<abstract xmlns="http://www.w3.org/1999/xhtml"><p>The paper deals with precise analysis of simple AC variable gain CMOS amplifier. The circuit can be used as a simple voltage follower (6 MOS transistors are required) or amplifier. The main attention of this work is focused on a small-signal model of the proposed block and effects of additional passive network leading to compensation of its instability. The continuous gain adjusting in range from 1.1 to 10 (0.8 – 20 dB and with bandwidth 4.9 - 90 MHz at 5 pF load capacitance) is possible and the proposed amplifier is suitable for implementation in systems, where lower range of gain adjusting and large dynamical range is required. Theoretical analyses are supported by PSpice simulations (TSMC 0.18 um technological models) and experimental measurements with commercially available CMOS transistor fields (ALD1106/7) also confirm the discussed behavior of the amplifier.</p></abstract>

The paper deals with precise analysis of simple AC variable gain CMOS amplifier. The circuit can be used as a simple voltage follower (6 MOS transistors are required) or amplifier. The main attention of this work is focused on a small-signal model of the proposed block and effects of additional passive network leading to compensation of its instability. The continuous gain adjusting in range from 1.1 to 10 (0.8 – 20 dB and with bandwidth 4.9 - 90 MHz at 5 pF load capacitance) is possible and the proposed amplifier is suitable for implementation in systems, where lower range of gain adjusting and large dynamical range is required. Theoretical analyses are supported by PSpice simulations (TSMC 0.18 um technological models) and experimental measurements with commercially available CMOS transistor fields (ALD1106/7) also confirm the discussed behavior of the amplifier.

Study of Small-signal Model of Simple CMOS Amplifier with Instability Compensation of Positive Feedback Loop

Dept. of Radio Electronics, Faculty of Electrical Engineering and Communication, Brno University of Technology, Technicka 3082/12, 61600, Brno, Czech Republic

Dept. of Telecommunications, Faculty of Electrical Engineering and Communication, Brno University of Technology, Technicka 3082/12, 61600, Brno, Czech Republic

D3-Friends Apartments, IP Extension, Delhi, India

Dept. of Electrical Engineering and Computer Science, College of Polytechnics Jihlava, Jihlava, Tolsteho 16, 586 01, Czech Republic

Measurement Science Review

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

The paper deals with precise analysis of simple AC variable gain CMOS amplifier. The circuit can be used as a simple voltage follower (6 MOS transistors are...

Study of Small-signal Model of Simple CMOS Amplifier with Instability Compensation of Positive Feedback Loop

Published Online: Jul 10, 2015

Page range: 139 - 151

Received: Nov 26, 2014

Accepted: Jun 26, 2015

DOI: https://doi.org/10.1515/msr-2015-0021

Keywords
Active elements, instability compensation, variable gain amplifier, voltage buffer, voltage follower, voltage gain adjusting

© R. Sotner et al.

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Study of Small-signal Model of Simple CMOS Amplifier with Instability Compensation of Positive Feedback Loop

Published Online: Jul 10, 2015

Page range: 139 - 151

Received: Nov 26, 2014

Accepted: Jun 26, 2015

DOI: https://doi.org/10.1515/msr-2015-0021

KeywordsActive elements, instability compensation, variable gain amplifier, voltage buffer, voltage follower, voltage gain adjusting

© R. Sotner et al.

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Keywords
Active elements, instability compensation, variable gain amplifier, voltage buffer, voltage follower, voltage gain adjusting