公开(公告)号：US20040145410A1

公开(公告)日：2004-07-29

申请号：US10756236

申请日：2004-01-13

发明人： Alfred Selz

IPC分类号： H03F001/36 ,  H03F003/04 ,  H03F003/191 ,  H03F001/34 ,  H03F001/38

CPC分类号： H03H7/0161 ,  H03H2210/015 ,  H03H2250/00 ,  H03J5/244

摘要： In a receiver, provision is made of a tuneable switchable bandpass filter comprising a primary resonant circuit and a first secondary resonant circuit. A second secondary resonant circuit can be switched into a part of the first primary resonant circuit, thereby producing a second primary resonant circuit. By virtue of the embodiment of the primary resonant circuit, the bandpass filter is switchable in terms of frequency range with little outlay on circuitry and, on account of the individual embodiment of a first and second secondary resonant circuit with individual coupling elements, can be optimized with regard to a constant amplitude response.

公开(公告)号：US20030184386A1

公开(公告)日：2003-10-02

申请号：US10306212

申请日：2002-11-27

申请人： Texas Instruments Incorporated

发明人： Alan L. Varner ,  Ahmad Dashtestani ,  Joel M. Halbert ,  Michael A. Steffes

IPC分类号： H03F001/38

CPC分类号： H03F3/45112 ,  H03F3/45139 ,  H03F3/45174

摘要： A low power current feedback amplifier having a lower output impedance input stage is provided. To reduce the output impedance, an input stage comprises a closed-loop input buffer. An exemplary input buffer comprises a closed-loop current feedback amplifier configured within the overall current feedback amplifier, wherein the output of the input buffer corresponds to the inverting node of the overall current feedback amplifier. The closed-loop configuration of the input buffer is facilitated by the use of an internal feedback resistor coupled from an inverting input terminal of the input buffer to the output of the input buffer, which corresponds to the inverting input terminal of the overall current feedback amplifier. The closed-loop input buffer realizes a low output impedance since the loop gain reduces the output impedance of the input buffer. With a lower output impedance, the bandwidth of the current feedback amplifier becomes more independent of the gain, even at low current implementations. 1 Title:LOW POWER CURRENT FEEDBACK AMPLIFIER Inventor:Alan L. Varner Ahmad Dashtestani Joel M. Halbert Michael A. Steffes

摘要翻译： 提供具有较低输出阻抗输入级的低功率电流反馈放大器。 为了减小输出阻抗，输入级包括闭环输入缓冲器。 示例性输入缓冲器包括配置在总电流反馈放大器内的闭环电流反馈放大器，其中输入缓冲器的输出对应于整个电流反馈放大器的反相节点。 输入缓冲器的闭环配置通过使用从输入缓冲器的反相输入端耦合到输入缓冲器的输出的内部反馈电阻来实现，其对应于整个电流反馈放大器的反相输入端 。 闭环输入缓冲器实现了低输出阻抗，因为环路增益降低了输入缓冲器的输出阻抗。 具有较低的输出阻抗，即使在低电流实现下，电流反馈放大器的带宽变得更加独立于增益。

公开(公告)号：US20030052732A1

公开(公告)日：2003-03-20

申请号：US09925176

申请日：2001-08-08

发明人： Philip D. Shapiro

IPC分类号： H03F001/38

CPC分类号： H03F1/38

摘要： A signal processing circuit using positive feedback while keeping the open loop gain of the circuit less than 1 to avoid oscillation. The circuit includes a floating signal source, a low gain amplifier, a feedback element, and a second stage circuit. The floating signal source produces a voltage that is impressed across the feedback element by the feedback system. The feedback element processes the voltage into an output current. The output current is passed through an output current node to the second stage circuit where the output current can be used as a current reference or be further processed. The output from the low gain amplifier may be used as a voltage output node that provides a voltage that is an amplification of the voltage produced by the floating signal source. The signal processing circuit may be embedded in another circuit, including additional stages of the signal processing circuit.

摘要翻译： 使用正反馈的信号处理电路，同时保持电路的开环增益小于1，以避免振荡。 该电路包括浮动信号源，低增益放大器，反馈元件和第二级电路。 浮动信号源产生通过反馈系统在反馈元件上施加的电压。 反馈元件将电压处理成输出电流。 输出电流通过输出电流节点传递到第二级电路，其中输出电流可以用作电流参考值或被进一步处理。 来自低增益放大器的输出可以用作提供作为放大浮动信号源产生的电压的电压的电压输出节点。 信号处理电路可以嵌入在另一个电路中，包括信号处理电路的附加级。

公开(公告)号：US20020014919A1

公开(公告)日：2002-02-07

申请号：US09902216

申请日：2001-07-10

发明人： Guido Eduard De Vrieze ,  Dirk Wouter Johannes Groeneveld

IPC分类号： H03F001/38

CPC分类号： H03F1/086

摘要： An electrical circuit arrangement (19), comprising an output stage (4) having an output terminal (2) for delivering an output current, and at least one feedback circuit (15, 16) operatively connected to the output terminal (2). A current generator circuit (20), arranged for generating a current which is a fraction of the output current, connects by a resistive element (21) to the output terminal (2), thereby providing improved high frequency feedback stability.