Abstract: A method of operating a transceiver integrated circuit is disclosed. The method comprises generating test signals directed to testing one or more transceiver parameters. The test signals are transmitted from a digital domain to an analog domain along a transmit path, and looped-back from the transmit path to a receive path. Echo canceller circuitry coupled between the transmit path and the receive path is trained and generates a filtered output representing a metric indicative of the one or more transceiver parameters.

Abstract: A method of operation in an ethernet receiver circuit is disclosed. The method comprises sampling an input signal to generate a sampled signal having a sampled noise component and a sampled data component. The sampled signal is sliced, and a slicer error determined based on the slicing of the sampled signal. A subsequently sampled noise component is filtered based on the slicer error.

Abstract: Systems and methods are described for radio frequency (RF) calibration in a multiple antenna system (MAS) with multi-user (MU) transmissions (“MU-MAS”) exploiting uplink/downlink channel reciprocity. The RF calibration is used to compute open-loop downlink precoder based on uplink channel estimates, thereby avoiding feedback overhead for channel state information as in closed-loop schemes. For example, a MU-MAS of one embodiment comprises a wireless cellular network with one or multiple beacon stations, multiple client devices and multiple distributed antennas operating cooperatively via precoding methods to eliminate inter-client interference and increase network capacity.

Abstract: A method of operating a transceiver integrated circuit is disclosed. The method comprises generating test signals directed to testing one or more transceiver parameters. The test signals are transmitted from a digital domain to an analog domain along a transmit path, and looped-back from the transmit path to a receive path. Echo canceller circuitry coupled between the transmit path and the receive path is trained and generates a filtered output representing a metric indicative of the one or more transceiver parameters.

Abstract: In one embodiment, a method for determining capacitive signature validity of a powered device (PD) attached to power sourcing equipment (PSE) having (i) an isolated side with a primary coil and (ii) a line side with a secondary coil connected to the PD. The method includes determining, on the isolated side, a first time T1 and a corresponding first voltage V1 across the PD. Then generating, on the isolated side, a switching signal used to generate an electrical current through the primary coil. Then determining, on the isolated side, a second time T2 and a corresponding second voltage V2 across the PD, wherein a difference between V2 and V1 is related to the electrical current provided to the primary coil. Then determining the capacitive-signature validity of the PD based on T1, T2, V1, V2, and a resistive signature of the PD.

Abstract: Disclosed is a current mode switched power supply. The current mode switched power supply includes a switching element and a power stage coupled to the switching element and configured to provide, in response to the switching of the switching element, an output voltage and a feedback voltage related to the output voltage. The current mode switched power supply also includes a digital control circuit connected to the switching element to digitally control the switching of the switching element.

Abstract: One embodiment monitors a line-side electrical current provided by a power sourcing equipment (PSE) port to a powered device (PD), the PSE port having a power-isolation transformer with a primary coil on an isolated side and a secondary coil on a line side. A switching signal having a switching period and a duty cycle is applied to the primary coil of the power-isolation transformer. A value is determined for an electrical current on the isolated side of the power-isolation transformer, conversion is performed between a line-side electrical current value Iout and a corresponding isolated-side peak-current value Ipeak, and the line-side electrical current is indirectly monitored based on the determined isolated-side current value.

Abstract: A virus detection mechanism is described in which virus detection is provided by a network integrated protection (NIP) adapter. The NIP adapter checks incoming media data prior to it being activated by a computing device. The NIP adapter operates independently of a host processor to receive information packets from a network. This attribute of independence allows NIP anti-virus (AV) techniques to be “always on” scanning incoming messages and data transfers. By being independent of but closely coupled to the host processor, complex detection techniques, such as using check summing or pattern matching, can be efficiently implemented on the NIP adapter without involving central processor resources and time consuming mass storage accesses. The NIP adapter may be further enhanced with a unique fading memory (FM) facility to allow for a flexible and economical implementation of polymorphic virus detection.

Abstract: Disclosed is a current mode switched power supply. The current mode switched power supply includes a switching element and a power stage coupled to the switching element and configured to provide, in response to the switching of the switching element, an output voltage and a feedback voltage related to the output voltage. The current mode switched power supply also includes a digital control circuit connected to the switching element to digitally control the switching of the switching element.

Abstract: Disclosed is a method and apparatus that includes a power supply having a primary coil and a secondary coil. The secondary coil generates an output voltage and a feedback voltage related to the output voltage. The feedback voltage is sampled at a time instant that is digitally controllable. The output voltage is determined from the feedback voltage.

Abstract: In one embodiment, a load connected to power sourcing equipment (PSE) compatible with a Power over Ethernet (PoE) standard is characterized to determine whether the load corresponds to a valid powered device (PD). A switching signal having a first frequency is generated on the isolated side and used to generate an electrical current through the isolated-side primary coil of a power transformer in the PSE. A first voltage measurement, corresponding to a first line-side voltage across the transformer's secondary coil, is generated on the isolated side, e.g., using an isolated-side auxiliary transformer coil. The load is characterized based on the first voltage measurement and the first frequency. To compensate for voltage offset, a second voltage measurement can be generated corresponding to a second frequency of the switching signal, where the load is then characterized based on the first and second voltage measurements and frequencies.

Abstract: Disclosed is a current mode switched power supply. The current mode switched power supply includes a switching element and a power stage coupled to the switching element and configured to provide, in response to the switching of the switching element, an output voltage and a feedback voltage related to the output voltage. The current mode switched power supply also includes a digital control circuit connected to the switching element to digitally control the switching of the switching element.

Abstract: Disclosed is a method and apparatus that includes a power supply having a primary coil and a secondary coil. The secondary coil generates an output voltage and a feedback voltage related to the output voltage. The feedback voltage is sampled at a time instant that is digitally controllable. The output voltage is determined from the feedback voltage.

Abstract: Disclosed is a method and apparatus that includes a power supply having a primary coil and a secondary coil. The secondary coil generates an output voltage and a feedback voltage related to the output voltage. The feedback voltage is sampled at a time instant that is digitally controllable. The output voltage is determined from the feedback voltage.

Abstract: In one embodiment, a load connected to power sourcing equipment (PSE) compatible with a Power over Ethernet (PoE) standard is characterized to determine whether the load corresponds to a valid powered device (PD). A switching signal having a first frequency is generated on the isolated side and used to generate an electrical current through the isolated-side primary coil of a power transformer in the PSE. A first voltage measurement, corresponding to a first line-side voltage across the transformer's secondary coil, is generated on the isolated side, e.g., using an isolated-side auxiliary transformer coil. The load is characterized based on the first voltage measurement and the first frequency. To compensate for voltage offset, a second voltage measurement can be generated corresponding to a second frequency of the switching signal, where the load is then characterized based on the first and second voltage measurements and frequencies.

Abstract: In one embodiment, a method for determining capacitive signature validity of a powered device (PD) attached to power sourcing equipment (PSE) having (i) an isolated side with a primary coil and (ii) a line side with a secondary coil connected to the PD. The method includes determining, on the isolated side, a first time T1 and a corresponding first voltage V1 across the PD. Then generating, on the isolated side, a switching signal used to generate an electrical current through the primary coil. Then determining, on the isolated side, a second time T2 and a corresponding second voltage V2 across the PD, wherein a difference between V2 and V1 is related to the electrical current provided to the primary coil. Then determining the capacitive-signature validity of the PD based on T1, T2, V1, V2, and a resistive signature of the PD.

Abstract: One embodiment monitors a line-side electrical current provided by a power sourcing equipment (PSE) port to a powered device (PD), the PSE port having a power-isolation transformer with a primary coil on an isolated side and a secondary coil on a line side. A switching signal having a switching period and a duty cycle is applied to the primary coil of the power-isolation transformer. A value is determined for an electrical current on the isolated side of the power-isolation transformer, conversion is performed between a line-side electrical current value Iout and a corresponding isolated-side peak-current value Ipeak, and the line-side electrical current is indirectly monitored based on the determined isolated-side current value.

Abstract: Disclosed is a method and apparatus that includes a power supply having a primary coil and a secondary coil. The secondary coil generates an output voltage and a feedback voltage related to the output voltage. The feedback voltage is sampled at a time instant that is digitally controllable. The output voltage is determined from the feedback voltage.

Abstract: Disclosed is a current mode switched power supply. The current mode switched power supply includes a switching element and a power stage coupled to the switching element and configured to provide, in response to the switching of the switching element, an output voltage and a feedback voltage related to the output voltage. The current mode switched power supply also includes a digital control circuit connected to the switching element to digitally control the switching of the switching element.

Abstract: A digitally programmable analog receive-side channel equalizer includes N identical zero-positioning (ZP) circuit pairs in a cascade, where the transfer function of one ZP circuit of each pair exhibits a positive zero and the transfer function of the other ZP circuit exhibits a negative zero. By digitally controlling tunable capacitors within the pairs, the equalizer's frequency response and gain can be adjusted, while a controllable (e.g., constant) group delay is maintained. The number of blocks in the cascade can be selected, and each block independently configured, to optimally compensate for high-frequency losses in a wide range of transmission environments. One implementation involves a T-block cascade with output taps that feed a T:1 output selector such that the output of the overall equalizer can be selected to be any one of these taps corresponding to a programmable equalizer of effective length N where N?T.