{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T01:37:42Z","timestamp":1760233062670,"version":"build-2065373602"},"reference-count":30,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2022,12,10]],"date-time":"2022-12-10T00:00:00Z","timestamp":1670630400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"a grant-in-aid of KRIT and HANWHA SYSTEMS through the Weapon Systems Parts Localization R&amp;D program","award":["C210042"],"award-info":[{"award-number":["C210042"]}]},{"name":"grant-in-aid of HANWHA SYSTEMS","award":["C210042"],"award-info":[{"award-number":["C210042"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A direct feedback flipped voltage follower (FVF) LDO for a high-precision frequency-modulated continuous-wave (FMCW) radar is presented. To minimize the effect of the power supply ripple on the FMCW radar sensor\u2019s resolution, a folded cascode error amplifier (EA) was connected to the outer loop of the FVF to increase the open-loop gain. The direct feedback structure enhances the PSRR while minimizing the power supply ripple path and not compromising a transient response. The flipped voltage follower with a super source follower forms a fast feedback loop. The stability and parameter variation sensitivity of the multi-loop FVF LDO were analyzed through the state matrix decomposition. We implemented the FVF LDO in TSMC 65 nm CMOS technology. The fabricated FVF LDO supplied a maximum load current of 20 mA with a 1.2 V power supply. The proposed FVF LDO achieved a full-spectrum PSR with a low-frequency PSRR of 66 dB, unity-gain bandwidth of 469 MHz, and 20 ns transient settling time with a load current step from 1 mA to 20 mA.<\/jats:p>","DOI":"10.3390\/s22249672","type":"journal-article","created":{"date-parts":[[2022,12,12]],"date-time":"2022-12-12T05:10:19Z","timestamp":1670821819000},"page":"9672","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["A Direct Feedback FVF LDO for High Precision FMCW Radar Sensors in 65-nm CMOS Technology"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8476-5542","authenticated-orcid":false,"given":"Jun-Hee","family":"Lee","sequence":"first","affiliation":[{"name":"Division of Electronics and Electrical Engineering, Dongguk University, Seoul 04620, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mun-Kyo","family":"Lee","sequence":"additional","affiliation":[{"name":"Yongin Research Institute, Hanwha Systems, Yongin-si 17121, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4733-2160","authenticated-orcid":false,"given":"Jung-Dong","family":"Park","sequence":"additional","affiliation":[{"name":"Division of Electronics and Electrical Engineering, Dongguk University, Seoul 04620, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,12,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"151403","DOI":"10.1109\/ACCESS.2020.3016689","article-title":"Fully Integrated Dual-Mode X-Band Radar Transceiver Using Configurable Receiver and Local Oscillator","volume":"8","author":"Ha","year":"2020","journal-title":"IEEE Access"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"233","DOI":"10.1109\/JSSC.2019.2950184","article-title":"A CMOS 76\u201381-GHz 2-TX 3-RX FMCW Radar Transceiver Based on Mixed-Mode PLL Chirp Generator","volume":"55","author":"Ma","year":"2020","journal-title":"IEEE J. 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