Publications

INTERNATIONAL JOURNAL PAPERS

1. D. Choi and H.-K. Cha, "A low-power neural signal acquisition analog front-end IC for closed-loop neural interfaces", IEIE Journal of Semiconductor Technology and Science, vol.22, no.5, Oct. 2022

2. G. Paksi and H.-K. Cha, "A 15-V output highly-efficient charge pump IC for biomedical applications", IEIE Trans. on Smart Processing and Computing, vol. 11, no. 1, Feb. 2022

3. J.-Y. Son and H.-K. Cha, "An electrical stimulator IC with chopped pulse based active charge balancing for neural interface applications",  IEIE Journal of Semiconductor Technology and Science, vol.21, no.5, pp. 322-333, Oct. 2021

4. N. Nguyen and H.-K. Cha, "Design of a low-power 10-bit 250 kS/s SAR ADC for neural recording applications", IEIE Trans. on Smart Processing and Computing, vol. 10, no. 1, Feb. 2021

5. L. Tran and H.-K. Cha, "An ultra-low-power neural signal acquisition analog front-end IC", Elsevier Microelectronics Journal, vol.107, Jan. 2021

6. J.-Y. Son and H.-K. Cha, "An implantable neural stimulator IC with anodic current pulse modulation based active charge balancing", IEEE Access, vol.8, pp. 136449-136458, 2020

7. A. Abdi and H.-K. Cha, "A regulated multiple-output high-voltage charge pump IC for implantable neural stimulators", Elsevier Microelectronics Journal, vol.92, Oct. 2019

8. A. Abdi, H. S. Kim, H.-K. Cha, "A high-voltage generation charge-pump IC using input voltage modulated regulation for neural implant devices", IEEE Trans. on Circuits and Systems II, vol. 66, no. 3, pp. 342-346, Mar. 2019

9. L.-G. Tran, H.-K. Cha, W.-T. Park, "A compact wireless power transfer system at 915 MHz with supercapacitor for optogenetics applications ", Elsevier Sensors & Actuators: A. Physical,  vol.285, no.1, pp.386-394, Jan. 2019

10. H.-K. Cha, "A highly-integrated low-noise MICS band receiver RF front-end IC with AC-coupled current mirror amplifier", Journal of Circuits, Systems, and Computers, vol. 28, no. 1, Jan. 2019

11. H. S. Kim and H.-K. Cha, "An ultra low-power low-noise neural recording analog front-end IC for implantable devices",  IEIE Journal of Semiconductor Technology and Science, vol.18, no.4, pp.454-460, Aug. 2018

12. H. S. Kim and H.-K. Cha, "A low-noise biopotential CMOS amplifier IC using low-power two-stage OTA for neural recording applications", Journal of Circuits, Systems, and Computers, vol. 27, no. 5, May. 2018  

13. L.-G. Tran, H.-K. Cha, W.-T. Park, "RF energy harvesting: A review on designing methodologies and applications", Micro and Nano Systems Letters, Feb. 2017  

14. A. Abdi and H.-K. Cha, "A bidirectional neural interface CMOS analog front-end IC with embedded isolation switch for implantable devices", Elsevier Microelectronics Journal, vol. 58, pp. 70-75, Dec. 2016

15. H.-K. Cha, "A CMOS ultrasonic analogue front-end with a reconfigurable pulser/switch for medical imaging applications," IET Electronics Letters, vol.50, issue 20, pp. 1564-1566, Oct. 2015

16. A. Banuaji and H.-K. Cha, "A 15-V bidirectional ultrasound interface analog front-end IC for medical imaging using standard CMOS technology," IEEE Trans. on Circuits and Systems II,vol.61, no.8, Aug. 2014

17. H.-K. Cha and M. Je, "A single-input dual-output 13.56 MHz CMOS AC-DC converter with comparator-driven rectifiers for implantable devices,” Elsevier Microelectronics Journal, vol. 45, no. 3, pp. 277-281 Mar. 2014

18. H.-K. Cha, D. Zhao, J. H. Cheong, B. Guo, H. Yu, M. Je, "A CMOS high-voltage transmitter IC for ultrasound medical imaging applications," IEEE Trans. on Circuits and Systems II,vol.60, no.6, Jun. 2013

19. D. Zhao and H.-K. Cha, "A 30-V transmitter front-end IC for ultrasound medical imaging applications," Elsevier Microelectronics Journal, vol. 44, no.3, pp. 185-189, Mar. 2013

20. H.-K. Cha, D. L. Yan, M. K. Raja, M. Je, “A 1-V 1.2-mW CMOS MedRadio receiver for biomedical applications,”  Microwave and Optical Technology Letters, vol.54, no. 12, pp. 2821-2825, Dec. 2012

21. H.-K. Cha, W.-T. Park, M. Je, “A CMOS rectifier with cross-coupled latched comparator for wireless power transfer in biomedical applications,” IEEE Trans. on Circuits and Systems II, vol. 59, no. 7, pp. 409-413, Jul. 2012 (Ranked 3rd most cited paper in IEEE TCASII in the last 5 years , Dec. 2017)

22. H.-K. Cha, M. K. Raja, X. Yuan, M. Je, “A CMOS MedRadio receiver RF front-end with complementary current-reuse LNA,” IEEE Trans. on Microwave Theory and Techniques, vol.59, no.7, pp. 1846-1854, Jul. 2011

23. T. H. Teo, P. K. Gopalakrishnan, Y. S. Swan, X. Qian, K. Haridas, C. Y. Pang, H.-K. Cha, M. Je, “A 700-uW wireless sensor node SoC for continuous real-time health monitoring,” IEEE Journal of Solid-State Circuits, vol. 45, no.11, pp. 2292-2299, Nov. 2010

24. H.-K. Cha, “A CMOS RF programmable gain amplifier using current mirror method for digital TV tuner applications,” IEICE Trans. on Electronics, vol.E93-C, no.5, pp. 706-708, May. 2010

25. H.-K. Cha, “A CMOS sub-GHz wideband low-noise amplifier for digital TV tuner applications,” IEICE Trans. on Electronics, vol.E93-C, no.1,pp.142-144, Jan. 2010

26. H.-K. Cha, K. Kwon, J. Choi, H.-T. Kim, K. Lee, “A CMOS wideband RF front-end with mismatch calibrated harmonic rejection mixer for terrestrial digital TV tuner applications,” IEEE Trans. on Microwave Theory and Techniques, vol. 58, no.8, pp. 2143-2151, Aug. 2010

27. H.-K. Cha, S.-S. Song, H.-T. Kim, K. Lee, "A CMOS harmonic rejection mixer with mismatch calibration circuitry for digital TV tuner applications", IEEE Microwave and Wireless Components Letters, vol.18, no.9, pp. 617-619, Sept. 2008

28. I. Nam, K. Choi, J. Lee, H.-K. Cha, B. Seo, K. Kwon, K. Lee, "A 2.4 GHz low-power low-IF receiver and direct-conversion transmitter in 0.18μm CMOS for IEEE 802.15.4 WPAN applications", IEEE Trans. on Microwave Theory and Techniques, vol.55, no. 5, pp. 682-689, May 2007

29. H.-K. Cha, I. Yun, J. Kim, B.-C. So, K. Chun, I. Nam, K. Lee, "A 32-KB standard CMOS antifuse one-time programmable ROM embedded in a 16-b microcontroller", IEEE Journal of Solid-State Circuits, vol. 41, no.9, pp. 2115-2124, Sept. 2006

30. H.-K. Cha, J. Kim, K. Lee, "A high-density 64K-bit one time programmable ROM array with 3-transistor cell standard CMOS gate-oxide antifuse", IEIE Journal of Semiconductor Technology and Science, Vol 4, no. 2, pp.106-109, June 2004.

INTERNATIONAL CONFERENCE PAPERS

1. H. Yoo and H.-K. Cha, "A biopotential amplifier IC with active common-mode cancellation for closed-loop neural interfaces", in 19th International SoC Design Conference (ISOCC) 2022, Oct. 2022

2. S. Hong and H.-K. Cha, "A power-efficient low-noise neural recording amplifier IC with high tolerance to stimulation artifacts", in 19th International SoC Design Conference (ISOCC) 2022, Oct. 2022

3. D. Choi, S. Hong, H. Yoo, H.-K. Cha, "An ultra-low-power biopotential recording analog front-end IC for closed-loop neural interfaces", in 19th International SoC Design Conference (ISOCC) 2022 Chip Design Contest (CDC), Oct. 2022

4. D. Choi and H.-K. Cha, "A low-power low-noise neural signal acquisition amplifier with tolerance to large stimulation artifacts", in 18th International SoC Design Conference (ISOCC) 2021, Oct. 2021

5. G. Paksi and H.-K. Cha, "A 15-V output highly-efficient charge pump IC for biomedical applications", in 17th International SoC Design Conference (ISOCC) 2020 Chip Design Contest (CDC), Oct. 2020

6. L. Tran and H.-K. Cha, "A power-efficient low-noise neural recording analog front-end IC for implantable medical devices", in 34th International Technical Conference on Circuits/Systems, Computers, and Communications (ITC-CSCC) 2019, Jun. 2019

7. J.-Y. Son and H.-K. Cha, "An anodic current pulse modulation active charge balancer for implantable electrical stimulator", in 34th International Technical Conference on Circuits/Systems, Computers, and Communications (ITC-CSCC) 2019, Jun. 2019 

8. J.-Y. Son and H.-K. Cha, "A charge balanced neural stimulator using chopped anodic pulse control", in 34th International Technical Conference on Circuits/Systems, Computers, and Communications (ITC-CSCC) 2019, Jun. 2019 

9. H. S. Kim, M.-G. Song, H.-K. Cha, "A multi-channel low-noise CMOS analog front-end IC for neural recording SoCs", in 15th International SoC Design Conference (ISOCC) 2018 Chip Design Contest (CDC), Nov. 2018

10. M.-G. Song and H.-K. Cha, "A high PSRR capacitorless LDO regulator for implantable medical devices", in 33rd International Technical Conference on Circuits/Systems, Computers, and Communications (ITC-CSCC) 2018, Jul. 2018

11. H. S. Kim and H.-K. Cha, "A low-noise neural amplifier IC using two-stage OTA for biomedical applications", in 14th International SoC Design Conference (ISOCC) 2017 Chip Design Contest (CDC), Nov. 2017

12. T. N. Vo and H.-K. Cha, "A standard CMOS neural stimulator IC with high voltage compliant output current driver", in 14th International SoC Design Conference (ISOCC) 2017, Nov. 2017

13. F. Uftiani and H.-K. Cha, "A low-power low-noise ultrasonic receiver front-end IC for medical imaging systems", in 14th International SoC Design Conference (ISOCC) 2017, Nov. 2017

14. H. S. Kim and H.-K. Cha, "A micropower biopotential amplifier IC employing cascoded complementary input OTA for bidirectional neural system-on-chips", in 32nd International Technical Conference on Circuits/Systems, Computers, and Communications (ITC-CSCC) 2017, Jul. 2017

15. A. Banuaji and H.-K. Cha, "A highly-integrated low-voltage transimpedance preamplifier for medical ultrasound imaging systems", in 16th International Conference on Electronics, Information, and Communication (ICEIC) 2017, Jan. 2017

16. H. S. Kim and H.-K. Cha, "A low-power, low-noise neural recording amplifier for implantable biomedical devices", in 13th International SoC Design Conference (ISOCC) 2016, Oct. 2016

17. H. S. Kim and H.-K. Cha, "A low-power capacitive-feedback CMOS neural recording amplifier for biomedical applications", in 13th International SoC Design Conference (ISOCC) 2016, Oct. 2016

18. M. Je, J. H. Cheong, C. K. Ho, S. S. Y. Ng, R.-F. Xue, H.-K. Cha, X. Liu, W.-T. Park, L. S. Lim, C. He, K.-W. Cheng, X. Zou, Z. Chen, L. Yao, S.-J. Cheng, P. Li, L. Liu, M.-Y. Cheng, Z. Duan, R. Rajkumar, Y. Zheng, W. L. Goh, Y. Guo, G. Dawe, "Wireless sensor microsystems for emerging biomedical applications", Radio-Frequency Integration Technology (RFIT), 2015 IEEE International Symposium on, pp. 139-141, 2015 (invited)

19. X. Huang, J. H. Cheong, H.-K. Cha, H. Yu, M. Je, H. Yu, "A high-frequency transimpedance amplifier for CMOS integrated 2D CMUT array towards 3D ultrasound imaging," in International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC'13), Jul. 2013

20. K.-W. Cheng, X. Zou, Z. Chen, R.-F. Xue, J. H. Cheong, L. Yao, H.-K. Cha, S.-J. Cheng, P. Li, L. Liu, L. Andia, C. K. Ho, M.-Y. Cheng, Z. Duan, R. Rajkumar, Y. Zheng, W. L. Goh, Y. Guo, G. S. Dawe, W.-T. Park, M. Je, "100-channel wireless neural recording system with 54-Mb/S data link and 40%-efficiency power link,"  in IEEE Asian Solid-State Circuits Conference (ASSCC) 2012, Nov. 2012

21. J. H. Cheong, C. K. Ho, S. S. Y. Ng, R.-F. Xue, H.-K. Cha, P. B. Khannur, X. Liu, A. A. Lee, F. N. Endru, W.-T. Park,L. S. Lim, C. He, M. Je, "A wirelessly powered and interrogated blood flow monitoring microsystem fully integrated with a prosthetic vascular graft for early failure detection,"  in IEEE Asian Solid-State Circuits Conference (ASSCC) 2012, Nov. 2012

22. D. Zhao, M. T. Tan, H.-K. Cha, J. Qu, M. Yan, H. Yu, A. Basu, M. Je, “High-voltage pulser for ultrasound medical imaging applications”, in IEEE Int. Symp. Integrated Circuits (ISIC) 2011, Dec. 2011

23. R.-F. Xue, H.-K. Cha, J.H. Cheong, P. B. Khannur, M. Je, Y. Zheng, “Wireless powering and bidirectional telemetry front-end for implantable biomedical devices”, in IEEE Int. Symp. Integrated Circuits (ISIC) 2011, Dec. 2011  

24. R.-F. Xue, J. H. Cheong, H.-K. Cha, X. Liu, P. Li, H. J. Lim, L. S. Lim, M.-Y. Cheng, C. He, M. Hamidullah, W.-T. Park, M. Je, “Ultra-low-power wireless implantable blood flow sensing microsystem for vascular graft applications”, in IEEE Int. Symp. Integrated Circuits (ISIC) 2011, Dec. 2011 

25. R.-F. Xue, P. B. Khannur, H.-K. Cha, Y. Zheng, M. Je, “High-efficiency transcutaneous wireless energy transfer for biomedical applications”, in Defense Science Research Conf. and Expo (DSR) 2011, Aug. 2011 

26. H.-K. Cha, M. K. Raja, X. Yuan, M. Je, “A CMOS MedRadio receiver RF front-end with complementary current-reuse LNA for biomedical applications”, in IEEE Asian Solid-State Circuits Conference (ASSCC) 2010, Nov. 2010

27. R.-F. Xue, P. B. Khannur, K. Kang, H.-K. Cha, Y. Zheng, M. Je, “Efficient wireless powering link for biomedical implant application”, in Asia-Pacific Signal and Information Processing Association (APSIPA) Annual Summit and Conference 2010, Nov. 2010

DOMESTIC JOURNAL/CONFERENCE PAPERS

Journals

1. H. Yoo and H.-K. Cha, "A common mode artifact tolerant low-power low-noise neural recording chopper amplifier", 대한전자공학회 논문집 (J. of the IEIE) SD편 60권, 12호, 2023

2. J.-Y. Son and H.-K. Cha, "An ultra low-power low-noise neural signal acquisition amplifier for ECoG applications", IDEC Journal of Integrated Circuits and Systems (JICAS), vol.9, no.4, Oct. 2023 

3. S. Hong and H.-K. Cha, "A low-power reconfigurable neural interface analog front-end IC with common-mode artifact cancellation loop", 대한전자공학회 논문집 (J. of the IEIE) SD편 60권, 6호, 2023

4. J.-Y. Son and H.-K. Cha, "An ultra low-power ECoG signal recording analog front-end IC",  대한전자공학회 논문집 (J. of the IEIE) SD편 57권, 8호, 2020

5. M.-G. Song and H.-K. Cha, "A fully-integrated high-voltage generation IC for implantable medical devices", IDEC Journal of Integrated Circuits and Systems (JICAS) , vol.5, no.4, Oct. 2019 

6. J.-Y. Son and H.-K. Cha, "A charge balanced neural stimulation integrated circuit with chopped anodic pulse control", 대한전자공학회 논문집 (J. of the IEIE) SD편 56권, 9호, 2019

7. F. Uftiani and H.-K Cha, "A reconfigurable ultrasonic analog front-end IC for medical imaging applications", IDEC Journal of Integrated Circuits and Systems (JICAS) , vol.4, no.2, Apr. 2018 

8. H. S. Kim and H.-K. Cha, "An ultra low-power low-noise dual-channel CMOS neural recording analog IC", 대한전자공학회 논문집 (J. of the IEIE) SD편 55권, 3호, 2018 

9. H.-K. Cha, "A low-voltage low-power analog front-end IC for neural recording implant devices", 대한전자공학회 논문집 (J. of the IEIE) SD편 53권, 10호, 2016 

10.  A. Abdi and H.-K. Cha, "A high-voltage compliant neural stimulation IC for implant devices using standard CMOS process", 대한전자공학회 논문집 (J. of the IEIE) SD편, 52권, 5호, 2015 

11. H.-K. Cha, "A reconfigurable analog front-end integrated circuit for medical ultrasound imaging systems", 대한전자공학회 논문집 (J. of the IEIE) SD편, 51권, 12호, 2014 

12. A. Banuaji and H.-K. Cha, "A highly-integrated analog front-end IC for medical ultrasound imaging systems", 대한전자공학회 논문집 (J. of the IEIE) SD편, 50권, 12호, 2013

13. H.-K. Cha, "A 13.56 MHz CMOS multi-stage rectifier for wireless power transfer in biomedical applications", 대한전자공학회 논문집 (Journal of the IEIE) SD편, 50권, 3호, 2013

14. H.-K. Cha, "초음파 의료 영상 응용 분야를 위한 CMOS 집적회로 연구 개발", 대한전자공학회 전자공학회지 (Magazine of the IEIE), 40권, 6호, 2013 (invited)   

Conferences

1. H. Yoo and H.-K. Cha, "전류 미러 OTA 기반 PGA와 협대역 버퍼 대역폭 제어를 사용한 저전력 뉴럴 인터페이스 아날로그 프론트엔드", 대한전자공학회 추계학술대회 (Autumn Annual Conf. of IEIE) , Nov. 2022

2. S. Hong and H.-K. Cha, "큰 입력 임피던스를 가지며 최대 1Vpp 공통모드 간섭에 내성이 있는 LFP대역 초저전력, 저잡음 초퍼 증폭기", 대한전자공학회 추계학술대회 (Autumn Annual Conf. of IEIE) , Nov. 2022

3. J.-Y. Son, D. Choi, H.-K. Cha, "A low-power low-noise neural recording amplifier for ECoG applications", 제 29회 한국반도체학술대회 (29th Korean Conference on Semiconductors) Chip Design Contest, Jan. 2022

4. D. Choi and H.-K. Cha, "자극 아티팩트에 내성이 있는 신경 신호 기록을 위한 저전력, 저잡음 초퍼 증폭기", 대한전자공학회 추계학술대회 (Autumn Annual Conf. of IEIE) , Nov. 2021

5. Y. J. Lee, D. Choi, H.-K. Cha, "Floating-body가 적용된 저잡음 뇌신경 신호 처리 증폭기 집적회로", 대한전자공학회 추계학술대회 (Autumn Annual Conf. of IEIE) , Nov. 2021 

6. L. Tran and H.-K. Cha, "A low-noise neural recording analog front-end IC for implantable devices", 제 28회 한국반도체학술대회 (28th Korean Conference on Semiconductors) Chip Design Contest, Jan. 2021

7. J.-Y. Son and H.-K. Cha, "A 340nW 11-bit 100-kS/s SAR ADC with even/odd comparator for biomedical implant devices",  제 27회 한국반도체학술대회 (27th Korean Conference on Semiconductors), Feb. 2020 

8. M.-G. Song, G. Paksi, H.-K. Cha, "A 12.8-V output fully-integrated high-voltage charge pump IC for implantable devices", 제 27회 한국반도체학술대회 (27th Korean Conference on Semiconductors) Chip Design Contest, Feb. 2020 (현장우수포스터상 수상, Best Poster Award)

9. J.-Y. Son and H.-K. Cha, "An implantable electrical stimulator using anodic current modulation active charge balancer", 2019 SoC Conference, May. 2019

10. H. S. Kim, M.-G. Song, H.-K. Cha, "A low-power low-noise CMOS analog front-end IC for neural recording systems", 제 25회 한국반도체학술대회 (25th Korean Conference on Semiconductors) Chip Design Contest, Feb. 2018 

11. H. Kim , H. Park, H. S. Kim, H.-K. Cha, " An ultra low-power highly-integrated analog front-end IC for ECoG recording", 대한전자공학회 추계학술대회 (Autumn Annual Conf. of IEIE), Nov. 2017 

12.  L.-G. Tran, H.-K. Cha, W.-T. Park, " RF power harvesting and storage system with supercapacitor for biomedical applications ", 제19회 Korean MEMS 학술대회 , Mar. 2017 

13. S. Oh, S. Park, M. Jee, N. Kim, H.-K. Cha, "A bidirectional analog signal processing IC for medical ultrasound imaging systems", 대한전자공학회 추계학술대회 (Autumn Annual Conf. of IEIE) , Nov. 2016 

14. L.-G. Tran, H.-K. Cha, W.-T. Park, " Radio frequency energy harvesting with various stages of voltage multiplier ", 제18회 Korean MEMS 학술대회 (Korean MEMS Conf.), Apr. 2016 

15. A. Abdi, H. S. Kim, H.-K. Cha, " A low-power CMOS neural amplifier IC for implantable medical devices", 제 23회 한국반도체학술대회 (23rd Korean Conference on Semiconductors) Chip Design Contest, Feb. 2016 

16. L.-G. Tran, H.-K. Cha, W.-T. Park, "Radio frequency energy harvesting for biomedical application", 대한기계학회 추계학술대회 (Summer Annual Conf. of KSME), vol. 15, Nov. 2015  

PATENTS GRANTED/PENDING

1. H. S. Kim and H.-K. Cha, "뇌신경 기록용 아날로그 프론트엔드 집적회로", Korea patent number 10-2076627, Feb. 2020

2. H.-K. Cha, "Reconfigurable analog front-end IC and ultrasound image system using such IC", Korea patent number 10-1592521, Feb. 2016 

3. H.-K. Cha and A. Banuaji, "High-voltage highly-integrated analog front-end IC and ultrasound image system using such IC", Korea patent number 10-1626507, June. 2016 

4. R.-F. Xue, J. H. Cheong, H.-K. Cha , M. Je , “Power transfer device ”, US Patent 9,240,690 , Jan.16. 2016 

5.  H.-K. Cha , Y. Gao, X. Yuan, "Amplifier and transceiver including the amplifier”, Singapore patent filed WO/2011/149426 , May 25. 2011 

6. I. Nam, H.-K. Cha , B. Seo, J. Kim, K. Lee, “Circuits using CMOS ROM”, Korea patent granted 10-0831750-0000, May. 2008 

7. H.-K. Cha , S.-H. Chu, K. Lee, H.-T. Kim, “ Harmonic rejection polyphase mixer using capacitance scaling”, Korea patent filed 10-2007-0055167, Jun. 5, 2007 

8. S.-H. Chu, H.-K. Cha , K. Lee, H.-T. Kim, “Harmonic rejection mixer using FIR filtering”, Korea Patent Pending 10-2007-0055166, Jun. 5, 2007 

9. K. Lee, H.-K. Cha , H.-T. Kim, “ Wideband receiver”, Korea patent filed , 10-2007-0004396, Jan. 15, 2007 

10. H.-K. Cha , K. Lee, H.-T. Kim, “ RF programmable gain amplifier using current amplification”, Korea patent filed 10-2006-0118745 , Nov. 29, 2006 

11. K. Lee, J. Kim, H.-K. Cha , "3-transistor OTP ROM using CMOS gate oxide antifuse", US patent granted, US 6927997, Aug. 2005