Abstract: Circuitry for providing non-uniform analog-to-digital (“A/D”) signal conversion for wideband signals is provided. The circuitry of the invention is optimized for wideband signals because it does not sacrifice the small-scale resolution of high-probability signal amplitudes while preventing the clipping of low-probability signal amplitudes. The circuitry includes a nonlinear amplifier and an A/D converter that may be uniform or non-uniform. The digital output of the A/D converter may be further processed by circuitry that has an output function that is the inverse of that of the nonlinear amplifier, so as to maintain linear A/D conversion.

Abstract: A nonlinear echo compensator compensates for nonlinear echo in a transceiver including a transmitter line driver with current cells that are operated in a Class B operating mode. A mapping circuit generates a pattern dependent driving signal. A coefficient generator generates a compensator coefficient. A canceling circuit communicates with the mapping circuit and the coefficient generator and compensates for nonlinear echo in a received signal based on the pattern dependent driving signal and the compensator coefficient.

Abstract: A cable tester that tests cable and that determines a cable status includes a pretest module that senses activity on pairs of the cable and that selectively enables testing based on the sensed activity. A test module is enabled by the pretest module, transmits a test pulse on one of the pairs, measures a reflection amplitude and calculates a cable length. The cable status includes an open status, a short status, and a normal status. The test module determines the cable status based on the measured amplitude and the calculated cable length. The test module measures received signals on at least one other pair after transmitting the test pulse on the one of the pairs, compares the received signals on the at least one other pair to a predetermined threshold, and determines a pair short status between the one of the pairs and the at least one other pair if the received signals exceed the predetermined threshold.

Abstract: A physical layer device comprises a first port adapted to communicate with one end of a cable. A second port is adapted to communicate with an opposite end of a cable. A cable tester communicates with the first and second ports and selectively tests the cable to determine a cable status, which includes an open status, a short status, and a normal status. The cable tester includes a test module that transmits a test pulse on the cable, measures a reflection amplitude, calculates a cable length, and determines the cable status based on the measured amplitude and the calculated cable length. A frequency synthesizer selectively outputs a plurality of signals at a plurality of frequencies on the first port. An insertion loss calculator that receives the signals on the second port and that estimates insertion loss.

Abstract: A decision-driven control loop wherein a first reconstructed signal is compared to an unreconstructed data symbol signal to initially drive the control loop. A second reconstructed signal that is based on a longer memory path than the first reconstructed signal is evaluated against the first reconstructed signal. The decision-driven control loop is ultimately controlled based on the results of the evaluation between the first and second reconstructed signals. The inventive decision-driven control loop, which may be implemented in software, may form part of a read channel in a storage device.

Abstract: A method of sensing current in an output regulator comprises providing a current sensor having a gain resolution, setting the current sensor gain resolution to an initial resolution, sensing a current flowing through the current sensor, evaluating an amplitude of the current, and at a sampling frequency, controlling the gain resolution of the current sensor based on the evaluating.

Abstract: A physical layer device comprises a first transceiver that selectively communicates with a cable medium. A detector detects a power over Ethernet (POE) device. A switching device selectively provides power from a power supply over the cable medium when the detector detects the POE device. A cable tester communicates with the first transceiver, tests the cable medium and determines a cable status, and delays testing of the cable medium when the detector detects the POE device until the switching device provides the power.

Abstract: A digital controller for controlling a regulated output of an output regulator. The output regulator responsive to a pulse width signal for controlling the transfer of energy between an input source and the regulated output. The digital controller including a duty cycle estimator to determine a nominal duty cycle. An adjust determiner to determine an adjustment value to combine with the nominal duty cycle to generate an adjusted duty cycle. The pulse width signal being a function of the adjusted duty cycle.

Abstract: A digital controller that controls an output regulator includes controller sub-blocks that perform sub-functions of the digital controller, wherein at least one of the controller sub-blocks includes at least one of a delay line and a first comparator. A controller monitors output power states of the output regulator and controls flow of power to the at least one of the controller sub-blocks of the digital controller to reduce power consumption of the digital controller during selected ones of the output power states of the output regulator.

Abstract: A method of controlling deadtime between power switches in an output regulator includes providing at least two power switches having a common node, wherein at least one of the two power switches is a conducting switch and a remainder of the two power switches is a free-wheeling switch, switching one of the conducting switch and the free-wheeling switch from an on-state to an off-state, during a transition from the on-state to the off-state, monitoring a current flowing through one of the conducting switch and the free-wheeling switch, comparing the current to a reference level, and delaying for a predetermined time period, then changing the operating state of the other of the conducting switch and the freewheeling switch from an off-state to an on-state.

Abstract: An output regulator comprises M switch arrays, where M is an integer greater than 2. A controller selectively enables N of the M switch arrays in response to a sense signal. The sense signal is based on an output of the output regulator. The controller generates drive signals to control the N of the M switch arrays, where N is an integer greater than or equal to 0 and less than or equal to M. When N is greater than 0, the controller dynamically sets a phase interval between the N of the M switch arrays to one of greater than 360/N or less than 360/N.

Abstract: A data detection circuit includes a transient detector that senses transient events in data. A first data detector path applies a first equalization target to generate a first bit stream from the data. A second data detector path applies a second equalization target to generate a second bit stream from the data. A baseline correction circuit generates a baseline correction signal using the first bit stream when the transient detector does not sense the transient events and the second bit stream when the transient detector senses the transient events. The first equalization target is a non-DC free equalization target and the second equalization target is a DC-free equalization target. When transients are detected during a sector, the detection circuit continues using the DC-free equalization target until the sector ends.

Abstract: A cable tester tests cable to determine a cable status. A mode selector selects one of a first operating mode and a second operating mode. A pretest module senses activity on the cable and selectively enables testing based on the sensed activity when in the first operating mode and enables testing when in the second operating mode. A test module is enabled by the pretest module, transmits a test pulse on the cable, measures a reflection amplitude and calculates a cable length. The cable status includes an open status, a normal status and a short status. The test module determines the cable status based on the measured amplitude and the calculated cable length.

Abstract: A control system for controlling a multiphase output regulator having a regulated DC output and operating at a switching frequency. The multiphase output regulator including at least two switch arrays to generate individually controllable output phases that combine to form the regulated DC output. The control system comprising a digital controller operable at a sampling frequency greater than the switching frequency. The digital controller responsive to a sense signal corresponding to the regulated output, to generate array duty cycle signals to control each of the switch arrays. The digital controller to control the array duty cycle signals at the sampling frequency and to dynamically set a phase interval between each of the output phases.

Abstract: A receiver for eliminating D.C. noise from a signal received from a communication channel includes an input circuit configured to receive an input signal. The receiver includes an error circuit configured to generate an error signal in accordance with the input signal from the input circuit. The receiver includes a first noise canceler responsive to the error circuit. The first noise canceler is configured to generate a first noise cancellation signal in response to the error signal from the error circuit. The receiver includes a second noise canceler responsive to the error circuit and the first noise canceler. The second noise canceler is configured to generate a second noise cancellation signal from the error signal from the error circuit and the first noise cancellation signal from the first noise canceler. The input circuit is responsive to the second noise cancellation signal from the second noise canceler.

Abstract: A control system comprises a DC/DC converter that includes first and second inductances, that receives a first DC voltage and that generates a second DC voltage. A control module selectively charges or discharges the first inductance while discharging or charging the second inductance during a first mode and one of charges both of the first and second inductances or discharges both of the first and second inductances during a second mode.

Abstract: A cable tester comprises a test initiating module that performs B cable tests. Each of said B cable tests includes selectively transmitting a test pulse on the cable, measuring a reflection amplitude, and calculating a cable length. A test results module determines a cable status for each of said B cable tests based on said measured amplitude and said calculated cable length and that determines an overall cable status of the cable based on the cable at least one of passing and failing A out of B cable tests. A and B are integers greater than zero and B is greater than A.

Abstract: Circuitry for providing non-uniform analog-to-digital (“A/D”) signal conversion for wideband signals is provided. The circuitry of the invention is optimized for wideband signals because it does not sacrifice the small-scale resolution of high-probability signal amplitudes while preventing the clipping of low-probability signal amplitudes. The circuitry includes a nonlinear amplifier and an A/D converter that may be uniform or non-uniform. The digital output of the A/D converter may be further processed by circuitry that has an output function that is the inverse of that of the nonlinear amplifier, so as to maintain linear A/D conversion.

Abstract: A closed-loop control system for a DC/DC converter includes a DC/DC converter that receives a first DC voltage and that generates a second DC voltage. The DC/DC converter includes first and second inductances. A control module receives the second DC voltage and generates at least one control signal to one of charge or discharge the first and second inductances. The control module has first and second modes. During the first mode the control module alternately charges one of the first and second inductances and discharges the other of the first and second inductances. During the second mode the control module one of charges or discharges both of the first and second inductances. The control module initiates the second mode when a transient condition occurs in the DC/DC converter. The transient condition is based on one of the second DC voltage and current through an output capacitance in the DC/DC converter.

Abstract: A physical layer device communicates over a cable and includes a cable tester that determines a cable status, which includes an open status, a short status and a normal status. The cable tester includes a pretest module that senses activity on the cable and selectively enables testing based on the sensed activity. A test module is enabled by the pretest module, transmits a test pulse on the cable, measures a reflection amplitude, calculates a cable length, and determines the cable status based on the measured amplitude and the calculated cable length. A digital signal processor (DSP) communicates with the cable and that has a digital gain parameter. A cable length estimator communicates with the DSP and estimates cable length based on the digital gain parameter.