Title :
A CMOS Low-Distortion Variable Gain Amplifier with Exponential Gain Control
Author :
Yin, Li ; Yun, Ting-Hua ; Wu, Jian-Hui ; Shi, Long-xing
Author_Institution :
Southeast Univ. Nanjing, Nanjing
Abstract :
In this paper, a CMOS low-distortion variable gain amplifier with exponential gain control is developed by utilizing a transconductance linearization scheme. The VGA is composed of a VGA core based on current-steering structure, an exponential voltage generator based on transfer characteristics of differential pair, and a stage of fixed gain amplifier. The proposed VGA circuit was verified in 0.25 mum CMOS technology, the measurement results show a total gain control range of 40 dB, the 3-dB bandwidth is 100 MHz, and a -58.5dBc third-order inter-modulation distortion at differential output of 2 Vpp are obtained, the noise figure at maximum gain is 8.6 dB.
Keywords :
CMOS analogue integrated circuits; differential amplifiers; gain control; intermodulation distortion; linearisation techniques; CMOS low-distortion amplifier; current-steering; differential pair; exponential gain control; exponential voltage generator; fixed gain amplifier; noise figure 8.6 dB; size 0.25 mum; third-order inter-modulation distortion; transconductance linearization; variable gain amplifier; voltage 2 V; CMOS technology; Character generation; Circuits; Differential amplifiers; Distortion measurement; Gain control; Gain measurement; Noise measurement; Transconductance; Voltage;
Conference_Titel :
Solid-State Circuits Conference, 2006. ASSCC 2006. IEEE Asian
Conference_Location :
Hangzhou
Print_ISBN :
0-7803-9734-7
Electronic_ISBN :
0-7803-97375-5
DOI :
10.1109/ASSCC.2006.357929
