On the effect of time delays in negative feedback amplifiers

• Author(s): Alves, L. N. ; Aguiar, R.L.
• Date: 2012
• Persistent ID: http://hdl.handle.net/10773/5211
• Origin: RIA - Repositório Institucional da Universidade de Aveiro
• Subject(s): Bandwidth enhancement; Bandwidth extension; Delay elements; Feedback paths; Loop gains; Negative feedback amplifier; Open loops; Shunt configuration; Delay circuits; Electric cables; Feedback; Feedback amplifiers; Frequency response; Telecommunication cables; Time delay
• Document Type: Conference Object
• Language: English

Description

Time delays are intrinsic to all existing devices and circuits. For the majority of applications, time delays are so small that their effects can be disregarded. However, when considering feedback amplifiers, depending on open-loop poles and loop gain, the effect of a small time delay inside the feedback path may turn to be of considerable importance. This paper analyzes the frequency response effects associated with time delays in feedback amplifiers, exploiting these effects to achieve bandwidth enhancements. An illustration of this effect is presented using a TL082 in series-shunt configuration, attaining 100% bandwidth extension, when associated with a 36m length RG58 coaxial cable as delay element. © 2005 IEEE.