Current supply circuit
    1.
    发明授权
    Current supply circuit 失效
    电流供应电路

    公开(公告)号:US4465967A

    公开(公告)日:1984-08-14

    申请号:US342791

    申请日:1982-01-26

    IPC分类号: H04M19/00 G05F1/46

    CPC分类号: H04M19/008

    摘要: A current supply circuit comprises a DC power feed circuit exhibiting a constant current characteristic for a power source and a constant resistance characteristic for a load, a first detecting circuit for detecting a load current or a load voltage, a DC-DC converter circuit inserted between the power source and the DC power feed circuit, a second detecting circuit for detecting an output voltage from the DC-DC converter circuit; and an operation circuit coupled at the input with the output of the first detecting circuit and the output of the second detecting circuit for controlling the DC-DC converter circuit by the output thereof. The DC-DC converter circuit is so controlled as to produce a voltage representative of the sum of a voltage drop across the load and a fixed voltage necessary for the operation of the DC power feed circuit.

    摘要翻译: 电流源电路包括对电源呈现恒定电流特性的直流供电电路和用于负载的恒定电阻特性,用于检测负载电流或负载电压的第一检测电路,插入在电源之间的DC-DC转换器电路 电源和直流供电电路,用于检测来自DC-DC转换器电路的输出电压的第二检测电路; 以及在输入端耦合第一检测电路的输出和第二检测电路的输出的操作电路,用于通过其输出控制DC-DC转换器电路。 DC-DC转换器电路被控制以产生代表负载两端的电压降和DC供电电路的操作所需的固定电压之和的电压。

    Loop detecting circuit
    2.
    发明授权
    Loop detecting circuit 失效
    环路检测电路

    公开(公告)号:US4360709A

    公开(公告)日:1982-11-23

    申请号:US184182

    申请日:1980-09-04

    IPC分类号: H04Q3/72 H04M3/22 H04B3/46

    CPC分类号: H04M3/2272

    摘要: A circuit for detecting a closed loop formed by actuation of a telephone set, the loop being indicative of a connection between the telephone set and an exchange through a ring line and a tip line. The detecting circuit comprises generators for generating first and second detection signals having amplitudes proportional to a ring line current and a tip line current respectively, a summing circuit for summing the detection signals and a comparator for comparing the outputs of the summing circuit and a reference value and delivering an output depending upon the result of comparison.

    摘要翻译: 一种用于检测通过致动电话机而形成的闭环的电路,所述回路指示通过环线和尖端线路在电话机和交换机之间的连接。 检测电路包括用于产生具有与环形线电流和尖端线电流成比例的振幅的第一和第二检测信号的发生器,用于对检测信号求和的加法电路和用于比较加法电路的输出和参考值的比较器 并根据比较结果输出输出。

    Hybrid circuit in a telephone subscriber interface circuit
    3.
    发明授权
    Hybrid circuit in a telephone subscriber interface circuit 失效
    电话用户接口电路中的混合电路

    公开(公告)号:US4491700A

    公开(公告)日:1985-01-01

    申请号:US325056

    申请日:1981-11-25

    CPC分类号: H04M19/005 H04B1/586

    摘要: A hybrid circuit composed of semiconductor current amplifiers without an inductance and large capacitance has been found. The DC speech current supplied by the DC power source (33) and the speech signal from the modem (28) are adjusted by the current amplifiers (17a, 17b) so that the subscriber line (2) is terminated with the predetermined impedance (600 ohms), and the speech signal from the subscriber line (2) is transferred to the modem (28) through the AC monitor circuits (24a, 24b). The common mode noise induced on the subscriber line (2) is cancelled by adjusting the input current of said current amplifiers (17a, 17b) by the common mode noise detector (22) and the common mode noise monitor circuits (23a, 23b). The speech signal from the modem (28) to the subscriber line (2) does not return to the modem (28) because of the cancellation operation by the return signal detector circuit (32). The present hybrid circuit is suitable to compose a semiconductor integrated circuit (IC) because no inductance is used and no large capacitor is used.

    摘要翻译: 已经发现由没有电感和大电容的半导体电流放大器组成的混合电路。 由直流电源(33)提供的DC语音电流和来自调制解调器(28)的语音信号由电流放大器(17a,17b)进行调整,使得用户线(2)以预定阻抗(600 欧姆),并且来自用户线(2)的语音信号通过AC监控电路(24a,24b)传送到调制解调器(28)。 通过共模噪声检测器(22)和共模噪声监视电路(23a,23b)调节所述电流放大器(17a,17b)的输入电流来消除在用户线(2)上感应的共模噪声。 由于返回信号检测器电路(32)的取消操作,来自调制解调器(28)到用户线路(2)的语音信号不返回到调制解调器(28)。 本混合电路适用于组成半导体集成电路(IC),因为不使用电感,不使用大电容器。

    Time division telephone switching systems
    4.
    发明授权
    Time division telephone switching systems 失效
    时分电话交换系统

    公开(公告)号:US4254498A

    公开(公告)日:1981-03-03

    申请号:US002208

    申请日:1979-01-09

    IPC分类号: H04Q11/04

    CPC分类号: H04Q11/04

    摘要: The telephone switching system comprises a plurality of speech path units, a juncture switch unit for interconnecting the speech path units, a central processing unit for controlling the speech path units and the junctor switch unit. Each speech path unit comprises a time switch which shifts a signal which is time-division-multiplexed from time slots of a plurality of incoming highways to other time slots on a plurality of outgoing highways, a digital trunk circuit for processing a register signal received by the time slot and other control signals, and a speech path control equipment which receives and distributes a control signal between the time division switch, the digital trunk circuit and the central processing unit. The junctor switch unit is constructed to change the connections between the speech path units by using a plurality of time slots as one group, whereby the change of connection between respective speech path units by the junctor switch and effects changes in terms of a group units of a plurality of time slots when the number of the speech path units is varied.

    摘要翻译: 电话交换系统包括多个语音路径单元,用于互连语音路径单元的接合开关单元,用于控制语音路径单元的中央处理单元和连接器开关单元。 每个语音路径单元包括一个时间开关,该时间开关将多个输入高速公路的时隙的时分多路复用的信号移位到多条输出高速公路上的其他时隙,用于处理由 时隙和其他控制信号,以及语音路径控制设备,其在时分开关,数字中继电路和中央处理单元之间接收和分配控制信号。 通过使用多个时隙作为一组,构成了通过使用多个时隙来改变语音路径单元之间的连接的顺序切换单元,由此,通过连接器切换的各个语音路径单元之间的连接的改变和效果根据 当语音路径单元的数量变化时,多个时隙。