东南大学学报（英文版）2017，Vol.33Issue(2)：134-139,6.DOI:10.3969/j.issn.1003-7985.2017.02.002
带有二进制开关和恒跨导偏置的信号求和型可编程增益放大器
A signal-summing programmable gain amplifier employing binary-weighted switching and constant-gm bias
摘要
Abstract
A novel programmable gain amplifier(PGA)based on a signal-summing topology is proposed.Different from conventional signal-summing variable gain amplifiers(VGA),a binary-weighted switching technique is employed to vary the current-steering transistors' aspect ratio to change their transconductance,and hence,an accurate gain step size of 6 dB is achieved.The constant-gm biasing technique and the matching of the transistors and resistors ensures that the gain of the proposed topology is independent of the variation of process,voltage and temperature(PVT).P-well NMOS(N-metal oxide semiconductor)transistors are utilized to eliminate the influence of back-gate effect which will induce gain error.The source-degeneration technique ensures good linearity performance at a low gain.The proposed PGA is fabricated in a 0.18 μm CMOS(complementary metal oxide semiconductor)process.The measurement results show a variable gain ranging from 0 to 24 dB with a step size of 6 dB and a maximum gain error of 0.3 dB.A constant 3 dB bandwidth of 210 MHz is achieved at different gain settings.The measured output 3rd intercept point(OIP3)and minimum noise figure(NF)are 20.9 dBm and 11.1 dB,respectively.The whole PGA has a compact layout of 0.068 mm2.The total power consumption is 4.8 mW under a 1.8 V supply voltage.关键词
可编程增益放大器/可变增益放大器/信号求和结构/恒跨导偏置Key words
programmable gain amplifier/variable gain amplifier/signal-summing topology/constant-gm分类
信息技术与安全科学引用本文复制引用
马力,王志功,徐建..带有二进制开关和恒跨导偏置的信号求和型可编程增益放大器[J].东南大学学报（英文版）,2017,33(2):134-139,6.基金项目
The National Natural Science Foundation of China(No.61306069). （No.61306069）
