公开(公告)号：EP1548932A1

公开(公告)日：2005-06-29

申请号：EP03079182.6

申请日：2003-12-24

Applicant: STMicroelectronics Belgium N.V.

Inventor： Joos, Dieter ,  Borremans, Marc

IPC: H03F3/45

CPC classification number: H03F3/45179 ,  H03F3/189 ,  H03F2200/294 ,  H03F2200/372 ,  H03F2203/45306 ,  H03F2203/45318

Abstract: A low noise differential amplifier has a pair of single ended common-gate or common-base circuits and cross coupling of an input of one of the pair to the gate or base of the other one of the pair. This cross-coupling puts the differential input voltage over the Gate-Source of the common-gate transistor (or Base-Emitter of the common base transistor). This means that the same input impedance and gain can be made with half the current compared to a basic common-gate topology. The cross-coupling means the noise generated by the positive side of the common-gate structure ends up partly on the negative output and vice versa, and so the Noise Figure can be less than 3dB.

Abstract translation: 低噪声差分放大器具有一对单端公共栅极或公共基极电路，并且该对中的一个的输入与该对中的另一个的栅极或基极交叉耦合。 这种交叉耦合将差分输入电压放在公共栅极晶体管（或公共基极晶体管的基极 - 发射极）的栅极 - 源极上。 这意味着与基本公共门拓扑相比，可以以一半的电流进行相同的输入阻抗和增益。 交叉耦合意味着由共栅结构的正侧产生的噪声部分地在负输出端反而相反，因此噪声系数可以小于3dB。