CMOS programmable gain circuits: amplifiers and current conveyors

Date
2005
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Abstract
CJ\IOS programmable gain stages form essential building blocks i11 today's Lclccom­m1wicat.iou sys Le ms. For each specific application, there may lie a myriad of poLcnt.ial solnt.ious: however, not all soluLiom; are equally suited Lo solving all problems. Sornc problems may be directly treated with traditional voltage-mode approaches while ot.lier problems may lie more efficiently tackled via less convcnLiomt! currcut-modc methods. In view of such an expansive landscape, the present. work seeks Lo investi­gate t.wo telecommunication applications and Lhe specific solnt.iuu for each. FirsLly, a LradiLional Programmable Gain Amplifier (PGA) is clcsig11ccl for 11:-:c ui Very J-1.igh-Spccd Digit.al Suli:-:cribcr Loops (VDSL). Wide lm,ndwidLh, low noi:-:c, aml high Ii neariLy arc achicve<l using a fully cliffcrcnt.ial, multi-stage, vo!Lagc-modc amplifier with switched resistive feedback Lo set the gain. The pscuclo-consLaul. signal liaudwidt.h is accomplii-;l1ed using switched nested Miller co111pensat.ion for each gain :-:ctt.ing t.o keep Lhe dosed-loop lianclwidLh relatively constant.. Secondly, a novel Programmable Gain Current Conveyor (CCII) is dcsigucd !or use in a T 1 /El Equa.li:t,er Line Int.er face U 11iL (LIU). Being digitally t.nrn,1.blc, t.bc upcu­loop CCII has high input impedance, low output impedance and consLa.nL handwidt.h 1-H:ross all gain set.Lings. l3ot.h programmable gain sLages have been designed am! fabrica.Lcd in Lhc TSMC CMOS 0.35 ??l'm process. Del.ailed analysis, simulation and rucasurcmeuLs a.re shown wit.hiu Lhis thesis.
Description
Bibliography: p. 117-123
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Citation
Quan, J. (2005). CMOS programmable gain circuits: amplifiers and current conveyors (Master's thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca. doi:10.11575/PRISM/152
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