Title :
AGC loop implementation using temperature compensated CMOS linear-in-dB VGA
Author :
Kalenteridis, V. ; Siskos, S. ; Vlassis, S.
Author_Institution :
Phys. Dept., Aristotle Univ. of Thessaloniki, Thessaloniki, Greece
Abstract :
In this paper, an Automatic Gain Control (AGC) loop is proposed which is based on a linear-in-dB Variable Gain Amplifier (VGA). The VGA structure is based on simple nMOS differential pairs. The linear-in-dB gain tuning schema is designed using a novel exponential generator which it offers also temperature compensation of the VGA´s gain. The proposed implementation is designed in 90nm CMOS process with 1.2V supply voltage. The gain of the VGA is tuned by a control voltage with gain range equal to 27dB with ±1dB linearity error. The worst case variations of the VGA gain, over process and temperature corners, are ±1.54dB and ±2.45dB for maximum and minimum gain setting, respectively.
Keywords :
CMOS integrated circuits; automatic gain control; AGC loop implementation; CMOS process; VGA gain; automatic gain control loop; control voltage; exponential generator; linear-in-dB gain tuning schema; linear-in-dB variable gain amplifier; linearity error; maximum gain setting; minimum gain setting; nMOS differential pairs; temperature compensated CMOS linear-in-dB VGA structure; temperature compensation; Automatic generation control; CMOS integrated circuits; Gain; Generators; Temperature; Transistors; Voltage control; AGC loop; CMOS linear-in-dB VGA; exponential current generator;
Conference_Titel :
Instrumentation and Measurement Technology Conference (I2MTC), 2012 IEEE International
Conference_Location :
Graz
Print_ISBN :
978-1-4577-1773-4
DOI :
10.1109/I2MTC.2012.6229368
