一种全差分增益自举运算放大器的设计  

A Design of Fully Differential Gain Boosted Operational Amplifier

作　　者：冯文晓[1] 陆铁军[1] 王宗民[1] 周亮[1] 

机构地区：[1]北京微电子技术研究所,北京100076

出　　处：《微电子学与计算机》2010年第12期142-145,共4页Microelectronics & Computer

摘　　要：设计实现了一种具有高增益大带宽的全差分增益自举运算放大器,适用于高速高精度流水线模数转换器采保电路的应用.增益自举放大器的主放大器和子放大器均采用折叠共源共栅式全差分结构,并且主放大器采用开关电容共模反馈来稳定输出电压.该放大器工作在3.0 V电源电压下,单端负载为2pF,采用0.18μm CMOS工艺库对电路进行仿真,结果显示该放大器的直流增益可达到112dB,单位增益带宽为1.17GHz.In this paper,a high gain and high speed fully differential gain boosted operational amplifier is proposed.The amplifier is designed for sample and hold circuit of pipelined analog-to-digital converter.Both the main amplifier and the boosted amplifier adopt fully differential folded-cascode structure.The main amplifier uses a switched capacitance common mode feedback circuit to stabilize the output.With 3.0 V power supply,this circuit is designed in 0.18μm CMOS process.Spectre simulation shows that the whole amplifier has the DC gain of 112 dB and the unity gain bandwidth of 1.17 GHz under 2 pF single ended load.

关 键 词：全差分放大器 增益自举 折叠共源共栅 采保电路 

分 类 号：TN47[电子电信—微电子学与固体电子学]