Sinem ÖLMEZUğur ÇAMÇam, UğurÖlmez, Sinem2025-10-222010[1] Y. P. Tsividis V. Gopinathan L. T´oth “Companding in signal processing” Electronics Letters Vol. 26 pp. 1331– 1332 1990.[2] R. W. Adams “Filtering in the log-domain” Presented at 63rd AES Conference May 1979.[3] E. Seevinck “Companding current-mode integrator: A new circuit principle for continuous-time monolithic filters” Electronics Letters Vol. 26 No. 24 pp. 2046–2047 1990.[4] D. R. Frey “State space synthesis of log domain filters” IEEE International Symposium on Circuits and Systems 1 pp. 481–484 1997.[5] D. R. Frey “Log-domain filtering: an approach to current mode filtering” IEE Proc.-G Circuits Devices and Systems Vol. 140 No. 6 pp. 406–416 1993.[6] D. R. Frey “Exponential state-space filters: A generic current-mode design strategy” IEEE Trans. on Circuits and Systems-I: Fundamental Theory and Application Vol. 43 pp. 34–42 1996.[7] C. Toumazou J. Ngarmnil T.S Lande “Micropower log-domain filter for electronic cochlea” Electronics Letters Vol. 30 No. 22 pp. 1839–1841 1994.[8] M. H. Eskiyerli A. J. Payne C. Toumazou “State space synthesis of integrators based on the MOSFET square law” Electronics Letters Vol. 32 No. 6 pp. 505–506. 1996.[9] R. Schaumann M. E. V Valkenburg. Design of analog filters.Oxford: Oxford University Press, 2001.[10] S. Ozoguz T. M. Abdelrahman A. S. Elwakil “Novel Approximate Square-Root Domain All-pass Filter with Application to Multiphase Oscillators” Analog Integrated Circuits and Signal Processing Vol. 46 No. 3 pp. 297– 301 2006[11] A. Kırcay & U. Cam A novel first-order log-domain all-pass filter Int. Journal of Electronics and Communications (AEUE) Vol. 60 No. 6 pp. 471–474 2006.[12] K. Bult A. Wallinga “A class of analog CMOS circuits based on the square-law characteristic of an MOS transistor in saturation” IEEE Journal of solid-state circuits Vol. 22 No. 3 pp. 357–365 1987.[13] G. Yu C. Huang B. Liu J. Chen “Design of Square-Root Domain Filters” Analog Integrated Circuits and Signal Processing Vol. 43 pp. 49–59 2005.1300-06321303-620310.3906/elk-0904-112-s2.0-76749121471https://gcris.yasar.edu.tr/handle/123456789/11256https://search.trdizin.gov.tr/en/yayin/detay/96310https://doi.org/10.3906/elk-0904-11In this paper a new square-root domain first order all-pass filter based on the MOSFET square law is presented. The proposed filter is designed by using nonlinear mapping on the state variables of a state space description of the transfer function. To the best knowledge of the authors the filter is the first square-root domain first order all-pass structure designed by using state space synthesis method in the literature. The center frequency of the all-pass filter is not only attainable at megahertz frequencies but also tunable by an external bias current. The proposed filter operated 2.5 V supply voltage is constructed by current mirrors geometric mean circuits a linear transconductor circuit and a capacitor. SPICE simulations are given to approve the theoretical analysis.İngilizceinfo:eu-repo/semantics/openAccessMühendislik- Elektrik ve ElektronikState-Space SynthesisSlate-Space SynthesisMühendislik, Elektrik Ve ElektronikSquare-Root Domain CircuitsAll-Pass FilterArticle