Described are on-die termination (ODT) systems and methods that facilitate high-speed communication between a driver die and a receiver die interconnected via one or more signal transmission lines. An ODT control system in accordance with one embodiment calibrates and maintains termination resistances and drive currents to produce optimal output swing voltages. Comparison circuitry employed to calibrate the reference resistance is also used to calibrate the drive current. Termination elements in some embodiments are divided into two adjustable resistive portions, both of which are designed to minimize capacitive loading. One portion is optimized to produce a relatively high range of adjustment, while the other is optimized for fine-tuning and glitch-free switching.

The present invention provides a transmitter including a first variable resistor, a first transistor, a second transistor, a third transistor and a fourth transistor is disclosed. The first variable resistor is coupled between a supply voltage and a first node. A first electrode of the first transistor is coupled to the first node, and a second electrode of the first transistor is coupled to a first output terminal of the transmitter. A first electrode of the second transistor is coupled to the first output terminal of the transmitter, and a second electrode of the second transistor is coupled to a second node. A first electrode of the third/fourth transistor is coupled to the first node, and a second electrode of the third/fourth transistor is coupled to a second output terminal of the transmitter.

Disclosed is a driver of an ethernet transmitter and a control method therefor. The driver has a first output port and a second output port connected to an ethernet receiver through a transmission line, and comprises: a signal conversion module for converting differential current signals into a first voltage signal and a second voltage signal; a first driving module adjusting a swing of the first voltage signal, to obtain a first output signal having a voltage equal to the first voltage signal; a second driving module adjusting a swing of the second voltage signal, to obtain a second output signal having a voltage equal to the second voltage signal. An architecture having a relatively small area is realized, and the ethernet transmitter meets the requirement on a large output swing in 10BASE-T mode.

A phase shifter includes functional actively controlled phase-shift elements formed with TSVs. The phase shifter may include plural phase shifter elements each including: a signal line including a signal line through-substrate-via (TSV) in a substrate; a ground return line including a ground return line TSV in the substrate; a capacitance control line including a capacitance control line TSV in the substrate; and an inductance control line including an inductance control line TSV in the substrate, wherein the phase shifter element has one of a first phase shift and a second phase shift, different from the first phase shift, based on a capacitance and an inductance of the signal line TSV.

A differential communication circuit is connected to a communication line formed of a positive communication line and a negative communication line for differential communication. The differential communication circuit includes: a series circuit that includes a resistor element and a connection switch. The resistor element is connected between the positive and negative communication lines when the connection switch is turned on. The circuit also includes a transmission unit that is configured to output a differential signal to the communication line and a controller that is configured to change impedance of the communication line by turning on the connection switch in a period during which the transmission unit does not output the differential signal.

A transmitting/receiving device for a bus system and a method for reducing an oscillation tendency in the transition between different bit states. The transmitting/receiving device has a transmitting stage for transmitting a transmission signal to a first bus wire of a bus of the bus system and for transmitting the transmission signal as an inverse signal to a second bus wire of the bus, and an asymmetry reduction module for reducing an asymmetry of bus signals arising in the bus wires. The asymmetry reduction module includes a polarity reversing diode, whose cathode is connected to the cathode of a reverse polarity diode of the transmitting stage. The asymmetry reduction module switches a potential of the cathode of the polarity reversing diode to a potential that is greater than or equal to a level of a recessive bus state.

An integrated circuit for generating an equalized signal, according to a channel, from serial data includes a shift register that extracts a symbol sequence from the serial data. A data storage stores values of an equalized digital signal corresponding to potential symbol sequences corresponding to a filter coefficient sequence. A lookup table outputs the equalized digital signal of a value corresponding to the extracted symbol sequence. A digital-to-analog converter (DAC) converts the equalized digital signal into the equalized signal. A controller refreshes the lookup table, based on at least one of values stored in the data storage and values included in the lookup table, in response to a control signal.

Various embodiments relate to a transmit driver circuit, including: a first node connected to a first differential output; a first transistor connected in series with a first resistor, wherein the series connected first transistor and first resistor are connected between a source voltage and the first node; a second transistor connected in series with a second resistor, wherein the series connected second transistor and second resistor are connected between the first node and a ground; a second node connected to a second differential output; a third transistor connected in series with a third resistor, wherein the series connected third transistor and third resistor are connected between the source voltage and the second node; a fourth transistor connected in series with a fourth resistor, wherein the series connected fourth transistor and fourth resistor are connected between the second node and the ground; a first differential input connected to the gate of the first transistor and the gate of the fourth transistor; and a second differential input connected to the gate of the second transistor and the gate of the third transistor, wherein the first transistor, second transistor, third transistor, and fourth transistor are NMOS transistors.

Methods, systems, and apparatuses related to memory operation with common clock signals are provided. A memory device or system that includes one or more memory devices may be operable with a common clock signal without a delay from switching on-die termination on or off. For example, a memory device may comprise first impedance adjustment circuitry configured to provide a first impedance to a received clock signal having a clock impedance and second impedance adjustment circuitry configured to provide a second impedance to the received clock signal. The first impedance and the second impedance may be configured to provide a combined impedance about equal to the clock impedance when the first impedance adjustment circuitry and the second impedance adjustment circuitry are connected to the received clock signal in parallel.

In a transmission device connected by AC coupling, time taken before the start of transmission of valid data is shortened. The transmission device includes an internal resistor, an internal circuit, and a transmission-side control unit. One end of the internal resistor is connected to an output terminal connected to a capacitor. The internal circuit supplies one of a plurality of potentials different from each other to another end of the internal resistor. The transmission-side control unit performs control to supply one of the plurality of potentials to the internal circuit over a period from time when a potential of the output terminal is initialized to a predetermined initial value to timing when the potential of the output terminal reaches a predetermined specified value.