FEEDBACK ANALYSIS OF TRANSIMPEDANCE OPERATIONAL-AMPLIFIER CIRCUITS

被引：32

作者：

BRUUN, E

机构：

[1] Electronics Institute, Technical University of Denmark, DK-2800, Lyngby

来源：

IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS I-FUNDAMENTAL THEORY AND APPLICATIONS | 1993年 / 40卷 / 04期

关键词：

D O I：

10.1109/81.224302

中图分类号：

TM [电工技术]; TN [电子技术、通信技术];

学科分类号：

0808 ; 0809 ;

摘要：

The transimpedance or current feedback operational amplifier (CFB op-amp) is reviewed and compared to a conventional voltage mode op-amp using an analysis emphasizing the basic feedback characteristics of the circuit. With this approach the paradox of the constant bandwidth obtained from CFB op-amps is explained. It is demonstrated in a simple manner that the constant gain-bandwidth product of the conventional op-amp and the constant bandwidth of the CFB op-amp are both in accordance with basic feedback theory and that the differences between the traditional op-amp and the CFB op-amp are due to different ways of controlling the closed-loop gain. For the traditional op-amp the closed-loop gain is altered by altering the loop gain whereas the closed-loop gain in a CFB op-amp configuration is altered by altering the input attenuation to the feedback loop while maintaining a constant-loop gain.

引用

页码：275 / 278

页数：4