The present invention discloses a signal relay apparatus having frequency calibration mechanism that includes a clock generation circuit, a frequency generation circuit, a clock measuring circuit, a frequency adjusting circuit and a transmission circuit. The clock generation circuit generates a source clock signal. The frequency generation circuit receives the source clock signal and generates a target frequency signal according to a conversion parameter. The clock measuring circuit measures a first frequency offset of a source frequency relative to a first predetermined frequency according to an external reference clock signal. The frequency adjusting circuit adjusts the conversion parameter according to the first frequency offset when the first frequency offset is not within a first predetermined range such that a second frequency offset of a target frequency relative to a second predetermined frequency is within a second predetermined range. The transmission circuit performs signal transmission according to the target frequency signal.

A three-level encoding transmitter is disclosed in which a transmitter circuit is configured to receive an input data signal including binary data and transmit an encoded data signal. The transmitter circuit can include an inverter circuit configured transmit first and second voltages for each logical level of the binary data. A transmission control circuit can cause the inverter circuit to transmit the voltages or deactivate the inverter circuit based on a first control signal. The transmitter circuit can further include an idle circuit configured to transmit an idle voltage between the first and second voltages when there is no data transmission. The idle circuit may transmit the idle voltage based on a second control signal. The first and second control signals may be configured to only be active when the other is inactive.

Provided is a reception circuit that suppresses skew of a waveform of a signal and enables high-speed data communication.

A reception circuit according to the present disclosure includes: a first differential stage that receives a first input signal and a second input signal at a first input unit and a second input unit, respectively, and causes first and second currents corresponding to the first and second input signals, respectively, to flow; a second differential stage including a first current path that generates and outputs a first amplified signal corresponding to the first current and a second current path that generates and outputs a second amplified signal corresponding to the second current; a power supply line that supplies power to the first and second differential stages; and at least one variable resistance unit provided in the first or second current path.

Systems, apparatus and methods are provided for loopback testing techniques for memory controllers. A memory controller that may comprise loopback testing circuitry that may comprise a first multiplexer having a first input coupled to an output of an input buffer and a second input coupled to a first data output from the memory controller, an inverter coupled to the output of the input buffer, and a second multiplexer having a first input coupled to an output of the inverter and a second input coupled to a second data output from the memory controller.

A signaling system includes a pre-emphasizing transmitter and an equalizing receiver coupled to one another via a high-speed signal path. The receiver measures the quality of data conveyed from the transmitter. A controller uses this information and other information to adaptively establish appropriate transmit pre-emphasis and receive equalization settings, e.g. to select the lowest power setting for which the signaling system provides some minimum communication bandwidth without exceeding a desired bit-error rate.

A high-speed serial interface is provided. In one aspect, the high-speed serial interface uses three phase modulation for jointly encoding data and clock information. Accordingly, the need for de-skewing circuitry at the receiving end of the interface is eliminated, resulting in reduced link start-up time and improved link efficiency and power consumption. In one embodiment, the high-speed serial interface uses fewer signal conductors than conventional systems having separate conductors for data and clock information. In another embodiment, the serial interface allows for data to be transmitted at any speed without the receiving end having prior knowledge of the transmission data rate. In another aspect, the high-speed serial interface uses polarity encoded three phase modulation for jointly encoding data and clock information. This further increases the link capacity of the serial interface by allowing for more than one bit to be transmitted in any single baud interval.

System, methods and apparatus are described that facilitate transmission of data, particularly between two devices within an electronic apparatus. Information is transmitted in N-phase polarity encoded symbols. Data is encoded in multi-bit symbols, and the multi-bit symbols are transmitted on a plurality of connectors. The multi-bit symbols may be transmitted by mapping the symbols to a sequence of states of the plurality of connectors, and driving the connectors in accordance with the sequence of states. The timing of the sequence of states is determinable at a receiver at each transition between sequential states. The state of each connector may be defined by polarity and direction of rotation of a multi-phase signal transmitted on the each connector.

Examples include a transmitter module, a receiver module and a communication system for exchanging Ethernet Medium Access Control frames on a single M-LVDS line.

Switch for connecting field apparatuses and device for galvanically isolating at least one apparatus which is connectable to a 2-wire Ethernet bus system includes an uplink and a downlink PHY interface device that each have a transmitting unit and a receiving unit that has two output terminals for providing a received ternary-coded signal as differential signal, includes an uplink and a downlink signal split device that are each connected to the output terminals of an assigned receiving unit and are configured to split a ternary-coded signal provided as differential signal into two binary coded signals, and includes an uplink and a downlink optocoupler device that are each connected to an assigned signal split device and are configured to transfer two received binary-coded signals to a transmitting unit of an assigned PHY interface device.

A bidirectional isolated communication circuit and method for a differential signal. The circuit comprises a first detection circuit used for receiving a first differential pair from a first direction, converting the first differential pair into a first level signal, and inhibiting common-mode interference; a second detection circuit used for receiving a second differential pair from a second direction, converting the second differential pair into a second level signal, and inhibiting common-mode interference; an isolation adjustment circuit used for being provided between the first detection circuit and the second detection circuit and performing communication isolation; and a watchdog circuit used for being awoken according to the first differential pair and/or the second differential pair, and enabling the bidirectional isolated communication circuit to enter from a small current working mode to a normal working mode to perform communication isolation.