Title :
Zero-IF VGA with novel offset cancellation
Author :
Yang, Chao ; Mason, Andrew
Author_Institution :
Dept. of Electr. & Comput. Eng., Michigan State Univ., East Lansing, MI
Abstract :
Reliable offset control is a vital feature of a zero-IF variable gain amplifier (VGA). Many traditional methods sacrifice speed (settling time) to achieve offset control by realizing a high pass feature in the signal path. This paper introduces a novel VGA architecture that is capable of controlling offset for all gain settings with a single offline calibration cycle. The VGA realizes very fast gain/startup settling time with only a slight increase in power and area requirements by eliminating the need for a high pass filter. The VGA circuit draws 3mA and has a gain range of 0~42dB with 1dB steps. It has a 10MHz bandwidth at 42dB, has a gain settling time of 140nsec, and controls output offset within 2.2mV
Keywords :
CMOS integrated circuits; gain control; integrated circuit design; intermediate-frequency amplifiers; operational amplifiers; 0 to 42 dB; 10 MHz; 140 ns; 2.2 mV; 3 mA; VGA circuit; high pass filter; offline calibration cycle; offset control; zero-IF variable gain amplifier; Calibration; Chaos; Circuits; Cutoff frequency; Dynamic range; Electric variables control; Filters; Gain; Transceivers; Voltage control;
Conference_Titel :
Circuits and Systems, 2006. ISCAS 2006. Proceedings. 2006 IEEE International Symposium on
Conference_Location :
Island of Kos
Print_ISBN :
0-7803-9389-9
DOI :
10.1109/ISCAS.2006.1693365