Abstract: An adaptive equalizer finite impulse response (FIR) filter for high-speed communication channels with modest complexity, where the filter is iteratively updated during a training sequence by a circuit performing the update: h(t+1)= h(t)+?[sgn{d(t)}?sgn{z(t)?Kd(t)}]sgn{ x(t)}, where h(t) is the filter vector representing the filter taps of the FIR filter, x(t) is the data vector representing present and past samples of the received data x(t), d(t) is the desired data used for training, z(t) is the output of the FIR filter, ? determines the memory or window size of the adaptation, and K is a scale factor taking into account practical limitations of the communication channel, receiver, and equalizer. Furthermore, a procedure and circuit structure is provided for calibrating the scale factor K.

Abstract: An adaptive equalizer finite impulse response (FIR) filter for high-speed communication channels with modest complexity, where the filter is iteratively updated during a training sequence by a circuit performing the update: h(t+1)= h(t)+?[sgn{d(t)}?sgn{z(t)?Kd(t)}]sgn{ x(t)}, where h(t) is the filter vector representing the filter taps of the FIR filter, x(t) is the data vector representing present and past samples of the received data x(t), d(t) is the desired data used for training, z(t) is the output of the FIR filter, ? determines the memory or window size of the adaptation, and K is a scale factor taking into account practical limitations of the communication channel, receiver, and equalizer. Furthermore, a procedure and circuit structure is provided for calibrating the scale factor K.

Abstract: In some embodiments, an adaptive filter employs two adaptation modes, where during one adaptation mode the adaptive filter is updated only when the received training sample is a first binary value and during the other adaptation mode the adaptive filter is updated only when the received sample is a second binary value. Each adaptation mode provides a set of filter weights, and these two sets of filter weights are averaged to provide an adapted set of filter weights. The use of two adaptation mode allows for a clock boundary in which the digital portion of the filter operates at a lower clock rate than the analog portion. In other embodiments, a filter architecture is described for providing the algebraic signs of the received data samples, important for sign-sign least means square filtering algorithms. In other embodiments, a filter architecture is described in which efficient use is made of voltage-to-current converters so as to achieve a high throughput rate during filtering.

Abstract: An integrated circuit is provided that includes a first port to receive a first signal from a first channel and a first device coupled to the first port to modify a channel response of the first signal received from the first channel. A waveform capture device may be coupled to the first device to capture a waveform of a signal modified by the first device.

Abstract: A receiver is calibrated using a transmitter that can output a plurality of substantially constant amplitude signals.

Abstract: A clock recovery circuit includes a delay locked loop, and a clock phase interpolator circuit. The delay locked loop provides multiple phases of an input clock signal to the interpolator circuit, which interpolates between two of the clock phases to provide a clock signal at a desired phase. The clock phase interpolator circuit includes selectable differential transistor pairs coupled to variable current sources. Different differential transistor pairs are driven by clock signals of different phases provided by the delay locked loop circuit. Two differential transistor pairs are selected, and currents provided to the selected differential transistor pairs are adjusted to provide an output clock of the desired phase.

Abstract: A device includes a bus, a first transmitter connected to the bus and configured to transmit a first signal over the bus in a first frequency band, a second transmitter connected to the bus and configured to transmit a second signal over the bus in a second frequency band at the same time that the first transmitter is transmitting the first signal, a first receiver connected to the bus and configured to receive the first signal transmitted over the bus in the first frequency band, and a second receiver connected to the bus and configured to receive the second signal transmitted over the bus in the second frequency band. The first frequency band and the second frequency band occupy different portions of the frequency spectrum.

Abstract: In some embodiments, a chip includes a chip interface to accept a delay control signal from outside the chip. The chip also includes a controllable delay line to delay an input signal responsive to the delay control signal to provide an output signal with a particular phase relationship to the input signal. Other embodiments are described and claimed.

Abstract: The invention provides, in an embodiment, an apparatus, method and means for unintrusively observing, echoing and reading signals transmitted by one of a bus and wireless communication, without disturbing electrical properties of the bus, without adding bus latency, and without adding signal discontinuities. In an aspect, a buffer having a trigger is coupled with a component that connects to a memory bus, the buffer echoes signals to an observability port, and a diagnostic device reads the echoed signals. In an aspect, the bus is one of a simultaneous bi-directional (SBD) bus having ternary logic levels, a single ended bus, a differential bus, an optically coupled bus, a chipset bus, a frontside bus, an input/output (I/O) bus, a peripheral component interface (PCI) bus, and an industry standard architecture (ISA) bus. In an aspect, the buffer echoes bus signals having frequencies between 500 MHz. and 5 GHz. In an aspect, the buffer echoes bus signals having frequencies of at least 5 GHz.

Abstract: A method and apparatus for outbound wave subtraction using a variable offset amplifier is described. The method includes calibration of a bi-directional signaling circuit in order to calculate one or more offset codes for cancellation of an outbound wave within a bi-directional communications link. Once the one or more offset codes are calculated, it is determined whether a dual inbound wave is received by the bi-directional signaling circuit. Once received, an offset code from the one or more calculated offset codes is selected according to a value of an outbound wave within the dual inbound/outbound wave. Finally, the outbound wave is cancelled from the dual inbound wave at an output of a variable offset amplifier using the selected offset code.

Abstract: A clock deskew method includes receiving a data signal and a clock signal, processing the data signal to generate a jitter characterization parameter, shifting the clock signal by about 90° from the jitter characterization parameter to generate a sampling clock signal, and sampling the data signal with the sampling clock signal to generate a deskewed data signal. A clock deskew unit includes a clock unit, a sampling unit, and a deskew unit. The deskew unit includes a jitter characterization unit that generates a jitter characterization parameter. The jitter characterization parameter establishes a phase location for aligning a clock signal. Shifting the clock signal by about 90° from the phase location of the jitter characterization parameter provides a location for sampling a data signal to generate a deskewed data signal.

Abstract: A memory device having memory cells supplied with a separate higher voltage power than the separate power supplied to memory logic, and a lower power state that entails removing power from at least some of the logic such that refresh operations to preserve the contents of the memory cells continue to take place, but at least some of the interface to the memory device is powered down to reduce power consumption.

Abstract: In some embodiments, a chip includes first and second ports to provide first and second received data signals and first and second received strobe signal, respectively. An internal clock signal has a fixed phase relationship to the first received strobe signal and the second received strobe signal has an arbitrary phase relationship with the internal clock signal. First and second write blocks latch the first and second received data signals synchronously with the first and second received strobe signals, respectively. Other embodiments are described and claimed.

Abstract: A number of data symbols are driven into a transmission line while simultaneously driving the data symbols into another node. A difference between a signal level from the transmission line and a signal level from the other node while driving the symbols is determined. The difference is applied to a signal input of a variable offset comparator. One of a number of binary values (offset codes) are applied to an offset control input of the comparator, to adjust an implied, variable reference level of the comparator, prior to the comparator performing a comparison between the input signal and the implied reference level.

Abstract: An amplifier includes multiple stages. Early stages of the multi-stage amplifier have low gain and preserve bandwidth.

Abstract: A digital interconnect system transmits pulses across a differential transmission line in response to transitions in an input data signal.

Abstract: In some embodiments, the invention involves a system having a first group of integrated circuits connected in a truncated ring fashion, wherein the truncated ring includes a truncated region to allow for additional integrated circuits to be added to the ring. In some embodiments, the invention involves a system having a group of integrated circuits connected in a pseudo ring fashion, wherein the pseudo ring is created by data flow of bi-directional signaling between the integrated circuits. In some embodiments, the invention involves a system having a group of integrated circuits connected in a pseudo differential arrangement in which multiple conductors carrying signals share a common reference signal conductor.

Abstract: A memory system provides includes multiple memory devices or banks of memory devices that are assigned frequency pass-bands. Each memory device includes frequency translation circuitry to up-convert and down-convert data signals to and from the assigned frequency pass-band. Some embodiments include simultaneous bidirectional communications between memory devices and a controller by assigning multiple frequency pass-bands to each memory device or bank of memory devices. A memory system substrate is provided with bandpass filters between memory device footprints and other device footprints.

Abstract: A port circuit includes circuitry to capture a waveform. The port circuit may be a unidirectional port circuit, or a bidirectional port circuit.

Abstract: In some embodiments, the invention involves a system having a first group of integrated circuits connected in a truncated ring fashion, wherein the truncated ring includes a truncated region to allow for additional integrated circuits to be added to the ring. In some embodiments, the invention involves a system having a group of integrated circuits connected in a pseudo ring fashion, wherein the pseudo ring is created by data flow of bi-directional signaling between the integrated circuits. In some embodiments, the invention involves a system having a group of integrated circuits connected in a pseudo differential arrangement in which multiple conductors carrying signals share a common reference signal conductor.