Abstract
This paper presents a novel adaptive bias technique based on the use of squaring circuits. Here, the tail current of an operational amplifier (OpAmp) is controlled using an auxiliary circuit. By design, it generates a well-controlled tail current which — to a first order approximation — is independent of the OpAmp's common-mode input voltage. As a result, parameters like common-mode rejection ratio (CMRR) and power supply rejection ratio (PSRR) are enhanced. However, when a differential input signal is applied, it generates a tail current proportional to the square of the OpAmp's differential input voltage. In this way, the currents of the OpAmp's input pairs are boosted, thus improving slew rate. Experimental results in 0.5 μm CMOS technology verify current and slew rate enhancement factors between 10 and 15 with less than 20% static current increase.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
