A high-speed signaling system with adaptive transmit pre-emphasis. A transmit circuit has a plurality of output drivers to output a first signal onto a signal path. A receive circuit is coupled to receive the first signal via the signal path and configured to generate an indication of whether the first signal exceeds a threshold level. A first threshold control circuit is coupled to receive the indication from the receive circuit and configured to adjust the threshold level according to whether the first signal exceeds the threshold level. A drive strength control circuit is coupled to receive the indication from the receive circuit and configured to adjust a drive strength of at least one output driver of the plurality of output drivers according to whether the first signal exceeds the threshold level.

The present disclosure relates to systems and methods for transmitting data in a video signal. The systems may perform the methods to generate a data frame, wherein the data frame may include at least a frame header and frame data, the frame header may include at least one autocorrelation and cross-correlation sequence; insert the data frame into an area of a video signal, wherein the inserted area of the video signal is not an area of line and field synchronization or an area of effective video; transmit the video signal having the data frame to another device.

A system and method for efficiently transporting data in a computing system are contemplated. In various embodiments, a computing system includes a source, a destination and multiple lanes between them for transporting data. Multiple receivers in the destination has a respective termination resistor connected to a single integrating capacitor, which provides a reference voltage to the multiple receivers. The receivers reconstruct the received data by comparing the corresponding input signals to the reference voltage. The source includes a table storing code words. The source maps a generated data word to a code word, which is sent to the destination. The destination maps the received code word to the data word. The values of the code words are selected to maintain a nearly same number of Boolean ones on the multiple lanes over time as a number of Boolean zeroes.

Systems and methods for improving the efficiency of a rotational dynamic element matching (DEM) for Delta Sigma converters. In some implementations, the systems and methods are provided for reducing intersymbol interference (ISI) of a Delta Sigma converter. A delta sigma converter architecture can include multiple I-DACs, and the output from each I-DAC can vary from the other l-DACs. Techniques include decreasing mismatch among multiple l-DACs while improving efficiency of rotational dynamic element matching.

Systems and methods for improving the efficiency of a rotational dynamic element matching (DEM) for Delta Sigma converters. In some implementations, the systems and methods are provided a for reducing intersymbol interference (ISI) of a Delta Sigma converter. A delta sigma converter architecture can include multiple I-DACs, and the output from each I-DAC can vary from the other I-DACs. Techniques are disclosed for decreasing mismatch among multiple I-DACs while improving efficiency of rotational dynamic element matching.

A driver circuit includes digital inputs, such as a first digital input and a second digital input. The digital inputs receive voltages at either a digital high-voltage or a digital low-voltage. The driver circuit has a clock input, an analog output, a first differential pair of transistors connected to the analog output, second differential pairs of transistors connected to the analog output, and voltage limiters connected to the clock input and the second differential pairs of transistors. The voltage limiters supply different voltages to the second differential pairs of transistors, which results in the second differential pairs of transistors providing analog signals to the analog output that are at different voltage steps at, and between, the digital high-voltage and the digital low-voltage.

Methods and systems are described for receiving symbols of a codeword via wires of a multi-wire bus, the codeword representing an aggregate sum of a plurality of sub-channel constituent codewords, each sub-channel constituent codeword representing a weight applied to an associated sub-channel vector of a plurality of sub-channel vectors of an orthogonal matrix, generating a plurality of comparator outputs using a plurality of common-mode resistant multi-input comparators (MICs), each common-mode resistant MIC having a set of input coefficients representing a corresponding sub-channel vector of the plurality of sub-channel vectors, each sub-channel vector (i) mutually orthogonal and (ii) orthogonal to a common-mode sub-channel vector, outputting a set of forward-channel output bits formed based on the plurality of comparator outputs, obtaining a sequence of reverse-channel bits, and transmitting the sequence of reverse-channel bits by sequentially transmitting common-mode codewords over the wires of the multi-wire bus.

A memory interface may include a transmitter that generates multi-level signals. The transmitter may employ channel equalization to improve the quality and robustness of the multi-level signals. The channel equalization may be controlled independently from the drive strength of the multi-level signals. For example, a first control signal may control the de-emphasis or pre-emphasis applied to a multi-level signal and a second control signal may control the drive strength of the multi-level signal. The first control signal may control a channel equalization driver circuit and the second control signal may control a driver circuit.

A memory interface may include a transmitter that generates multi-level signals made up of symbols that convey multiple bits of data. The transmitter may include a first data path for a first bit (e.g., a least significant bit (LSB)) in a symbol and a second data path for a second bit (e.g., the most significant bit (MSB)) in the symbol. Each path may include a de-emphasis or pre-emphasis buffer circuit that inverts and delays signals received at the de-emphasis or pre-emphasis buffer circuit. The delayed and inverted data signals may control de-emphasis or pre-emphasis drivers that are configured to apply de-emphasis or pre-emphasis to a multi-level signal.

A driver circuit includes digital inputs, such as a first digital input and a second digital input. The digital inputs receive voltages at either a digital high-voltage or a digital low-voltage. The driver circuit has a clock input, an analog output, a first differential pair of transistors connected to the analog output, second differential pairs of transistors connected to the analog output, and voltage limiters connected to the clock input and the second differential pairs of transistors. The voltage limiters supply different voltages to the second differential pairs of transistors, which results in the second differential pairs of transistors providing analog signals to the analog output that are at different voltage steps at, and between, the digital high-voltage and the digital low-voltage.