公开(公告)号：WO1998008336A1

公开(公告)日：1998-02-26

申请号：PCT/US1997014479

申请日：1997-08-18

Applicant: ADVANCED MICRO DEVICES, INC.

Inventor： ADVANCED MICRO DEVICES, INC. ,  ZHOU, Yan ,  SCHOPFER, Walter, S.

IPC: H04M19/00

CPC classification number: H04M19/005

Abstract: A communication system includes a SLIC device and a SLAC device. The SLIC device and the SLAC device cooperate to control the power level provided to a subscriber line. The SLAC device includes a digital control circuit which receives a parameter signal indicative of a first parameter of the electrical power. The digital control circuit provides a digital control signal to the SLIC device in response to a sample digital control signal and the digital parameter signal. Preferably, the digital parameter signal relates to a sensed current signal and the sample digital control signal relates to a desired voltage signal. The digital control circuit can be implemented hardware or software.

Abstract translation: 通信系统包括SLIC设备和SLAC设备。 SLIC设备和SLAC设备协作来控制提供给用户线的功率电平。 SLAC设备包括数字控制电路，其接收指示电功率的第一参数的参数信号。 数字控制电路响应于采样数字控制信号和数字参数信号向SLIC设备提供数字控制信号。 优选地，数字参数信号涉及感测的电流信号，并且采样数字控制信号涉及期望的电压信号。 数字控制电路可以实现硬件或软件。

公开(公告)号：WO1996027970A1

公开(公告)日：1996-09-12

申请号：PCT/US1996002835

申请日：1996-03-01

Applicant: ADVANCED MICRO DEVICES, INC.

Inventor： ADVANCED MICRO DEVICES, INC. ,  ZHOU, Yan

IPC: H04M03/00

CPC classification number: H04M19/005 ,  H04M3/005

Abstract: DC level control for an electronic telephone line card which filters the DC component from the input audio signal, determines the gain setting of the transmit path, develops a DC adjust voltage opposite to that of the DC shift component and subtracts the DC adjust voltage to the input voltage to cancel the DC shift component. A quantized, discontinuous feedback path is implemented to respond only to DC shifts so the AC operation remains substantially unaffected. Such discontinuous feedback eliminates stability and impedance matching problems introduced with continuous feedback solutions. A DC control circuit according to the present invention includes a low pass filter for detecting DC shifts, a quantizer for asserting an incremental signal, a threshold detector for activating adjustment functions, and an accumulator for developing the DC adjust voltage by incremental steps. A long term low pass filter and reset circuit resets the accumulator to cancel residual DC adjust voltages which might otherwise reduce the dynamic range of the telephone line transmit path.

Abstract translation: 对来自输入音频信号对DC分量进行滤波的电子电话线卡的DC电平控制，确定发送路径的增益设定，产生与DC移位分量相反的DC调整电压，并将DC调整电压减去为 输入电压来取消直流偏移分量。 实现量化的不连续反馈路径以仅响应于DC偏移，使得AC操作基本上不受影响。 这种不连续的反馈消除了连续反馈解决方案引入的稳定性和阻抗匹配问题。 根据本发明的直流控制电路包括用于检测直流偏移的低通滤波器，用于断言增量信号的量化器，用于启动调节功能的阈值检测器，以及用于通过增量步长产生直流调节电压的累加器。 长期的低通滤波器和复位电路使累加器复位以消除残留的DC调整电压，否则可能会降低电话线路传输路径的动态范围。

公开(公告)号：EP0792548A1

公开(公告)日：1997-09-03

申请号：EP96908607.0

申请日：1996-03-01

Applicant: Advanced Micro Devices, Inc.

Inventor： ZHOU, Yan

IPC: H04M3 ,  H04M19

CPC classification number: H04M19/005 ,  H04M3/005

Abstract: DC level control for an electronic telephone line card which filters the DC component from the input audio signal, determines the gain setting of the transmit path, develops a DC adjust voltage opposite to that of the DC shift component and subtracts the DC adjust voltage to the input voltage to cancel the DC shift component. A quantized, discontinuous feedback path is implemented to respond only to DC shifts so the AC operation remains substantially unaffected. Such discontinuous feedback eliminates stability and impedance matching problems introduced with continuous feedback solutions. A DC control circuit according to the present invention includes a low pass filter for detecting DC shifts, a quantizer for asserting an incremental signal, a threshold detector for activating adjustment functions, and an accumulator for developing the DC adjust voltage by incremental steps. A long term low pass filter and reset circuit resets the accumulator to cancel residual DC adjust voltages which might otherwise reduce the dynamic range of the telephone line transmit path.

Abstract translation: 对来自输入音频信号的DC分量进行滤波的电子电话线卡的DC电平控制，确定发送路径的增益设置，产生与DC移位分量相反的DC调整电压，并将DC调整电压减去 输入电压来抵消直流偏移分量。 量化的不连续的反馈路径被实现为仅响应DC偏移，因此AC操作基本不受影响。 这种不连续的反馈消除了连续反馈解决方案引入的稳定性和阻抗匹配问题。 根据本发明的DC控制电路包括用于检测DC偏移的低通滤波器，用于确定增量信号的量化器，用于激活调节功能的阈值检测器以及用于通过增量步骤产生DC调节电压的累加器。 长期低通滤波器和复位电路复位累加器以消除残留的DC调整电压，否则可能会降低电话线发送路径的动态范围。

公开(公告)号：EP0929968A1

公开(公告)日：1999-07-21

申请号：EP97937302.0

申请日：1997-08-18

Applicant: Advanced Micro Devices, Inc.

Inventor： ZHOU, Yan ,  SCHOPFER, Walter, S.

IPC: H04M19

CPC classification number: H04M19/005

Abstract: A communication system includes a SLIC device and a SLAC device. The SLIC device and the SLAC device cooperate to control the power level provided to a subscriber line. The SLAC device includes a digital control circuit which receives a parameter signal indicative of a first parameter of the electrical power. The digital control circuit provides a digital control signal to the SLIC device in response to a sample digital control signal and the digital parameter signal. Preferably, the digital parameter signal relates to a sensed current signal and the sample digital control signal relates to a desired voltage signal. The digital control circuit can be implemented hardware or software.