公开(公告)号：US5610564A

公开(公告)日：1997-03-11

申请号：US140233

申请日：1993-10-20

申请人： Luciano Tomasini ,  Rinaldo Castello

发明人： Luciano Tomasini ,  Rinaldo Castello

IPC分类号： H03H7/06 ,  H03H7/00 ,  H03H11/34 ,  H03H11/36 ,  H04M1/60 ,  H04M1/76 ,  H03H11/04

CPC分类号： H03H7/004 ,  H04M1/6025

摘要： A monolithically integrated AC coupling circuit is presented for DC uncoupling and AC coupling (typically in telephone applications) to an input signal. The AC coupler includes a high-pass filter having a first pole at a frequency well below a frequency of interest and a zero at zero frequency. The AC coupler also includes a pole/zero doublet between the frequency of the first pole and the frequency of interest. The frequency of the first pole for a specified error is increased by addition of the doublet. Because the frequency of the first pole is increased, the size of the required capacitors is decreased, enabling integration. An implementation of the circuit using switched capacitor techniques is described. An alternative circuit employing a unit gain interface is presented. The alternative circuit reduces the dynamic range and driving voltage requirements of its field-effect transistors.

摘要翻译： 提出了一种单片集成AC耦合电路，用于DC分离和AC耦合（通常在电话应用中）到输入信号。 AC耦合器包括高通滤波器，其具有在低于感兴趣频率的频率处的第一极点和零频率处的零点。 AC耦合器还包括在第一极的频率和感兴趣的频率之间的极点/零点。 通过添加双峰来增加指定误差的第一极的频率。 由于第一极的频率增加，所需电容的尺寸减小，从而实现集成。 描述使用开关电容器技术的电路的实现。 提出了采用单位增益接口的替代电路。 替代电路降低了其场效应晶体管的动态范围和驱动电压要求。

公开(公告)号：US5598467A

公开(公告)日：1997-01-28

申请号：US353095

申请日：1994-12-09

申请人： Duncan J. Bremner ,  Roger K. Benton ,  James B. Wieser

发明人： Duncan J. Bremner ,  Roger K. Benton ,  James B. Wieser

IPC分类号： H04M1/58 ,  H04M1/76

CPC分类号： H04M1/585 ,  H04M1/76

摘要： A signal interface circuit with selectable signal interface parameters for a telephone subscriber line includes an impedance circuit having a selectable impedance value, signal terminals having an associated, definable termination impedance, a transmitter circuit having a definable transmitter transfer function and a receiver circuit having a definable receiver transfer function. The signal terminals connect to an external signal line pair having an associated line impedance for conducting outgoing and incoming signals therefrom and thereto, respectively. The transmitter circuit receives the outgoing signal from the signal terminals and provides a transmit signal in accordance with its transmitter transfer function. The receiver circuit, which includes a differential transconductance amplifier, receives an input signal and the transmit signal and provides the incoming signal to the signal terminals in accordance with its receiver transfer function. The termination impedance, transmitter transfer function and receiver transfer function are all defined by the selectable impedance, with the termination impedance defined to match the line impedance.

摘要翻译： 具有用于电话用户线路的可选信号接口参数的信号接口电路包括具有可选阻抗值的阻抗电路，具有相关联的可定义终端阻抗的信号端子，具有可定义的发射机传输功能的发射机电路和具有可定义的可定义的接收机电路 接收机传递功能。 信号端子连接到具有相关联的线路阻抗的外部信号线对，分别用于传送和输入信号。 发射机电路接收来自信号终端的输出信号，并根据发射机传输功能提供发射信号。 包括差分跨导放大器的接收器电路接收输入信号和发送信号，并根据其接收器传递函数向信号端子提供输入信号。 终端阻抗，发射机传输功能和接收机传输功能都由可选阻抗定义，终端阻抗定义为匹配线路阻抗。

公开(公告)号：US5515434A

公开(公告)日：1996-05-07

申请号：US267434

申请日：1994-06-29

申请人： Gerald M. Cotreau

发明人： Gerald M. Cotreau

IPC分类号： H04M19/02 ,  H04M1/76

CPC分类号： H04M19/026

摘要： A current mode subscriber line interface circuit (SLIC) for telephone system in which AC and De impedances for tip and ring connections of the SLIC are separately set. A DC filter separates the DC and AC components of tip and ring currents, and a current amplifier amplifies the AC components separately from the DC components. A pair of resistors set the AC impedance value, and also may be used to set SLIC four-wire to two-wire gain separately from SLIC two-wire to four-wire gain.

摘要翻译： 用于电话系统的电流模式用户线接口电路（SLIC），其中分别设置用于SLIC的尖端和环形连接的AC和De阻抗。 DC滤波器分离尖端和环形电流的直流和交流分量，电流放大器与直流分量分开放大AC组件。 一对电阻设置交流阻抗值，也可用于将SLIC四线到两线制增益与SLIC二线到四线增益分开设置。

公开(公告)号：US5515433A

公开(公告)日：1996-05-07

申请号：US298146

申请日：1994-08-30

申请人： William I. H. Chen

发明人： William I. H. Chen

IPC分类号： H04M19/00 ,  H04M1/76

CPC分类号： H04M19/001

摘要： A line feed circuit employing a low-inductance transformer, and providing a major portion of the terminating impedance as line feed resistors connected between a telephone line and the transformer primary. A low impedance output amplifier drives a low resistance transformer secondary, thus reducing the need for large transformer inductances. By connecting the line feed resistors between the transformer and the telephone line, high voltage surges are absorbed by the resistors, and thus little is dissipated in the transformer. The transformer can be made physically small, because of the reduced inductance, reduced winding insulation, and reduced power requirements. The resistance forward type of line feed circuit lends itself well to simple implementation with flux cancellation and impedance synthesis circuits.

摘要翻译： 采用低电感变压器的线路馈电电路，并且将终端阻抗的主要部分提供为连接在电话线路和变压器初级线路之间的线路馈电电阻器。 低阻抗输出放大器驱动低电阻变压器次级，从而减少对大型变压器电感的需求。 通过连接变压器和电话线之间的馈线电阻，高压浪涌被电阻吸收，因此在变压器中几乎没有消散。 由于电感减小，绕组绝缘减少，功率要求降低，变压器可以做到物理上小。 线路馈电电路的电阻前馈类型很好地实现了具有磁通消除和阻抗合成电路的简单实现。

公开(公告)号：US5329585A

公开(公告)日：1994-07-12

申请号：US983197

申请日：1992-11-30

申请人： David M. Susak ,  Tony Takeshian ,  Dennis L. Welty

发明人： David M. Susak ,  Tony Takeshian ,  Dennis L. Welty

IPC分类号： H04M19/00 ,  H04M1/76 ,  H04M7/04

CPC分类号： H04M19/005

摘要： A subscriber line interface circuit (SLIC) sets AC and DC output impedances as seen by first and second transmission signals. The common mode variation and differential variation of the first and second transmission signals is AC-sensed to provide a common mode feedback signal and a differential feedback signal which in turn controls the AC output impedance. The DC component of the first and second transmission signals is blocked allowing downstream amplifiers to operate at reduced power supply potentials. The DC variation of the first and second transmission signals is also sensed for providing a DC feedback signal to control the DC output impedance.

摘要翻译： 用户线接口电路（SLIC）设置由第一和第二传输信号所见的AC和DC输出阻抗。 对第一和​​第二传输信号的共模变化和差分变化进行AC感测，以提供共模反馈信号和差分反馈信号，该反馈信号又控制AC输出阻抗。 第一和第二传输信号的DC分量被阻塞，允许下游放大器以降低的电源电位工作。 还检测第一和第二传输信号的DC变化，以提供DC反馈信号来控制DC输出阻抗。

公开(公告)号：US4996710A

公开(公告)日：1991-02-26

申请号：US411378

申请日：1989-09-25

申请人： Toshiaki Takahashi ,  Yasuji Sato

发明人： Toshiaki Takahashi ,  Yasuji Sato

IPC分类号： H04M1/58 ,  H04M1/76 ,  H04Q3/58

CPC分类号： H04M1/76 ,  H04M1/58

摘要： The present invention disclose a switching system including an exchange coupled to a plurality of central office lines and PBX's telephone lines, and a plurality of telephone sets. Each telephone set includes a side-tone adjusting circuit which adjusts a side-tone in response to a balanced impedance to obtain a suitable side-tone. When the exchange receives a speaking path selection request, representing one of the lines, from the telephone set, it determines one of a plurality of predetermined impedance information and makes a speaking path between the selected line and the telephone set. The telephone set selects one of the balanced impedances in response to the determined impedance information.

摘要翻译： 本发明公开了一种交换系统，包括耦合到多个中心局线路和PBX电话线路的交换机以及多个电话机。 每个电话机包括侧音调节电路，其响应于平衡阻抗来调节侧音以获得合适的侧音。 当交换机从电话机接收到表示其中一行的说话路径选择请求时，它确定多个预定阻抗信息中的一个并且在所选择的线路和电话机之间形成通话路径。 电话机根据所确定的阻抗信息选择平衡阻抗之一。

公开(公告)号：US4894863A

公开(公告)日：1990-01-16

申请号：US103385

申请日：1987-09-30

申请人： Emil Navratil ,  Armin Doll

发明人： Emil Navratil ,  Armin Doll

IPC分类号： H04M1/60 ,  H04M1/76

CPC分类号： H04M1/76 ,  H04M1/6008

摘要： A method for gain control of telephone sets having an electronic speech circuit and an apparatus for carrying out the method include a modulation current source. Two line terminals connect the modulation current source to a telephone line. A microphone amplifier has an input connected to a microphone terminal and an output controlling the modulation current source for generating a line signal. Signals are derived from the modulation current source and converted into mutually associated measurement signals and threshold value signals. The mutually associated measurement and threshold value signals are compared with one another. The gain of the microphone amplifier is regulated as a function of the result of the comparison.

摘要翻译： 一种具有电子语音电路的电话机的增益控制方法以及用于执行该方法的装置包括调制电流源。 两条线路端子将调制电流源连接到电话线。 麦克风放大器具有连接到麦克风端子的输入端和控制调制电流源的输出端，用于产生线路信号。 信号从调制电流源导出，并转换成相互关联的测量信号和阈值信号。 相互关联的测量和阈值信号彼此进行比较。 麦克风放大器的增益作为比较结果的函数进行调节。

公开(公告)号：US4796295A

公开(公告)日：1989-01-03

申请号：US911833

申请日：1986-09-26

申请人： Michael J. Gay ,  Johannes A. Gutmann

发明人： Michael J. Gay ,  Johannes A. Gutmann

IPC分类号： H04M1/76 ,  H04M1/58

CPC分类号： H04M1/585

摘要： A circuit is disclosed for use in telephone handsets having a line signal node (1), a microphone signal input (20) and an output to an earphone amplifier. There is provided two voltage feedback loops via respective impedance networks (10, 11) and a current feedback loop (5, 7, 14). These feedback loops determine the impedance presented to the line at the signal node with specific voltage/current characteristics and signal frequencies. The first voltage feedback loop in conjunction with the current feedback loop defines the signal frequency impedance and the second voltage feedback loop defines the DC mask presented to the line.

摘要翻译： 公开了一种用于具有线路信号节点（1），麦克风信号输入（20）和到耳机放大器的输出的电话手机中的电路。 通过相应的阻抗网络（10,11）和电流反馈回路（5,7,14）提供两个电压反馈回路。 这些反馈环路确定了具有特定电压/电流特性和信号频率的信号节点处线路的阻抗。 与电流反馈回路相结合的第一个电压反馈回路定义了信号频率阻抗，第二个电压反馈回路定义了呈现给该线路的直流屏蔽。

公开(公告)号：US4742540A

公开(公告)日：1988-05-03

申请号：US931410

申请日：1986-11-14

申请人： Pierre J. Schingh

发明人： Pierre J. Schingh

IPC分类号： H03K17/00 ,  H04B1/58 ,  H04M1/76

CPC分类号： H04B1/586 ,  H04M1/76

摘要： A circuit for switching one of two impedance networks to a line carrying AC signals comprising a unity gain amplifier having differential inputs connected across the first one of the impedance networks, and one of the differential inputs and an output connected across the second one of the impedance networks, and a microprocessor control terminal connected to the other of the differential inputs for applying one of either a high impedance or AC ground thereto. The circuit is small, inexpensive, requires no electromechanical parts, and takes up very little circuit board area.

摘要翻译： 一种用于将两个阻抗网络中的一个切换到承载AC信号的线路的电路，所述线路包括具有连接在所述阻抗网络中的所述第一阻抗网络上的差分输入的单位增益放大器，以及所述差分输入端和所述阻抗中的所述第二阻抗 网络和连接到另一个差分输入端的微处理器控制端子，用于将高阻抗或AC接地中的一个施加到其上。 电路小巧，价格低廉，不需要机电零件，电路板面积很小。

公开(公告)号：US4661978A

公开(公告)日：1987-04-28

申请号：US686254

申请日：1984-12-26

申请人： Hideyuki Hirata

发明人： Hideyuki Hirata

IPC分类号： H03H11/40 ,  H03F1/48 ,  H03H11/46 ,  H04M19/00 ,  H04Q3/42 ,  H04M1/76

CPC分类号： H03F1/48 ,  A61J1/1425 ,  H04M19/005

摘要： A subscriber line interface circuit described wherein a pair of line terminals are connected to a subscriber loop and a pair of output terminals are connected to a telecommunication exchange. A first amplifier is provided having a first pair of input terminals coupled to the line terminals and a second pair of input terminals. The first amplifier has a unity gain over a path from the input terminals of the first pair to said output terminals and a gain K over a path from the terminals of the second pair to said output terminals. A pair of reference resistors are cross-coupled from said output terminals to the line terminals, each of the reference resistors having a resistance Ro. A second amplifier is connected from the line terminals to the terminals of the second pair, the second amplifier having a transfer function -Ro/K.multidot.Zt, where Zt is an impedance to be synthesized across the line terminals.

摘要翻译： 一种用户线接口电路，其中一对线路终端连接到用户环路，一对输出终端连接到电信交换机。 提供了第一放大器，其具有耦合到线路端子的第一对输入端子和第二对输入端子。 第一放大器在从第一对的输入端子到所述输出端子的路径上具有单位增益，并且在从第二对端子到所述输出端子的路径上具有增益K. 一对参考电阻器从所述输出端子交叉耦合到线路端子，每个参考电阻器具有电阻Ro。 第二放大器从线路端子连接到第二对的端子，第二放大器具有传递函数-Ro / KxZt，其中Zt是要在线路端子上合成的阻抗。