Abstract: Apparatus, methods, and systems for filtering for power line communications are described. In one example, a low pass filter for power line communication in a power system including at least one phase conductor and a neutral conductor is described. The filter includes at least one capacitor coupled between the phase conductor and the neutral conductor, at least one resistor coupled between the phase conductor and the neutral conductor, and at least one inductor coupled on the neutral conductor.

Abstract: A XDSL line card including an allocator for allocating power to the multi-tone modulated communications on each of the subscriber lines, and for selecting control parameters sufficient to effect communications on each of the subscriber lines at a power level proximate to an allocated power level therefore. The line card also includes configurable components coupled to one another to form a transmit path and a receive path to couple to the digital subscriber lines. The configurable components are responsive to the control parameters selected by the allocator to initialize multi-tone communications over each of the plurality of subscriber lines at a power level proximate the allocated power level.

Abstract: A XDSL line card including an allocator for allocating power to the multi-tone modulated communications on each of the subscriber lines, and for selecting control parameters sufficient to effect communications on each of the subscriber lines at a power level proximate to an allocated power level therefore. The line card also includes configurable components coupled to one another to form a transmit path and a receive path to couple to the digital subscriber lines. The configurable components are responsive to the control parameters selected by the allocator to initialize multi-tone communications over each of the plurality of subscriber lines at a power level proximate the allocated power level.

Abstract: An improved line driver-hybrid and method for increasing the power efficiency, signal accuracy, and stability of a transmit signal on a transmission line are disclosed. The improved line driver-hybrid uses a negative feedback control loop, thereby enhancing operational stability and suppressing both amplifier imperfections and discrete component manufacturing variances. Furthermore, the improved line driver-hybrid provides a power efficient full duplex solution for line driver applications. The present invention can also be viewed as providing a method for actively terminating a transmission line.

Abstract: An improved method and apparatus for active line termination is disclosed. An active termination line driver (ATLD) includes a pair of power amplifiers configured to amplify a transmit signal, the amplifiers comprise a first input for receiving the transmit signal, a second input for receiving a feedback signal, and an output configured to provide the amplified transmit signal to the load. The ATLD also includes a resistive network configured to provide the feedback signal from the outputs of the amplifiers to the second inputs power amplifiers. The resistive network is selectively configured to facilitate any one of a plurality of feedback configurations to emulate a back-matching impedance. Other embodiments of the present invention may be construed as methods for power efficiently driving a transmit signal to a load.

Abstract: A line driver is disclosed. Generally, the structure of the line driver contains an amplifier stage that can operate at various voltage levels. The first external supply voltage is connected to a first power supply input of the amplifier stage. The line driver also includes a charge pump that generates at least a first internal supply voltage supplied to the amplifier stage. A switch control circuit is also included within the line driver to regulate the voltage output from the charge pump. Systems and methods for supplying various voltages to a load are also disclosed.