Conference Paper

A simple approach for the implementation of CMOS amplifiers with constant bandwidth independent of gain.

Dept. of Electron. Eng., Univ. of Seville, Seville
DOI: 10.1109/ISCAS.2008.4541412 Conference: International Symposium on Circuits and Systems (ISCAS 2008), 18-21 May 2008, Sheraton Seattle Hotel, Seattle, Washington, USA
Source: DBLP

ABSTRACT In this paper we discuss an efficient implementation of the Cherry-Hooper amplifier scheme based on a new OTA structure. This is used to design highly linear CMOS amplifiers with programmable and accurate gain and high bandwidth that remains approximately constant with gain adjustment. A fully differential VGA with 30 MHz approximate constant bandwidth and accurate digitally adjustable gain from 1 to 128 in 0.5 mum CMOS technology is discussed. Experimental verification of the proposed scheme is also provided.

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