Abstract: Methods implementable in a computer system for simulating the transmission of signals across a plurality of data channels (bus) are disclosed. The disclosed techniques simulate the effects of Intersymbol Interference (ISI), cross talk, and Simultaneous Switching Output (SSO) noise by generating Probability Distribution Functions (PDFs) for each. The resulting PDFs are convolved to arrive at a total PDF indicative of the reception of data subject to each of these non-idealities. The total PDF, and its underlying terms, can be indexed to particular channels of the bus as well as to particular logic states. Use of the disclosed technique allows bit error rates and sensing margins to be determined with minimal computation and simulation.

Abstract: Apparatuses, multi-chip modules, capacitive chips, and methods of providing capacitance to a power supply voltage in a multi-chip module are disclosed. In an example multi-chip module, a signal distribution component may be configured to provide a power supply voltage. A capacitive chip may be coupled to the signal distribution component and include a plurality of capacitive units. The capacitive chip may be configured to provide a capacitance to the power supply voltage. The plurality of capacitive units may be formed from memory cell capacitors.

Abstract: Apparatuses and methods for driving input data signals onto signal lines as output data signals are disclosed. An example apparatus includes a detection circuit, a driver adjust circuit, and a data driver. The detection circuit is configured to detect a characteristic(s) of a group of input data signals to be driven onto adjacent signal lines. A characteristic could be, for example, a particular combination of logic levels and/or transitions for, the group of input data signals. The driver adjust circuit is configured to provide a driver adjustment signal based at least in part on a detection signal, that is provided by the detection circuit. A data driver is configured to drive a respective one of the group of input data signals as a respective one of the output data signals, wherein the data driver is adjusted based at least in part on the driver adjustment signal.

Abstract: Apparatus are disclosed, such as those involving a transmitter circuit that is configured to generate multi-level signals based on a plurality of data digits. One such transmitter circuit includes a signal output and an encoder configured to provide control signals based at least partially on the plurality of data digits. The transmitter circuit also includes a first set of switches configured to receive one or more of the control signals, and to selectively conduct a first or second voltage reference to the signal output. The transmitter circuit further includes first and second voltage drop circuits that provide third and fourth voltage references, respectively. The third and fourth voltage references have voltage levels between those of the first and second voltage references. The transmitter circuit also includes a second set of switches configured to receive one or more of the control signals, and selectively conduct the third or fourth voltage reference to the signal output.

Abstract: Embodiments of the invention comprise a continuous-time equalizer for reducing ISI in data received from a communication channel, and methods and circuitry for tuning or calibrating that equalizer. Selected coefficients for a transfer function of the equalizer circuit are fixed, while other coefficients are tuned by an adaptive algorithm. The adaptive algorithm minimizes errors associated with the tunable coefficients based on one or more training signals sent by the transmitter and received by the equalizer circuit at the receiver. The training signals allow for a variety of error terms to be calculated, from which the tunable coefficients are updated so as to iteratively minimize the error terms and simultaneously tune the equalizer to more accurately compensate for the degrading effects of the channel.

Abstract: Apparatuses and methods for driving input data signals onto signal lines as output data signals are disclosed. An example apparatus includes a detection circuit, a driver adjust circuit, and a data driver. The detection circuit is configured to detect a characteristic(s) of a group of input data signals to be driven onto adjacent signal lines. A characteristic could be, for example, a particular combination of logic levels and/or transitions for, the group of input data signals. The driver adjust circuit is configured to provide a driver adjustment signal based at least in part on a detection signal, that is provided by the detection circuit. A data driver is configured to drive a respective one of the group of input data signals as a respective one of the output data signals, wherein the data driver is adjusted based at least in part on the driver adjustment signal.

Abstract: Apparatus and methods related to data transmission are disclosed. One such apparatus includes a transmitter, a receiver, and a channel. The transmitter includes a pair of current sources and a pair of switches. Each of the switches conducts one of the current sources to the channel in response to input data. The receiver includes a first node configured to receive a signal over the channel. The receiver also includes a resistance generating a voltage drop between the first node and a second node. The receiver further includes a first transistor and a second transistor that are together configured to provide a voltage level to the second node based at least partly on the voltage drop. The resistance provides a negative feedback to center the mean signal level, thereby reducing intersymbol interference.

Abstract: Methods and apparatus are disclosed, such as those involving mixed-mode signaling that includes transmitting a differential signal and a common mode signals over the same pair of interconnect traces. One such apparatus includes a first transmitter configured to transmit a differential signal through a pair of electrically conductive lines in a first direction. The differential signal has a first frequency and carries electronic data. The apparatus further includes a second transmitter configured to transmit a common mode signal through the pair of electrically conductive lines in the first direction. The common mode signal is superimposed onto each of the differential signal. The common mode signal has a second frequency that is lower than the first frequency and carries a control signal. This configuration reduces the number of lines and pins on electronic circuits, thereby saving space thereon.

Abstract: Methods and apparatus to transfer data between a first device and a second device, is disclosed. An apparatus according to various embodiments may comprise a first device and a second device. The first device may comprise at least one first non-differential transmitter coupled to a first channel, at least one second non-differential transmitter coupled to a second channel, and at least one differential receiver to receive a data bit and its complement on the first and second channels in parallel. The second device may comprise at least one first non-differential receiver coupled to the first channel, at least one second non-differential receiver coupled to the second channel, and at least one differential transmitter to transmit a data bit and its complement on the first and second channels in parallel.

Abstract: A receiver for receiving a reduced swing signal from a transmission channel is disclosed, in which the swing of the reduced swing signal is less than the power supply of the receiver and possibly is less than the power supply of the transmitter. The receiver comprises a level shifter for offsetting the reduced swing signal, and an amplifier which receives both the reduced swing signal and its offset to produce a full swing signal output referenced to the power supply of the receiver. The full swing signal can thereafter be buffered, and eventually can be captured by a clock. Optionally, the disclosed reduced swing receiver also contains calibration circuitry for improving the integrity of the full swing signal output, and in particular for countering the effects of process, and in some embodiments temperature, variations, which alter the characteristics of the transistors which make up the receiver circuitry.

Abstract: Methods and apparatus disclosed herein operate to receive a plurality of cycles characterized by a set of time-domain aspects, to modify at least one of the time-domain aspects of at least some of the plurality of cycles to produce a plurality of modified cycles, to process at least some of the modified cycles to produce time-domain cycles, and to create a time-domain signal based at least in part on concatenating the time-domain cycles.

Abstract: Apparatus are disclosed, such as those involving a 3-D integrated circuit. One such apparatus includes a first die including a plurality of vertical connectors formed therethrough. The apparatus also includes a first circuit configured to encode multiple data bits into a multi-bit symbol, and provide the multi-bit symbol to two or more of the vertical connectors. The apparatus further includes a second circuit configured to receive the multi-bit symbol from at least one of the two or more vertical connectors, and decode the multi-bit symbol into the multiple data bits. The apparatus provides enhanced repairability with no or less redundant vertical connectors, thus avoiding the need for “on the fly” or field repair of defective vertical connectors.

Abstract: Methods and circuitry for lowering the capacitance of interconnects, particularly Through Wafer Interconnects (TWIs), using signal level adjustment are disclosed. Embodiments of the invention seek to bias the midpoint voltage level of the signals on the TWIs towards inversion, where at high frequencies capacitance is at its minimum. In one embodiment, reduced swing signals are used for the data states transmitted across the TWIs, in which the reduced swing signals use a midpoint voltage level tending to bias the TWI capacitance towards inversion. In another embodiment, signals are AC coupled to the TWI where they are referenced to an explicit bias voltage directly connected to the TWI. This allows signals to propagate through the TWI while the TWI is biased towards inversion. In a third embodiment, the potential of the substrate is explicitly lowered with respect to the TWI potential.

Abstract: The use of asymmetric signalling over channels is disclosed. Pursuant to one or more embodiments of the invention, the channels in the parallel bus operate as standard non-differential interconnects for data travelling in one direction through the bus, and operate as differential interconnects for data travelling in the other direction through the bus. So that data capacity of the bus remains the same in both directions, the data rate during differential transmission can be twice that of the data rate during standard transmissions. Asymmetric signalling can also occur over two unidirectional busses of channels to the same effect.

Abstract: Methods for generating realistic waveforms with controllable voltage noise and timing jitter in a computer-based simulation environment and the simulation of a subset of those waveforms with system elements along the signal path is disclosed. By deriving a generic, re-useable, parameterized Fourier series, time-domain clock and pseudo-random data signals are generated from a subset of their true harmonic components. Time-domain signal parameters including high, low, and common-mode voltage levels, transition slew-rates, transition timing, period and/or frequency, may be designated by the user, and the computer calculates the harmonic components that will combine through the inverse Fourier transform to provide the required time-domain characteristics. By computing the frequency content of the signal directly it is possible to simulate the interaction of the signal with various system blocks while remaining in the frequency domain, thereby reducing simulation time and memory requirements.

Abstract: Apparatus are disclosed, such as those involving a 3-D integrated circuit. One such apparatus includes a first die including a plurality of vertical connectors formed therethrough. The apparatus also includes a first circuit configured to encode multiple data bits into a multi-bit symbol, and provide the multi-bit symbol to two or more of the vertical connectors. The apparatus further includes a second circuit configured to receive the multi-bit symbol from at least one of the two or more vertical connectors, and decode the multi-bit symbol into the multiple data bits. The apparatus provides enhanced repairability with no or less redundant vertical connectors, thus avoiding the need for “on the fly” or field repair of defective vertical connectors.

Abstract: Apparatus and methods are disclosed, such as those involving data transmission. One such apparatus includes a transmitter, a receiver, and a channel. The transmitter includes a pair of current sources and a pair of switches. Each of the pair of switches conducts one of the current sources to the channel in response to input data. The receiver includes a first node configured to receive a signal over the channel, and a second node. The receiver also includes a resistance generating a voltage drop between the first node and the second node. The receiver further includes a first transistor of a first type and a second transistor of a second type. The first and second transistors are together configured to provide a voltage level to the second node based at least partly on the voltage drop. The resistance provides a negative feedback to center the mean signal level, thereby reducing intersymbol interference.

Abstract: One or more embodiments are disclosed that involve computer implementable techniques for generating simulate-able waveforms without the need for repeatedly including and simulating a full channel model or testing the waveforms on a physical channel. Techniques according to such embodiments the invention comprise simulating the sending of a waveform across a channel and recording deviations from a simulated received waveform, which comprise differences between the ideal waveform as sent and the simulated received waveform. These deviations are then used to create simulate-able waveforms, which include the effects of noise and jitter, without the need for additional channel simulation. As an alternative to using channel simulation, deviations may also be collected from sending a waveform across a physical channel.

Abstract: Disclosed herein are circuitry and methods for transmitting data across a parallel bus using both high common mode and low common mode signaling. The transmitter stages are configured to work with two of three possible power supply voltages: a high Vddq voltage, a low Vssq voltage, and an intermediate Vx voltage. In one embodiment, the odd numbered transmitter stages, that drive the odd numbered outputs to the bus, use the Vddq and Vx supplies, such that the odd numbered outputs comprise high common mode signals. The even numbered transmitter stages, that drive the even numbered outputs to the bus, use the Vx and Vssq supplies, such that the even numbered outputs comprise low common mode signals.

Abstract: Computer-implementable recursive summation algorithms are disclosed that are useful for efficiently performing recursive convolution, such as is often required in Statistical Signal Analysis (SSA) techniques. The disclosed recursive summation algorithms can be more computationally-efficient from both a speed and memory perspective than other recursive convolution techniques known in the prior art, such as the techniques relying on Fast Fourier Transforms (FFTs).