltage and low power were developed [8]. The lithographic fabrication of these actuators is CMOS compatible, offering an unprecedented opportunity to create micron-scale, monolithic micro-robots. From a circuit point of view, such micro-robots face three design challenges: 1) energy harvesting and voltage generation in ultra-small form factor; 2) a customized processor for compute efficiency with stringent area budget; 3) an energy and area-efficient communication link.

  PublisherDOI

Frequent coauthors

• David Blaauw

  University of Michigan–Ann Arbor

  70 shared

• Dennis Sylvester

  University of Michigan–Ann Arbor

  64 shared

• Inhee Lee

  Sogang University

  32 shared

• Gyouho Kim

  University of Michigan–Ann Arbor

  26 shared

• Seokhyeon Jeong

  22 shared

• Yoonmyung Lee

  Sungkyunkwan University

  21 shared

• Suyoung Bang

  Intel (United States)

  14 shared

• Zhiyoong Foo

  University of Michigan–Ann Arbor

  12 shared

Education

• Ph. D. in Electrical Engineering, Electrical Engineering and Computer Science

  University of Michigan

  2014

Awards & honors

• Sorantin International Competition
• Dichler-Sato International Competition
• Viva Hall Competition
• Korea Philharmonic Orchestra Competition