2 research outputs found
Precizni dvostrani usmerivaÄi malih signala realizovani u tehnici strujnog procesiranja
REZIME:
Obrada analognih signala moĆŸe se izvoditi u tehnici naponskog ili strujnog
procesiranja. Iako je naponsko procesiranje imalo dominantniju ulogu u obradi
signala dugi niz godina, pojavom strujnih prenosnika, strujno procesiranje dobija na
znaÄaju u poslednjih dvadesetak godina zbog viĆĄe svojih prednosti koje su dokazane na
primerima preciznih dvostranih usmeraÄa za male signale obraÄenih i u ovoj tezi. Pre
svega prednost se ogleda u poveÄanju ĆĄirine propusnog opsega zbog upotrebe
optereÄenja male impedanse.
Predmet disertacije je realizacija preciznih dvostranih usmeraÄa za signale
malih amplituda u tehnici strujnog procesiranja. Precizno usmeravanje je vaĆŸna
funkcija obrade signala koja ima izuzetnu vaĆŸnost kod mnogih mernih ureÄaja kao ĆĄto
su voltmetri i ampermetri za naizmeniÄne signale, detektori polariteta signala,
detektori vrĆĄne vrednosti, detektori amplitudno-modulisanih signala, kola za
usrednjavanje signala itd..
Nakon opisa tehnike strujnog procesiranja i prikaza translinearnog principa,
kao polazne osnove za realizaciju brojnih nelinearnih kola u bipolarnoj tehnologiji,
razmatran je koncept strujnog prenosnika sa posebnim osvrtom na strujnom prenosniku
druge vrste sa bipolarnim tranzistorima. Opisan je i koncept operacionog
prenosnika, a sa posebnom paĆŸnjom obraÄen je operacioni prenosnik druge vrste sa
strujnim kormilarenjem. Dat je i prikaz uporedne analize preciznih dvostranih
usmeraÄa realizovanih u tehnici naponskog procesiranja kao i u tehnici strujnog
procesiranja, sa prednostima i manama jednih u odnosu na druge.
U disertaciji su predstavljena dva modela preciznog dvostranog usmeraÄa za
male signale, od kojih prvi model koristi operacioni prenosnik, Äetiri strujna
ogledala i dva strujna izvora, dok je drugi model realizovan sa dva operaciona
prenosnika i dve diode sa predpolarizacijom. Osobine realizovanih usmeraÄa su
znatno bolje u odnosu na usmeraÄe realizovane sa istim elektronskim komponentam u
tehnici naponskog procesiranja. Kroz simulacionu i eksperimentalnu proveru
dokazano je da je moguÄe realizovati precizni dvostrani usmeraÄ u tehnici strujnog
procesiranja koji radi u ĆĄirokom frekventnom opsegu, za signale male amplitude,
upotrebom dve diode umesto Äetiri, kako je to do sada uglavnom raÄeno. TakoÄe je
pokazano da ovakav usmeraÄ ima sve bitne osobine bolje od osobina usmeraÄa
realizovanog u tehnici naponskog procesiranja.SUMMARY:
The processing of analog signals can be performed in the voltage or current processing
technique. Although the voltage processing has had a more dominant role in signal processing
for many years, with the adventages of current conveyors, current processing has become more
important over the past twenty years due to its manifold advantages, which have been proved
by examples of precision full wave rectifiers for small signals dealt with in this thesis. The first
advantage is the in increase of the bandwidth due to the use of a small impedance load.
The subject of the doctoral thesis is the realization of full-wave rectifier for small
amplitude signals in a current mode processing techniques. Precise rectification is an important
function of signal processing and it is highly significant in many measuring devices, such as
voltmeters, ammeters for alternating signals, detectors, signal polarity detectors, peak
detectors, amplitude-modulated signal detectors, averaging circuits, etc...
The dissertation presents the description of a current processing technique and
translinear principle as an initial point for the realization of numerous nonlinear circuits in
bipolar technology. This is followed by a speculation on a concept of current conveyor, where
a special focus is placed on a different type of current conveyor with bipolar transistors. In
addition, the concept of operational conveyor is given with an emphasis on a different type of
operational conveyor with current steering output stage. The thesis also presents a comparative
analysis of full-wave rectifiers, which are realized in both, voltage and current processing
techniques, as well as their advantages and disadvantages compared to each other.
The dissertation presents two models of precision full-wave rectifier for low-level
signals, as well as the realization of the rectifiers out of which one uses an operational conveyor
and four current mirrors and two direct current sources, while another one has two operational
conveyors and two diodes with polarization before of them. The characteristics of such
rectifiers are significantly better compared to the rectifiers with the same electronic
components in voltage processing technique. Through simulation and experimental verification
it has been proved that the full-wave rectifier in a current processing technique can be realized
for wide frequency range, for low amplitude signals, by using two diodes instead of four, as it
has been mostly done so far. It was also shown that such rectifiers have better characteristics
than the rectifiers realized in voltage processing mode
Low Voltage Low Power Analogue Circuits Design
DisertaÄnĂ prĂĄce je zamÄĆena na vĂœzkum nejbÄĆŸnÄjĆĄĂch metod, kterĂ© se vyuĆŸĂvajĂ pĆi nĂĄvrhu analogovĂœch obvodĆŻ s vyuĆŸitĂ nĂzkonapÄĆ„ovĂœch (LV) a nĂzkopĆĂkonovĂœch (LP) struktur. Tyto LV LP obvody mohou bĂœt vytvoĆeny dĂky vyspÄlĂœm technologiĂm nebo takĂ© vyuĆŸitĂm pokroÄilĂœch technik nĂĄvrhu. DisertaÄnĂ prĂĄce se zabĂœvĂĄ prĂĄvÄ pokroÄilĂœmi technikami nĂĄvrhu, pĆedevĆĄĂm pak nekonvenÄnĂmi. Mezi tyto techniky patĆĂ vyuĆŸitĂ prvkĆŻ s ĆĂzenĂœm substrĂĄtem (bulk-driven - BD), s plovoucĂm hradlem (floating-gate - FG), s kvazi plovoucĂm hradlem (quasi-floating-gate - QFG), s ĆĂzenĂœm substrĂĄtem s plovoucĂm hradlem (bulk-driven floating-gate - BD-FG) a s ĆĂzenĂœm substrĂĄtem s kvazi plovoucĂm hradlem (quasi-floating-gate - BD-QFG). PrĂĄce je takĂ© orientovĂĄna na moĆŸnĂ© zpĆŻsoby implementace znĂĄmĂœch a modernĂch aktivnĂch prvkĆŻ pracujĂcĂch v napÄĆ„ovĂ©m, proudovĂ©m nebo mix-mĂłdu. Mezi tyto prvky lze zaÄlenit zesilovaÄe typu OTA (operational transconductance amplifier), CCII (second generation current conveyor), FB-CCII (fully-differential second generation current conveyor), FB-DDA (fully-balanced differential difference amplifier), VDTA (voltage differencing transconductance amplifier), CC-CDBA (current-controlled current differencing buffered amplifier) a CFOA (current feedback operational amplifier). Za ĂșÄelem potvrzenĂ funkÄnosti a chovĂĄnĂ vĂœĆĄe zmĂnÄnĂœch struktur a prvkĆŻ byly vytvoĆeny pĆĂklady aplikacĂ, kterĂ© simulujĂ usmÄrĆovacĂ a induktanÄnĂ vlastnosti diody, dĂĄle pak filtry dolnĂ propusti, pĂĄsmovĂ© propusti a takĂ© univerzĂĄlnĂ filtry. VĆĄechny aktivnĂ prvky a pĆĂklady aplikacĂ byly ovÄĆeny pomocĂ PSpice simulacĂ s vyuĆŸitĂm parametrĆŻ technologie 0,18 m TSMC CMOS. Pro ilustraci pĆesnĂ©ho a ĂșÄinnĂ©ho chovĂĄnĂ struktur je v disertaÄnĂ prĂĄci zahrnuto velkĂ© mnoĆŸstvĂ simulaÄnĂch vĂœsledkĆŻ.The dissertation thesis is aiming at examining the most common methods adopted by analog circuits' designers in order to achieve low voltage (LV) low power (LP) configurations. The capability of LV LP operation could be achieved either by developed technologies or by design techniques. The thesis is concentrating upon design techniques, especially the nonâconventional ones which are bulkâdriven (BD), floatingâgate (FG), quasiâfloatingâgate (QFG), bulkâdriven floatingâgate (BDâFG) and bulkâdriven quasiâfloatingâgate (BDâQFG) techniques. The thesis also looks at ways of implementing structures of wellâknown and modern active elements operating in voltageâ, currentâ, and mixedâmode such as operational transconductance amplifier (OTA), second generation current conveyor (CCII), fullyâdifferential second generation current conveyor (FBâCCII), fullyâbalanced differential difference amplifier (FBâDDA), voltage differencing transconductance amplifier (VDTA), currentâcontrolled current differencing buffered amplifier (CCâCDBA) and current feedback operational amplifier (CFOA). In order to confirm the functionality and behavior of these configurations and elements, they have been utilized in application examples such as diodeâless rectifier and inductance simulations, as well as lowâpass, bandâpass and universal filters. All active elements and application examples have been verified by PSpice simulator using the 0.18 m TSMC CMOS parameters. Sufficient numbers of simulated plots are included in this thesis to illustrate the precise and strong behavior of structures.