公开(公告)号：US20020039049A1

公开(公告)日：2002-04-04

申请号：US09918557

申请日：2001-08-01

申请人： IWATSU ELECTRIC CO., LTD.

发明人： Atsushi Minegishi

IPC分类号： H03F003/45

CPC分类号： H03F3/45511 ,  H03F3/45085 ,  H03F2203/45392 ,  H03F2203/45418 ,  H03F2203/45566 ,  H03F2203/45654 ,  H03F2203/45702 ,  H03F2203/45722

摘要： An amplifying circuit with a level-shift circuit is disclosed. An amplifying unit includes two stages of differential amplifiers cascadedly connected. A differential amplifier of the first stage has a pair of differential input terminals. The differential amplifier of the last stage has a pair of differential output terminals. A level-shift circuit constituted of a couple of level-shifters is connected to the output terminals. The level-shift circuit level-shifts the DC level of the differential output from the amplifying unit. The level-shift circuit has a pair of output terminals to deliver the level-shifted differential output. A DC-dummy dummies the DC operation of the differential amplifier of the last stage. The DC-dummy has the power supply in common with the differential amplifier of the last stage. A level-shifter shifts the output level from the DC-dummy and delivers the level-shifted dummy output. The constitution of the level-shifter is the same as one of a couple of level-shifters in the level-shift circuit. An operational amplifier keeps a voltage of the level-shifted dummy output constant. Therefore, the operational amplifier supplies the voltage power in common to the differential amplifier of the last stage and the DC-dummy.

摘要翻译： 公开了一种具有电平移位电路的放大电路。 放大单元包括级联的两级差分放大器。 第一级的差分放大器具有一对差分输入端子。 最后一级的差分放大器有一对差分输出端子。 由一对电平移位器构成的电平移位电路连接到输出端子。 电平移位电路使放大单元的差分输出的直流电平移位。 电平移位电路具有一对输出端子以输出电平移位的差分输出。 DC-dummy模拟最后一级的差分放大器的直流工作。 DC-dummy具有与最后一级的差分放大器相同的电源。 电平移位器将输出电平从DC-dummy移位，并传送电平移位的虚拟输出。 电平移位器的结构与电平移位电路中的一对电平移位器中的一个相同。 运算放大器保持电平移位虚拟输出的电压恒定。 因此，运算放大器将最后一级的差分放大器和DC-虚拟电路的电压电源共同提供。