公开(公告)号：EP1713178A1

公开(公告)日：2006-10-18

申请号：EP05425223.4

申请日：2005-04-14

Applicant: STMicroelectronics S.r.l. ,  STMicroelectronics S.A.

Inventor： Chiricosta, Mario ,  Sirito-Olivier, Philippe

IPC: H03G1/00

CPC classification number: H03G1/0023

Abstract: A variable-gain amplifier includes an amplifier stage (17); an attenuating network (14a, 14b) receiving an input signal (V I ) ; a plurality of transconductance stages (15), connected between respective nodes (14a1, 14a2, ..., 14aN, 14b1, 14b2, ..., 14bN) of the attenuating network (14a, 14b) and the amplifier stage (17), wherein each of the transconductance stages (15) has a differential circuit (20), configured to supply differential currents (I D1 , I D2 ) to the amplifier stage (17); and a gain-control circuit (16) for controlling the transconductance stages (15) according to an electrical control quantity (V c ). Each of the transconductance stages (15) further includes a current-divider circuit (21) associated to the differential circuit (20) and controlled by the gain-control circuit (16) so as to divide the differential currents (T D1 , T D2 ) between the amplifier stage (17) and a dispersion line (33) proportionally to the control quantity (V C ).

Abstract translation: 一种可变增益放大器包括放大器级（17）; 在衰减网络（14A，14B）处接收输入信号（V I）; 连接在衰减网络的respectivement节点（14A1，14A2，...，14aN，14B1，14B2，...，140亿）之间跨导级的多个（15）（14A，14B）和所述放大级（17） ，worin每个跨导级（15）具有被配置为提供差动电流（I D1，我D2）到所述放大级（17）的差动电路（20）; 和用于在电控制量（V c）控制的跨导级（15）雅丁到增益控制电路（16）。 每个跨导级（15）还包括由所述增益控制电路（16）关联到所述差动电路（20）和控制的电流分压器电路（21），以便划分差动电流（I D1，我D2 ）所述放大级（17）和一个分散线（33）成比例的控制量（VC）之间。