Title :
Constant and maximum bandwidth feedback amplifier with adaptive frequency compensation
Author :
Pennisi, Salvatore ; Scotti, Giuseppe ; Trifiletti, Alessandro
Author_Institution :
Dipt. di Ing. Elettr., Elettron. e Inf. (DIEEI), Univ. di Catania, Catania, Italy
Abstract :
We demonstrated the feasibility of the adaptive frequency compensation approach to design maximum- and constant-bandwidth feedback amplifiers. A basic CMOS amplifier exhibiting 66-dB dc gain and 310-MHz gain-bandwidth product was designed. For closed-loop gains ranging from 1 to 10, the closed loop bandwidth was found never lower than 401 MHz. A similar amplifier with equal gain-bandwidth product, but adopting the traditional fixed compensation approach, would exhibit a closed-loop bandwidth decreased to 33 MHz when the gain magnitude is set to 10. The enhanced frequency performance is obtained with a 48% increase in current consumption, while the other main opamp performance parameters remain almost unchanged compared to the standard solution.
Keywords :
CMOS integrated circuits; closed loop systems; compensation; feedback amplifiers; operational amplifiers; CMOS amplifier; adaptive frequency compensation; bandwidth 310 MHz; closed loop bandwidth; closed-loop gains; constant bandwidth; equal gain-bandwidth product; feedback amplifier; fixed compensation; gain 66 dB; maximum bandwidth; opamp performance parameters; Bandwidth; CMOS integrated circuits; Capacitors; Gain; Operational amplifiers; Resistors; Transistors;
Conference_Titel :
Circuits and Systems (ISCAS), 2012 IEEE International Symposium on
Conference_Location :
Seoul
Print_ISBN :
978-1-4673-0218-0
DOI :
10.1109/ISCAS.2012.6272057
