Publication detail

Realization of Current-Mode KHN-Equivalent Biquad Using Current Follower Transconductance Amplifiers (CFTAs)

HERENCSÁR, N. KOTON, J. VRBA, K.

Original Title

Realization of Current-Mode KHN-Equivalent Biquad Using Current Follower Transconductance Amplifiers (CFTAs)

Czech Title

Realization of Current-Mode KHN-Equivalent Biquad Using Current Follower Transconductance Amplifiers (CFTAs)

English Title

Realization of Current-Mode KHN-Equivalent Biquad Using Current Follower Transconductance Amplifiers (CFTAs)

Type

journal article

Language

en

Original Abstract

In this letter a new active element the Current Follower Transconductance Amplifier (CFTA) for the realization of the current-mode analog blocks is presented. The element is a combination of the Current Follower (CF) and the Balanced Output Transconductance Amplifier (BOTA). Possible internal structure of the CFTA is presented. The usage of the new active element is shown on the design of the Kerwin-Huelsman-Newcomb (KHN) structure working in the current mode. The frequency filter using the CFTA elements has been designed using the signal-flow graphs. The circuit structure employs three CFTA elements and two grounded passive elements. The filter enables realizing not only the basic functions as the low- (LP), band- (BP) and high-pass (HP) but also the notch and all-pass (AP) filter. The advantage of the structure presented is that the outputs of the filter are at high impedance and hence it is not necessary to use other auxiliary active elements. The properties of the filter proposed were verified by sensitivity and AC analyses in the PSPICE program.

Czech abstract

V tomto dopisu je presentován nový aktivní prvek Current Follower Transconductance Amplifier (CFTA) vhodný pro realizaci analogových bloků pracujících v proudovém módu. Prvek vznikl kombinací Current Follower (CF) a Balanced Output Transconductance Amplifier (BOTA). Je uvedena navržená vnitřní struktura prvku CFTA na tranzistorové úrovni. Využití uváděného aktivního prvku je presentováno na realizaci známé struktury Kerwin-Huelsman-Newcomb (KHN) pracující v proudovém módu. Nové zapojení s prvky CFTA byla navřena pomocí grafů signálových toků vycházející z původní struktury s operačními zesilovači. Obvodová struktura filtru se skládá ze tří aktivních prvků CFTA a dvou uzemněných pasivních prvků. Filtr umožňuje realizovat nejen základní filtrační funkce dolní (LP), pásmová (BP) a horní propust (HP) ale i pásmovou zádrž (notch) a fázovací článek (AP). Výhodou je, že filtry mají vysokoimpedanční proudové výstupy bez nutnosti použití dalšího aktivního prvku. Vlastnosti navrženého filtru byly podrobeny citlivostní analýze a střídavé analýze v programu PSPICE.

English abstract

In this letter a new active element the Current Follower Transconductance Amplifier (CFTA) for the realization of the current-mode analog blocks is presented. The element is a combination of the Current Follower (CF) and the Balanced Output Transconductance Amplifier (BOTA). Possible internal structure of the CFTA is presented. The usage of the new active element is shown on the design of the Kerwin-Huelsman-Newcomb (KHN) structure working in the current mode. The frequency filter using the CFTA elements has been designed using the signal-flow graphs. The circuit structure employs three CFTA elements and two grounded passive elements. The filter enables realizing not only the basic functions as the low- (LP), band- (BP) and high-pass (HP) but also the notch and all-pass (AP) filter. The advantage of the structure presented is that the outputs of the filter are at high impedance and hence it is not necessary to use other auxiliary active elements. The properties of the filter proposed were verified by sensitivity and AC analyses in the PSPICE program.

Keywords

CFTA, current-mode circuit, KHN-biquad

RIV year

2010

Released

01.10.2010

Publisher

IEICE

Location

Japonsko

Pages from

1816

Pages to

1819

Pages count

4

BibTex


@article{BUT49924,
  author="Norbert {Herencsár} and Jaroslav {Koton} and Kamil {Vrba}",
  title="Realization of Current-Mode KHN-Equivalent Biquad Using Current Follower Transconductance Amplifiers (CFTAs)",
  annote="In this letter a new active element the Current Follower Transconductance Amplifier (CFTA) for the realization of the current-mode analog blocks is presented. The element is a combination of the Current Follower (CF) and the Balanced Output Transconductance Amplifier (BOTA). Possible internal structure of the CFTA is presented. The usage of the new active element is shown on the design of the Kerwin-Huelsman-Newcomb (KHN) structure working in the current mode. The frequency filter using the CFTA elements has been designed using the signal-flow graphs. The circuit structure employs three CFTA elements and two grounded passive elements. The filter enables realizing not only the basic functions as the low- (LP), band- (BP) and high-pass (HP) but also the notch and all-pass (AP) filter. The advantage of the structure presented is that the outputs of the filter are at high impedance and hence it is not necessary to use other auxiliary active elements. The properties of the filter proposed were verified by sensitivity and AC analyses in the PSPICE program.",
  address="IEICE",
  chapter="49924",
  institution="IEICE",
  journal="IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES",
  number="10",
  volume="93",
  year="2010",
  month="october",
  pages="1816--1819",
  publisher="IEICE",
  type="journal article"
}