{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,14]],"date-time":"2025-10-14T00:36:11Z","timestamp":1760402171874,"version":"build-2065373602"},"reference-count":24,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2022,1,11]],"date-time":"2022-01-11T00:00:00Z","timestamp":1641859200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["2020R1A2C1008879"],"award-info":[{"award-number":["2020R1A2C1008879"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper presents a nine-bit integrator-based time-to-digital converter (I-TDC) realized in a 180 nm CMOS technology for the applications of indoor home-monitoring light detection and ranging (LiDAR) sensors. The proposed I-TDC exploits a clock-free configuration so as to discard clock-related dynamic power consumption and some notorious issues such as skew, glitch, and synchronization. It consists of a one-dimensional (1D) flash TDC to generate coarse-control codes and an integrator with a peak detection and hold (PDH) circuit to produce fine-control codes. A thermometer-to-binary converter is added to the 1D flash TDC, yielding four-bit coarse codes so that the measured detection range can be represented by nine-bit digital codes in total. Test chips of the proposed I-TDC demonstrate the measured results of the 53 dB dynamic range, i.e., the maximum detection range of 33.6 m and the minimum range of 7.5 cm. The chip core occupies the area of 0.14 \u00d7 1.4 mm2, with the power dissipation of 1.6 mW from a single 1.2-V supply.<\/jats:p>","DOI":"10.3390\/s22020554","type":"journal-article","created":{"date-parts":[[2022,1,11]],"date-time":"2022-01-11T20:33:04Z","timestamp":1641933184000},"page":"554","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["A CMOS Integrator-Based Clock-Free Time-to-Digital Converter for Home-Monitoring LiDAR Sensors"],"prefix":"10.3390","volume":"22","author":[{"given":"Ying","family":"He","sequence":"first","affiliation":[{"name":"Department of Electronic and Electrical Engineering, Ewha Womans University, Seoul 03760, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sung Min","family":"Park","sequence":"additional","affiliation":[{"name":"Department of Electronic and Electrical Engineering, Ewha Womans University, Seoul 03760, Korea"},{"name":"Graduate Program in Smart Factory, Ewha Womans University, Seoul 03760, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,1,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"550","DOI":"10.1109\/TCSI.2016.2619762","article-title":"A Wide Dynamic Range CMOS Laser Radar receiver with a Time-Domain Walk Error Compensation Scheme","volume":"64","author":"Kurtti","year":"2017","journal-title":"IEEE Trans. Circuits Syst. Regul. I"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"5589","DOI":"10.1109\/JSEN.2020.3043797","article-title":"Mirrored Current-Conveyor Transimpedance Amplifier for Home Monitoring LiDAR Sensors","volume":"21","author":"Yoon","year":"2021","journal-title":"IEEE Sens. J."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"4098237","DOI":"10.1155\/2018\/4098237","article-title":"An Elderly Care System Based on Multiple Information Fusion","volume":"2018","author":"He","year":"2018","journal-title":"J. Healthc. Eng."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"2684","DOI":"10.1109\/TIM.2018.2826860","article-title":"A Linear Dynamic Range Receiver with Timing Discrimination for Pulsed TOF Imaging LADAR Application","volume":"67","author":"Zheng","year":"2018","journal-title":"IEEE Trans. Instrum. Meas."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"146","DOI":"10.1109\/TIM.2010.2047663","article-title":"An Integrated Laser Radar Receiver Channel Utilizing a Time-Domain Walk Error Compensation Scheme","volume":"60","author":"Kurtti","year":"2011","journal-title":"IEEE Trans. Instrum. Meas."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"2208","DOI":"10.1109\/TIM.2019.2918372","article-title":"A CMOS Receiver-TDC Chip Set for Accurate Pulsed TOF Laser Ranging","volume":"69","author":"Kurtti","year":"2020","journal-title":"IEEE Trans. Instrum. Meas."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"5053","DOI":"10.1109\/JSEN.2019.2905267","article-title":"A Linear-Array Receiver Analog Front-End Circuit for Rotating Scanner LiDAR Application","volume":"19","author":"Zheng","year":"2019","journal-title":"IEEE Sens. J."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1486","DOI":"10.1109\/JSSC.2009.2017006","article-title":"Integrated Receiver Including Both Receiver Channel and TDC for a Pulsed Time-of-Flight Laser Rangefinder With cm-Level Accuracy","volume":"44","author":"Nissinen","year":"2009","journal-title":"IEEE J. Solid State Circuits"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"3007","DOI":"10.1109\/TCSI.2014.2327282","article-title":"A High-Sensitivity and Low-Walk Error LADAR Receiver for Military Application","volume":"61","author":"Cho","year":"2014","journal-title":"IEEE Trans. Circuits Syst. Regul. I"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"1286","DOI":"10.1109\/JSSC.2006.874281","article-title":"A CMOS Time-to-Digital Converter with Better Than 10ps Single-Shop Precision","volume":"41","author":"Jansson","year":"2006","journal-title":"IEEE J. Solid State Circuits"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"2513","DOI":"10.1109\/JSSC.2019.2927871","article-title":"Analysis and Correction of Noise Injection Due to Parallel-Output-Misalignment(POM) Effects in Ring-Type Time-to-Digital Converters(TDCs)","volume":"54","author":"Wang","year":"2019","journal-title":"IEEE J. Solid State Circuits"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1626","DOI":"10.1109\/4.823449","article-title":"A High-Resolution CMOS Time-to-Digital Converter Utilizing a Vernier Delay Line","volume":"35","author":"Dudek","year":"2000","journal-title":"IEEE J. Solid State Circuits"},{"key":"ref_13","first-page":"1169","article-title":"Comparative Study of Delay Line Based Time to Digital Converter Using FPGA","volume":"04","author":"Soni","year":"2017","journal-title":"Int. Res. J. Eng. Technol."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1511","DOI":"10.1109\/TCSI.2011.2158490","article-title":"A Cyclic Vernier TDC for ADPLLs Synthesized from a Standard Cell Library","volume":"58","author":"Park","year":"2011","journal-title":"IEEE Trans. Circuits Syst. I Reg. Pap."},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Straayer, M.Z., and Perrott, M.H. (2008, January 18\u201320). An efficient high-resolution 11-bit noise-shaping multipath gated ring oscillator TDC. Proceedings of the IEEE Symposium on VLSI Circuits, Honolulu, HI, USA.","DOI":"10.1109\/VLSIC.2008.4585960"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"1009","DOI":"10.1109\/JSSC.2013.2237996","article-title":"A 7 bit, 3.75 ps Resolution Two-Step Time-to-Digital Converter in 65 nm CMOS Using Pulse-Train Time Amplifier","volume":"48","author":"Kim","year":"2013","journal-title":"IEEE J. Solid State Circuits"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"839","DOI":"10.1109\/JSSC.2017.2782766","article-title":"A 9-bit 215 MS\/s Folding-Flash Time-to-Digital Converter Based on Redundant Remainder Number System in 45-nm CMOS","volume":"53","author":"Wu","year":"2018","journal-title":"IEEE J. Solid State Circuits"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"533","DOI":"10.1016\/S0168-9002(01)02059-9","article-title":"Analog CMOS peak detect and hold circuits. Part 1. Analysis of the classical configuration","volume":"484","author":"Geronimo","year":"2002","journal-title":"Nuclear Instrum. Methods Phys. Res. Sect. A Accel. Spectrometers Detect. Assoc. Equip."},{"key":"ref_19","first-page":"124","article-title":"A 5-bit time to digital converter using time to voltage conversion and integrating techniques for agricultural products analysis by Raman Spectroscopy","volume":"1","author":"Rezvanyvardom","year":"2014","journal-title":"Inform. Proc. Agric."},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Nguyen, V.N., Duong, D.N., Chuang, Y., and Lee, J.-W. (2018). A Cyclic Vernier Two-Step TDC for High Input Range Time-of-Flight Sensor Using Startup Time Correction Technique. Sensors, 18.","DOI":"10.3390\/s18113948"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"543","DOI":"10.5573\/JSTS.2020.20.6.543","article-title":"A 3-dimensional Modified Vernier Time-to-digital Converter for LiDAR Sensors","volume":"20","author":"He","year":"2020","journal-title":"J. Semicond. Tech. Sci."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"2326","DOI":"10.1109\/TCSI.2014.2304656","article-title":"An 11b 7ps Resolution Two-Step Time-to-Digital Converter with 3-D Vernier Space","volume":"61","author":"Kim","year":"2014","journal-title":"IEEE Trans. Circuits Syst. I Reg. Pap."},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Seo, H., Yoon, H., Kim, D., Kim, J., Kim, S.-J., Chun, J.-H., and Choi, J. (2020, January 16\u201319). AA 36-channel SPAD-integrated scanning LiDAR sensor with multi-event histogramming TDC and embedded interference filter. Proceedings of the Symposium on VLSI Circuits, Honolulu, HI, USA.","DOI":"10.1109\/VLSICircuits18222.2020.9162807"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"753","DOI":"10.1109\/TCSI.2019.2955671","article-title":"A 60-m Range 6.16-mW Laser Power Linear-Mode LiDAR System with Multiplex ADC\/TDC in 65-nm CMOS","volume":"67","author":"Liu","year":"2020","journal-title":"IEEE Trans. Circuits Syst. I Reg. Pap."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/22\/2\/554\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,13]],"date-time":"2025-10-13T13:27:16Z","timestamp":1760362036000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/22\/2\/554"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,1,11]]},"references-count":24,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2022,1]]}},"alternative-id":["s22020554"],"URL":"https:\/\/doi.org\/10.3390\/s22020554","relation":{},"ISSN":["1424-8220"],"issn-type":[{"type":"electronic","value":"1424-8220"}],"subject":[],"published":{"date-parts":[[2022,1,11]]}}}