Abstract: A ramp-stack chip package is described. This chip package includes a vertical stack of semiconductor dies or chips that are offset from each other in a horizontal direction, thereby defining a terrace with exposed pads. A high-bandwidth ramp component, which is positioned approximately parallel to the terrace, is electrically and mechanically coupled to the exposed pads. For example, the ramp component may be coupled to the semiconductor dies using: solder, microsprings and/or an anisotropic conducting film. Furthermore, each of the semiconductor dies includes a static bend so that an end segment of each of the semiconductor dies is parallel to the direction and is mechanically coupled to the ramp component. These end segments may facilitate high-bandwidth communication of signals between the chips and the ramp component, for example, via proximity communication.

Abstract: An integrated circuit containing a communication channel is described. This communication channel includes a transmit circuit configured to transmit signals using a voltage-mode driver, a receive circuit, and a capacitive link that couples the transmit circuit to the receive circuit. The communication channel includes a filter with a capacitive-summing junction to equalize signals communicated between the transmit circuit and the receive circuit.

Abstract: A ramp-stack chip package is described. This chip package includes a vertical stack of semiconductor dies or chips that are offset from each other in a horizontal direction, thereby defining a stepped terrace. A high-bandwidth ramp component, which is positioned approximately parallel to the stepped terrace, is mechanically coupled to the semiconductor dies. Furthermore, the ramp component includes an optical waveguide that conveys the optical signal, and an optical coupling component that optically couples the optical signal to one of the semiconductor dies, thereby facilitating high-bandwidth communication of the optical signal between the semiconductor die and the ramp component.

Abstract: An assembly component and a technique for assembling a chip package using the assembly component are described. This chip package includes a set of semiconductor dies that are arranged in a stack in a vertical direction, which are offset from each other in a horizontal direction to define a stepped terraced at one side of the vertical stack. Moreover, the chip package may be assembled using the assembly component. In particular, the assembly component may include a housing having another stepped terrace. This other stepped terrace may include a sequence of steps in the vertical direction, which are offset from each other in the horizontal direction. Furthermore, the housing may be configured to mate with the set of semiconductor dies such that the set of semiconductor dies are arranged in the stack in the vertical direction. For example, the other stepped terrace may approximately be a mirror image of the stepped terrace.

Abstract: A repeater circuit, such as a clock regeneration and multiplication circuit, is described. In this repeater circuit, a clock multiplier unit (CMU) generates an internal clock signal based on a forwarded clock signal, which is received on a link. Furthermore, a phase interpolator (PI) in the repeater circuit provides the output clock signal based on the forwarded clock signal and the internal clock signal. Note that the CMU and the PI filter reduce the cycle-to-cycle jitter in the forwarded clock signal and the internal clock signal, and that the output clock signal has a phase that is a weighted average of the phases of the forwarded clock signal and the internal clock signal. In addition, the relative weights of the forwarded clock signal and the internal clock signal (i.e., the amount of phase averaging and jitter filtering) may be adjusted based on a position or location on the link.

Abstract: A method for calibrating an offset voltage of an amplifier used to amplify capacitively coupled communication signals is described. During this process, a common voltage is applied to one or more inputs to the amplifier. Next, an output of the amplifier is iteratively, measured, and charge is applied to the one or more inputs until the offset voltage is less than a pre-determined value. Note that applying the charge may involve applying a sequence of one or more charge pulses.

Abstract: A system and method is disclosed for controlling signal conditioning parameters and a sampling parameter controlling conversion of a received signal to digital sampled values prior to decoding. The sampled values are decoded according to a comparison with expected values calculated according to a model of a transmission channel. The model is also updated from time to time by comparing the expected values with actual sampled values. Variation of the expected values over time is calculated. One or more of the signal conditioning parameters and the sampling parameter are adjusted according to a numerical minimization method such that the system BER is reduced.

Abstract: A device includes a semiconductor die having a surface, a plurality of proximity connectors proximate to the surface, and a circuit coupled to at least one of the plurality of proximity connectors. The semiconductor die is configured to communicate voltage-mode signals through capacitive coupling using one or more of the plurality of proximity connectors. The circuit also includes a filter with a capacitive-summing junction to equalize the signals.

Abstract: A diversity proximity communication system formed on two juxtaposed chips, one having a two-dimensional array of transmit elements, the other having a two-dimensional array of receive elements. The receive and transmit elements need not be aligned and may have nominal alignment of one transmit element overlapping the corners of four receive elements. The elements may be electrical pads capacitively coupled across the interface. Signals of four different multiplexing groups, e.g., time-multiplexed, are supplied to transmitting elements in a 2×2 array. Signals from four receive elements in a 2×2 array are amplified, combined, and demultiplexed for the selected multiplexing group. The gains for the four signals to be combined are differentially controlled to increase the signal-to-noise ratio. The amplification may be determined by the overlap between each of the receive elements and the transmit element of the selected multiplexing group.

Abstract: Embodiments of a circuit for use with an inter-chip connection that has a variable complex impedance (which can be conductive, capacitive or both), a system that includes the circuit, and a communication technique are described. This inter-chip connection may be formed between a microspring or an anisotropic film and a metal connector on or proximate to a surface of a chip. Moreover, the circuit may mitigate signal distortion associated with the variable complex impedance. For example, the circuit may include an internal impedance that is electrically coupled in series with the metal connector, and that has an impedance which dominates the variable complex impedance over a range of operating frequencies. Separately or additionally, the circuit may be adapted to correct for the signal distortion.

Abstract: One embodiment of the present invention provides a system that reduces power consumption by using capacitive coupling to perform a majority detection operation. The system starts by driving a plurality of signals onto a plurality of driven wires. The signals are then fed from each driven wire through a corresponding coupling capacitor to a single majority detection wire. Next, the system feeds signal on the majority detection wire and a bias voltage to a differential receiver. The output of the differential receiver switches if the signal on the majority-detection wire switches relative to the bias voltage. The system then uses the output of the differential receiver to optimize the signals from the plurality of driven wires for transmission across a long signal route. Optimizing the transmission of signals reduces the power consumed by the computer system.

Abstract: In a proximity communication system, transmit elements on one chip are aligned with receive elements on a second chip juxtaposed with the first chip. However, if the elements are misaligned, either statically or dynamically, the coupling between chips is degraded. The misalignment may be compensated by controllably degrading performance of the system. For example, the transmit signal strength may be increased. The bit period or the time period for biasing each bit may be increased, thereby decreasing the bandwidth. Multiple coupling elements, such as capacitors, may be ganged together, thereby decreasing the number of channels. The granularity of symbols, such as images, may be increased by decreasing the number of bits per symbol. Multiple coupling elements, such as capacitors, may be ganged together, thereby decreasing the number of channels.

Abstract: A memory device with increased communication bandwidth is described. In this memory device, control logic routes data signals from a memory array using inactive bitlines in response to a read command. These data signals are then placed on an adjacent unused input/output (I/O) line or routing channel, as opposed to a proximate I/O line that is in use. For example, unused bitlines located on the top and bottom of the memory array may be used to route data signals to adjacent local I/O lines. In particular, the data signals can be placed on unused local I/O lines which are associated with adjacent bitline sense amplifiers. The resulting increased communication bandwidth can overcome the constraints imposed by the limited number of local I/O lines in the memory device without appreciably increasing the chip size, power consumption, or cost.

Abstract: A simulation apparatus and method is provided for simulating complex high speed interconnects for which closed forms of the S-parameter are incorporated. Differential transmission lines are represented in a causal manner analytically using the 4-port S-parameter without concerns of passivity and stability. Difficult discontinuities of interconnect such as differential vias are represented in closed form and the present invention allows those interconnects to be characterized by 4-port S-parameter measurements or simulation. A complete method of combining causal transmission line models with discontinuities in cascade is provided.

Abstract: Some embodiments of the present invention provide techniques and systems for high-bandwidth on-chip communication. During operation, the system receives an input voltage signal which is to be transmitted over a wire in a chip. The system then generates one or more modified voltage signals from the input voltage signal. Next, the system drives each of the voltage signals (i.e., the input voltage signal and the one or more modified voltage signals) through a respective capacitor. The system then combines the output signals from the capacitors to obtain a combined voltage signal. Next, the system transmits the combined voltage signal over the wire. The transmitted signals can then be received by a hysteresis receiver which is coupled to the wire through a coupling capacitor.

Abstract: A phase-interpolator circuit is described. In the phase-interpolator circuit, an output signal, having a fundamental frequency and a phase, is generated based on a weighted summation of a first reference signal and a second reference signal, where the first reference signal has the fundamental frequency and a first phase, and the second reference signal has the same fundamental frequency and a second phase. Note that contributions of the first reference signal and the second reference signal, respectively, to the output signal are determined based on associated first and second impedance values in a weighting circuit in the phase-interpolator circuit. For example, a programmable capacitance ratio of two capacitors may be used to interpolate between the first reference signal and the second reference signal.

Abstract: One embodiment of the present invention provides a system that reduces power consumption by using capacitive coupling to perform a majority detection operation. The system starts by driving a plurality of signals onto a plurality of driven wires. The signals are then fed from each driven wire through a corresponding coupling capacitor to a single majority detection wire. Next, the system feeds signal on the majority detection wire and a bias voltage to a differential receiver. The output of the differential receiver switches if the signal on the majority-detection wire switches relative to the bias voltage. The system then uses the output of the differential receiver to optimize the signals from the plurality of driven wires for transmission across a long signal route. Optimizing the transmission of signals reduces the power consumed by the computer system.

Abstract: A multi-chip module (MCM) is described in which at least two substrates are mechanically coupled by an adhesive layer that maintains alignment and a zero (or near zero) spacing between proximity connectors on surfaces of the substrates, thereby facilitating high signal quality during proximity communication between the substrates. In order to provide sufficient shear strength, the adhesive layer has a thickness that is larger than the spacing. This may be accomplished using one or more positive and/or negative features on the substrates. For example, the adhesive may be bonded to: one of the surfaces and an inner surface of a channel that is recessed below the other surface; inner surfaces of channels that are recessed below both of the surfaces; or both of the surfaces. In this last case, the zero (or near zero) spacing may be achieved by disposing proximity connectors on a mesa that protrudes above at least one of the substrate surfaces.

Abstract: In a proximity communication system, transmit elements on one chip are aligned with receive elements on a second chip juxtaposed with the first chip. However, if the elements are misaligned, either statically or dynamically, the coupling between chips is degraded. The misalignment may be compensated by controllably degrading performance of the system. For example, the transmit signal strength may be increased. The bit period or the time period for biasing each bit may be increased, thereby decreasing the bandwidth. Multiple coupling elements, such as capacitors, may be ganged together, thereby decreasing the number of channels. The granularity of symbols, such as images, may be increased by decreasing the number of bits per symbol.

Abstract: A system of protecting a proximity communication system against electrostatic discharge (ESD). The proximity communication system includes two chips, each having an array of electrical pads at its surface and covered by a thin dielectric layer such that capacitive coupling circuits are formed between the chips when they are joined together. In at least one of the chips, an additional protection pad is formed away from the array, and heavy protection circuitry is connected to it. Its surface is exposed through the dielectric surface over it such that, when an ESD aggressor approaches, the discharge occurs to the protection pad.