Younghyun Lim
Assistant professor, College of Electronics & Information
@Kyung Hee University, Seoul, South Korea, 2023.09 - Present
Contact Info.
Email : younghyun@khu.ac.kr, dudgus0262@gmail.com
Education
2011.03 - 2015.02
B.S. in Electrical and Computer Engineering
Ulsan National Institute of Science and Technology.
2015.03 - 2021.02
Combined M.S. & Ph.D. in Electrical and Computer Engineering
Ulsan National Institute of Science and Technology.
Research Interest
1. Power management IC (PMIC)
- Low-dropout (LDO) regulators
- Voltage and current references
2. Frequency synthesizer
- Sub-sampling phase-locked loop (SSPLL)
Experience
2019.09 - 2020.03
Internship at Qualcomm, San Diego, CA, USA.
2021.03 - 2023.09
Senior Engineer at Qualcomm, San Diego, CA, USA.
Publications
First Author
J. Kim, Y. Jo, T. Seong, H. Park, Y. Lim*, J. Choi*, "A 12.8–15.0-GHz Low-Jitter Fractional-N Subsampling PLL Using a Voltage-Domain Quantization-Error Cancellation," IEEE J. Solid-State Circuits (JSSC), Early Access.
Y. Lim, J. Kim, Y. Jo, J. Bang, and J. Choi, "A Wide-Lock-In-Range and Low-Jitter 12–14.5 GHz SSPLL Using a Low-Power Frequency-Disturbance-Detecting and Correcting Loop," IEEE Journal of Solid-State Circuits, Oct. 2021.
Y. Lim=, J. Kim=, Y. Jo, J. Bang, S. Yoo, H. Park, H. Yoon and J. Choi*, "A 170MHz-Lock-In-Range and -253dB-FOMJIT, 12-14.5GHz Subsampling PLL with ...," IEEE International Solid-State Circuits Conference (ISSCC), accepted for presentation, Feb. 2020. (= Equally-Credited Authors)
J. Kim=, H. Yoon=, Y. Lim=, Y. Lee, Y. Cho, T. Seong, and J. Choi, "A 76fsRMS-Jitter and −40dBc-Integrated-Phase-Noise 28−31GHz Frequency Synthesizer Based on Digital Sub-Sampling PLL," IEEE International Solid-State Circuits Conference (ISSCC), Feb. 2019. (= Equally-Credited Authors)
Y. Lim, J. Lee, S. Park, Y. Jo, and J. Choi, "An External Capacitorless Low-Dropout Regulator with High PSR at All Frequencies from 10 kHz to 1 GHz Using an Adaptive Supply-Ripple Cancellation Technique," IEEE Journal of Solid-State Circuits (JSSC), Sep. 2018.
Y. Lim, J. Lee, Y. Lee, S. Yoo, and J. Choi, "A 320uV-Output Ripple and 90ns-Settling Time at 0.5V Supply Digital-Analog-Hybrid LDO Using Multi-Level Gate-Voltage Generator and Fast-Decision PD Detector," IEEE European Solid-State Circuits Conference (ESSCIRC), Sep. 2018.
Y. Lim, J. Lee, Y. Lee, S. Song, H. Kim, and J. Choi, "An External Capacitor-Less Ultra-Low Dropout Regulator Using a Loop-Gain Stabilizing Technique for High Power Supply Rejection over a Wide Range of Load Current," IEEE Transactions on Very Large Scale Integration (VLSI) Systems, Nov. 2017.
Y. Lim, J. Lee, S. Park, and J. Choi, "An External-Capacitor-less Low-Dropout Regulator with Less than –36dB PSRR at All Frequencies from 10kHz to 1GHz Using an Adaptive Supply-Ripple Cancellation Technique to the Body-Gate," IEEE Custom Integrated Circuits Conference (CICC), May. 2017.
Y. Lim, J. Lee, S. Park, and J. Choi, "An External-Capacitor-Less High-PSR Low-Dropout Regulator Using an Adaptive Supply-Ripple Cancellation Technique to the Body-Gate," 2018 23rd Asia and South Pacific Design Automation Conference (ASP-DAC), 2018
Co-Author
J. Kim, Y. Lim, H. Yoon, Y. Lee, H. Park, Y. Cho, T. Seong, and J. Choi*, "An Ultra-Low-Jitter, mmW-Band Frequency Synthesizer Based on Digital Subsampling PLL Using Optimally-Spaced Voltage Comparators," IEEE Journal of Solid-State Circuits, accepted for publication.
J. Lee, J. Bang, Y. Lim, S. Yoo, Y. Lee, T. Seong, and J. Choi*, "A Fast-Transient and High-Accuracy, Adaptive-Sampling Digital LDO Uisng a Single VCO-Based Edge-Racing Time Quantizer," IEEE Solid-State Circuits Letters (SSC-L), accepted for publication, invited from IEEE 2019 Symp. VLSI Circuits.
J. Lee, J. Bang, Y. Lim, and J. Choi*, "A 0.5V-VIN, 0.29ps-Transient-FOM, and Sub-2mV-Accuracy Adaptive-Sampling Digital LDO Using Single-VCO-Based Edge-Racing Time Quantizer," IEEE Symp. VLSI Circuits Dig., Jun. 2019.
S. Choi, S. Yoo, Y. Lee, Y. Jo, J. Lee, Y. Lim, and J. Choi, "An Ultra-Low-Jitter 22.8-GHz Ring-LC-Hybrid Injection-Locked Clock Multiplier with a Multiplication Factor of 114," IEEE Journal of Solid-State Circuits (JSSC), Mar. 2019.
S. Yoo, S. Choi, Y. Lee, T. Seong, Y. Lim, and J. Choi, "A 140fsRMS-Jitter and −72dBc-Reference-Spur Ring-VCO-Based Injection-Locked Clock Multiplier," IEEE International Solid-State Circuits Conference (ISSCC), Feb. 2019.