公开(公告)号：US07305039B2

公开(公告)日：2007-12-04

申请号：US11204627

申请日：2005-08-16

Applicant: Kevin T. Chan

Inventor： Kevin T. Chan

IPC: H04B3/00 ,  H03M1/66

CPC classification number: H04L25/08 ,  H04B3/23 ,  H04B3/32 ,  H04L12/10 ,  H04L25/0276 ,  H04L25/0282 ,  H04L25/0286 ,  H04L25/03834 ,  H04L25/14

Abstract: A power efficient and reduced electromagnetic interference (EMI) emissions transmitter for unshielded twisted pair (UTP) data communication applications. Transmit data is processed by a digital filter. The digital filter output data is converted to a current-mode analog waveform by a digital-to-analog converter (DAC). The digital filter is integrated with the DAC binaiy decoder in a memory device such as a ROM with time multiplexed output. DAC line driver cells are adaptively configurable to operate in either a class-A or class-B mode depending on the desired operational modality. A discrete-time analog filter is integrated with the DAC line driver to provide additional EMI emissions suppression. An adaptive electronic transmission signal cancellation circuit separates transmit data from receive data in a bidirectional communication system operating in full duplex mode. For a multi-transmitter system, timing circuitry staggers the time base of each transmitter to reduce the aggregate EMI emissions of the multi-transmitter system.

Abstract translation: 用于非屏蔽双绞线（UTP）数据通信应用的功率高效和降低的电磁干扰（EMI）发射器。 发送数据由数字滤波器处理。 数字滤波器输出数据通过数/模转换器（DAC）转换为电流模式模拟波形。 数字滤波器与诸如具有时间复用输出的ROM的存储器件中的DAC比特解码器集成。 DAC线路驱动器单元可自适应地配置为根据所需的操作模式在A类或B类模式下工作。 离散时间模拟滤波器与DAC线路驱动器集成，以提供额外的EMI发射抑制。 自适应电子传输信号消除电路在全双工模式下工作的双向通信系统中分离发送数据与接收数据。 对于多发射机系统，定时电路交错了每个发射机的时基，以减少多发射机系统的总EMI辐射。

公开(公告)号：US06963616B2

公开(公告)日：2005-11-08

申请号：US10717127

申请日：2003-11-19

Applicant: Kevin T. Chan

Inventor： Kevin T. Chan

IPC: H04B1/38 ,  H04B3/00 ,  H04B3/23 ,  H04B15/00 ,  H04J11/00 ,  H04L5/16 ,  H04L12/10 ,  H04L25/00 ,  H04L25/02 ,  H04L25/03 ,  H04L25/08 ,  H04L25/14 ,  H04L25/49 ,  H04L27/00 ,  H04L27/04

CPC classification number: H04L25/08 ,  H04B3/23 ,  H04B3/32 ,  H04L12/10 ,  H04L25/0276 ,  H04L25/0282 ,  H04L25/0286 ,  H04L25/03834 ,  H04L25/14

Abstract: A power efficient and reduced electromagnetic interference (EMI) emissions transmitter for unshielded twisted pair (UTP) data communication applications. Transmit data is processed by a digital filter. The digital filter output data is converted to a current-mode analog waveform by a digital-to-analog converter (DAC). The digital filter is integrated with the DAC binary decoder in a memory device such as a ROM with time multiplexed output. DAC line driver cells are adaptively configurable to operate in either a class-A or class-B mode depending on the desired operational modality. A discrete-time analog filter is integrated with the DAC line driver to provide additional EMI emissions suppression. An adaptive electronic transmission signal cancellation circuit separates transmit data from receive data in a bidirectional communication system operating in full duplex mode. For a multi-transmitter system, timing circuitry staggers the time base of each transmitter to reduce the aggregate EMI emissions of the multi-transmitter system.

Abstract translation: 用于非屏蔽双绞线（UTP）数据通信应用的功率高效和降低的电磁干扰（EMI）发射器。 发送数据由数字滤波器处理。 数字滤波器输出数据通过数/模转换器（DAC）转换为电流模式模拟波形。 数字滤波器与DAC二进制解码器集成在诸如具有时间复用输出的ROM的存储器件中。 DAC线路驱动器单元可自适应地配置为根据所需的操作模式在A类或B类模式下工作。 离散时间模拟滤波器与DAC线路驱动器集成，以提供额外的EMI发射抑制。 自适应电子传输信号消除电路在全双工模式下工作的双向通信系统中分离发送数据与接收数据。 对于多发射机系统，定时电路交错了每个发射机的时基，以减少多发射机系统的总体EMI发射。

公开(公告)号：US06888405B2

公开(公告)日：2005-05-03

申请号：US10372778

申请日：2003-02-26

Applicant: Felix Cheung ,  Kevin T. Chan ,  Siavash Fallahi

Inventor： Felix Cheung ,  Kevin T. Chan ,  Siavash Fallahi

IPC: H03G1/00 ,  H03F1/36

CPC classification number: H03G1/0088

Abstract: A programable gain amplifier (PGA) has an amplifier and a variable resistor that is connected to the output of the amplifier. The variable resistor includes a resistor that is connected to a reference voltage and multiple parallel taps that tap off the resistor. A two-stage switch network having fine stage switches and coarse stage switches connects the resistor taps to an output node of the PGA. The taps and corresponding fine stage switches are arranged into two or more groups, where each group has n-number of fine stage switches and corresponding taps. One terminal of each fine stage switch is connected to the corresponding resistor tap, and the other terminal is connected to an output terminal for the corresponding group. The coarse stage switches select from among the groups of fine stage switches, and connect to the output of the PGA. During operation, one selected tap is connected to the output of the PGA by closing the appropriate fine stage switch and coarse stage switch, where the selected tap defines a selected group of the fine stage switches. Additionally, one fine stage switch is closed in each of the non-selected groups of fine stage switches. In one embodiment, the location of the closed switches in the non-selected groups is the mirror image of the location in an adjacent group. This reduces the transient voltages that occur when tap selection changes from one group to another.

公开(公告)号：US06833734B2

公开(公告)日：2004-12-21

申请号：US10695746

申请日：2003-10-30

Applicant: Kevin T. Chan

Inventor： Kevin T. Chan

IPC: H03K190175

CPC classification number: H04L25/0266 ,  Y10T307/305

Abstract: A line driver selectively drives one of two transmission lines. The line driver includes a differential amplifier connected to first and second differential switches. The first differential switch is connected between an output of the differential amplifier and a first of two transmission lines. The second differential switch is connected to the output of the differential amplifier and to the second of two transmission lines. The first and second differential switches are controlled by respective first and second control signals. The output of the differential amplifier is connected to either the first or the second transmission line in response to the first and second control signals. The differential switches include loopback protection to an prevent an incoming signal from passing from one transmission line to another during power down mode.

Abstract translation: 线路驱动器选择性地驱动两条传输线之一。 线路驱动器包括连接到第一和第二差分开关的差分放大器。 第一差分开关连接在差分放大器的输出和两条传输线中的第一条之间。 第二差分开关连接到差分放大器的输出端和两条传输线路中的第二个。 第一和第二差分开关由相应的第一和第二控制信号控制。 差分放大器的输出响应于第一和第二控制信号连接到第一或第二传输线。 差分开关包括环回保护，以防止输入信号在掉电模式期间从一条传输线路传递到另一条传输线路。

公开(公告)号：US06411647B1

公开(公告)日：2002-06-25

申请号：US09429887

申请日：1999-10-29

Applicant: Kevin T. Chan

Inventor： Kevin T. Chan

IPC: H04L2700

CPC classification number: H04L25/08 ,  H04B3/23 ,  H04B3/32 ,  H04L12/10 ,  H04L25/0276 ,  H04L25/0282 ,  H04L25/0286 ,  H04L25/03834 ,  H04L25/14

Abstract: A power efficient and reduced electromagnetic interference (EMI) emissions transmitter for unshielded twisted pair (UTP) data communication applications. Transmit data is interpolated by N and processed by a digital filter to obtain the pulse shape required by the particular communication application. The digital filter output data is converted to a current-mode analog waveform by a digital-to-analog converter (DAC). The digital filter is integrated with the DAC binary decoder in a memory device such as a ROM with time multiplexed output. When implemented in such manner, the logical implementation and memory replaces digital filtering circuits, DAC decoding logic circuit and re-synchronization logic circuits that are conventionally implemented in hardware. Thus, the hardware functionality of these circuits is rendered into arithmetic form and implemented in a memory device.

Abstract translation: 用于非屏蔽双绞线（UTP）数据通信应用的功率高效和降低的电磁干扰（EMI）发射器。 发送数据由N内插并由数字滤波器处理以获得特定通信应用所需的脉冲形状。 数字滤波器输出数据通过数/模转换器（DAC）转换为电流模式模拟波形。 数字滤波器与DAC二进制解码器集成在诸如具有时间复用输出的ROM的存储器件中。 当以这种方式实现时，逻辑实现和存储器替代了常规地以硬件实现的数字滤波电路，DAC解码逻辑电路和重新同步逻辑电路。 因此，这些电路的硬件功能被呈现为算术形式并在存储器件中实现。

公开(公告)号：US06389077B1

公开(公告)日：2002-05-14

申请号：US09568520

申请日：2000-05-09

Applicant: Kevin T. Chan

Inventor： Kevin T. Chan

IPC: H04B300

CPC classification number: H04L25/08 ,  H04B3/23 ,  H04B3/32 ,  H04L12/10 ,  H04L25/0276 ,  H04L25/0282 ,  H04L25/0286 ,  H04L25/03834 ,  H04L25/14

Abstract: A power efficient and reduced electromagnetic interference (EMI) emissions transmitter for unshielded twisted pair (UTP) data communication applications. Transmit data is processed by a digital filter. The digital filter output data is converted to a current-mode analog waveform by a digital-to-analog converter (DAC). The digital filter is integrated with the DAC binary decoder in a memory device such as a ROM with time multiplexed output. DAC line driver cells are adaptively configurable to operate in either a class-A or a class-B mode depending on the desired operational modality. A discrete-time analog filter is integrated with the DAC line driver to provide additional EMI emissions suppression. An adaptive electronic transmission signal cancellation circuit separates transmit data from receive data in a bidirectional communication system operating in full duplex mode. For a multi-transmitter system, timing circuitry staggers the time base of each transmitter to reduce the aggregate EMI emissions of the multi-transmitter system.

公开(公告)号：US06185263B2

公开(公告)日：2001-02-06

申请号：US09399202

申请日：1999-09-17

Applicant: Kevin T. Chan

Inventor： Kevin T. Chan

IPC: H04L2704

CPC classification number: H04B3/02

Abstract: A power efficient and reduced electromagentic interference (EMI) emissions transmitter for unshielded twisted pair (UTP) data communication applications. Digital transmit data is converted to a current-mode differential signal analog waveform by a digital-to-analog converter (DAC). DAC line driver cells are adaptively configurable to operate in either a class-A or a class-B mode depending on the desired operational modality. Selection logic circuitry asserts command signals to individual line driver cells which operate the cells in either class-A or class-B, in operative response to a DAC control word. The same DAC control word adaptively configures the line driver cells to operate in accordance with at least two ethernet-type transmission standards. Numbers of line driver cells are adaptively disabled in operative response to a DAC control word, to conform the transmitter to differing transmission standards with differing voltage swing requirements.

Abstract translation: 用于非屏蔽双绞线（UTP）数据通信应用的功率高效和降低的电磁干扰（EMI）发射器。 数字发送数据由数模转换器（DAC）转换为电流模式差分信号模拟波形。 DAC线路驱动器单元可以自适应地配置，以根据所需的操作模式在A类或B类模式下工作。 选择逻辑电路将对A类或B类中的单元进行操作的各个线路驱动器单元的命令信号置于对DAC控制字的操作响应中。 相同的DAC控制字自适应地配置线路驱动器单元根据至少两个以太网型传输标准进行操作。 线路驱动器单元的数量在对DAC控制字的操作响应中被自适应地禁用，以使发射机符合具有不同电压摆动要求的不同传输标准。

公开(公告)号：US5404405A

公开(公告)日：1995-04-04

申请号：US105323

申请日：1993-08-05

Applicant: Kevin T. Collier ,  Kevin T. Chan

Inventor： Kevin T. Collier ,  Kevin T. Chan

IPC: H04B1/16 ,  H04H5/00

CPC classification number: H04B1/1653

Abstract: A digital FM stereo decoder uses the phase characteristics of linear phase FIR filters, together with a trignometric operation, to generate a 38 kHz subcarrier signal from a 19 kHz pilot. The subcarrier signal is mixed with the input composite signal from which the pilot has been removed to shift its L-R component to baseband; the linear phase FIR filters also maintain phase coherence between the subcarrier and the composite signals. A low distortion output is obtained without the use of a phase locked loop for the regeneration of the subcarrier signal.

Abstract translation: 数字FM立体声解码器使用线性相位FIR滤波器的相位特性以及轨道运算来产生来自19kHz导频的38kHz子载波信号。 子载波信号与导频已经被去除的输入复合信号混合，以将其L-R分量移位到基带; 线性相位FIR滤波器也保持副载波和复合信号之间的相位相干性。 在不使用用于子载波信号的再生的锁相环的情况下，获得低失真输出。

公开(公告)号：US08717892B2

公开(公告)日：2014-05-06

申请号：US11819744

申请日：2007-06-28

Applicant: Mark Berman ,  Manolito M. Catalasan ,  Bruce Conway ,  Kevin T. Chan

Inventor： Mark Berman ,  Manolito M. Catalasan ,  Bruce Conway ,  Kevin T. Chan

IPC: H04J3/16

CPC classification number: H04L49/101 ,  H04L49/351

Abstract: A programmable channel-swap crossbar switch for swapping signal flow from one channel to another within an Ethernet physical layer device (PHY) is presented. The crossbar switch includes two or more programmed multiplexers, each multiplexer configured to receive two or more input signals and to select which one of the input signals to pass to a programmed corresponding channel, such that a first input signal associated with a first channel can be swapped to a second channel as operating conditions necessitate. The crossbar switch can be used for Ethernet communications with various communication speeds, such as 10BaseT, 100BaseT, and Gigabit communications. A crossbar switch can be used in both a transmit path and a receive path. Two crossbar switches may be used in a receive path in order to undo channel swapping for control signal processing. A method of channel-swapping in an Ethernet PHY communications system is also presented.

Abstract translation: 提出了一种用于在以太网物理层设备（PHY）中交换从一个通道到另一个通道的信号流的可编程通道交换交叉开关。 交叉开关包括两个或多个编程的多路复用器，每个多路复用器被配置为接收两个或更多个输入信号并且选择输入信号中的哪一个传递到编程的对应信道，使得与第一信道相关联的第一输入信号可以是 根据操作条件需要交换到第二个通道。 交叉开关可用于具有各种通信速度的以太网通信，例如10BaseT，100BaseT和千兆位通信。 交叉开关可用于发送路径和接收路径。 可以在接收路径中使用两个交叉开关，以便去除用于控制信号处理的通道交换。 还提出了以太网PHY通信系统中的信道交换方法。

公开(公告)号：US08514992B2

公开(公告)日：2013-08-20

申请号：US13533513

申请日：2012-06-26

Applicant: Kevin T. Chan

Inventor： Kevin T. Chan

IPC: H03D1/04

CPC classification number: H04B3/32 ,  H04B1/586 ,  H04B3/23 ,  H04L12/10

Abstract: An adaptive electronic transmission signal cancellation circuit for separating transmit data from receive data in a bidirectional communication system operating in full duplex mode is disclosed. A transmit signal cancellation circuit is coupled to a transmit signal path and a receive signal path of the communication system, where the transmit signal cancellation circuit is configured to generate a cancellation signal corresponding to a transmit signal. The cancellation circuit is further configured to apply the cancellation signal on the receive signal path for preventing the transmit signal from being asserted to the receive signal path. The cancellation signal comprises a first component and a second component, where the first component represents a mirror image of the transmit signal and the second component represents a direct image of the transmit signal.

Abstract translation: 公开了一种用于在全双工模式下工作的双向通信系统中从发送数据与接收数据分离的自适应电子传输信号消除电路。 发射信号消除电路耦合到通信系统的发射信号路径和接收信号路径，其中发射信号消除电路被配置为产生对应于发射信号的消除信号。 消除电路还被配置为在接收信号路径上应用消除信号，以防止发送信号被断言到接收信号路径。 消除信号包括第一分量和第二分量，其中第一分量表示发射信号的镜像，第二分量表示发射信号的直接图像。