Title :
A 120dB all CMOS variable gain amplifier based on new exponential equation
Author :
Sheikhhosseini, Farhad ; Nabavi, Abdolreza
Author_Institution :
Fac. of Electr. & Comput. Eng., Tarbiat Modares Univ., Tehran, Iran
Abstract :
This paper presents the design of a two-stage wide dynamic range variable gain amplifier (VGA). This is based on a new approximated exponential equation which offers a wide decibel linear range and an improved fully differential MOS Cherry-Hooper topology. In addition, the bandwidth of the VGA has been extended by using the capacitive neutralization technique for wide-band applications. Simulation results based on a 0.13-μm CMOS technology demonstrate that the gain variation range of the VGA is 120dB (from -79 ~ 41 dB) when control voltage changes from -0.8V to 0.8V. The -3dB bandwidth of the VGA at the maximum gain is 132MHz and the overall current consumption is 3.34mA if the Vdd=1.2V and the Vss=-1.2V.
Keywords :
CMOS analogue integrated circuits; amplifiers; network topology; CMOS variable gain amplifier; approximated exponential equation; capacitive neutralization technique; current 3.34 mA; frequency 132 MHz; fully differential MOS Cherry-Hooper topology; gain 120 dB; size 0.13 mum; voltage -0.8 V to 0.8 V; voltage 1.2 V; wide-band application; Approximation methods; Bandwidth; CMOS integrated circuits; Computer architecture; Gain; Microprocessors; Transistors; Cherry-Hooper amplifier; Variable gain amplifier (VGA); control function; current squarer; dB-linear characteristics;
Conference_Titel :
Circuits and Systems (APCCAS), 2010 IEEE Asia Pacific Conference on
Conference_Location :
Kuala Lumpur
Print_ISBN :
978-1-4244-7454-7
DOI :
10.1109/APCCAS.2010.5774738
