半导体学报2009，Vol.30Issue(6)：111-115,5.DOI:10.1088/1674-4926/30/6/065006
A 60-dB linear VGA with novel exponential gain approximation
A 60-dB linear VGA with novel exponential gain approximation
Zhou Jiaye 1Tan Xi 1Wang Junyu 1Tang Zhangwen 1Min Hao1
作者信息
- 1. State Key Laboratory of ASIC & System,Fudan University,Shanghai 201203,China
- 折叠
摘要
Abstract
A CMOS variable gain amplifier (VGA) that adopts a novel exponential gain approximation is presented.No additional exponential gain control circuit is required in the proposed VGA used in a direct conversion receiver.A wide gain control voltage from 0.4 to 1.8 V and a high linearity performance are achieved. The three-stage VGA with automatic gain control (AGC) and DC offset cancellation (DCOC) is fabricated in a 0.18-μm CMOS technology and shows a linear gain range of more than 58-dB with a linearity error less than ± 1 dB. The 3-dB bandwidth is over 8 MHz at all gain settings. The measured input-referred third intercept point (IIP3) of the proposed VGA varies from -18.1 to 13.5 dBm, and the measured noise figure varies from 27 to 65 dB at a frequency of 1 MHz. The dynamic range of the closed-loop AGC exceeds 56 dB, where the output signal-to-noise-and-distortion ratio (SNDR) reaches 20 dB. The whole circuit, occupying 0.3 mm2 of chip area, dissipates less than 3.7 mA from a 1.8-V supply.关键词
variable gain amplifier/dB-linear/auto gain control/direct conversion receiverKey words
variable gain amplifier/dB-linear/auto gain control/direct conversion receiver分类
信息技术与安全科学引用本文复制引用
Zhou Jiaye,Tan Xi,Wang Junyu,Tang Zhangwen,Min Hao..A 60-dB linear VGA with novel exponential gain approximation[J].半导体学报,2009,30(6):111-115,5.
