Abstract: Embodiments of the present invention address deficiencies of the art in respect to via structure utilization in a PCB design and provide a novel and non-obvious method, system and computer program product for impedance discontinuity remediation for via stubs and connectors in a PCB. In one embodiment a method for impedance discontinuity remediation in a PCB can be provided. The method can include configuring a pre-distortion filter to negate an impedance discontinuity in an electrical signal caused by a transmission line with one of a via stub or a connector. The method further can include pre-distortion filtering an electrical signal before transmitting the electrical signal over the transmission line. Finally, the method can include transmitting the pre-distortion filtered electrical signal over the transmission line.

Abstract: An apparatus having reduced noise coupling includes a core layer having an upper and lower surface, the upper and lower surface each including a copper sheet layer, a pre-preg layer having an upper surface and a lower surface, the upper surface of the pre-preg layer coupled to the lower surface of the core layer, a core insulating layer having an upper surface and a lower surface, the upper surface of the core insulating layer coupled to the lower surface of the pre-preg layer, a return current reference layer disposed on the lower surface of the core insulator layer and high-speed signal traces disposed on the upper surface of the core insulating layer, each of the high speed signal traces disposed on a pedestal defined by a section of the pre-preg layer and the core insulating layer, each pedestal being separated by an air gap disposed between adjacent pedestals.

Abstract: A printed circuit board (‘PCB’) with reduced dielectric loss, including conductive traces disposed upon layers of dielectric material, the layers of dielectric material including core layers and prepreg layers, one or more of the layers of dielectric material including pockets of air that reduce an overall relative dielectric constant of the PCB.

Abstract: A cable for high speed data communications that includes a first inner conductor enclosed by a first dielectric layer and a second inner conductor enclosed by a second dielectric layer, the inner conductors and the dielectric layers disposed within the cable in parallel with a longitudinal axis of the cable; drain conductors disposed within the cable laterally to the inner conductors adjacent to the dielectric layers along the longitudinal axis of the cable and within thirty degrees of a horizontal axis through the inner conductors; and a conductive shield composed of a strip of conductive shield material wrapped in a rotational direction along and about the longitudinal axis around the inner conductors, the dielectric layers, and the drain conductors, including overlapped wraps of the conductive shield material along the longitudinal axis.

Abstract: Apparatus and methods for identifying a signal on a printed circuit board (‘PCB’) under test, including an integrated circuit mounted on the PCB, the integrated circuit having a test signal generator that transmits a test signal to an output pin of the integrated circuit, with the output pin connected to a test point on the PCB; the integrated circuit also having signal identification logic that inserts into the test signal, an identifier of the signal; a test probe in contact with the test point; and a signal-identifying controller that receives the test signal and the identifier from the test probe and displays, in dependence upon the identifier, the identity of the signal.

Abstract: A method provides improved signal quality in a computer memory system. In one embodiment, a digital signal is generated having a voltage interpreted with respect to a reference voltage. The reference voltage is dynamically adjusted as a function of the traffic intensity at which the digital signal is directed to a particular receiver. A training phase may be performed for each DIMM of the memory system, to construct a lookup table correlating suitable reference voltages with different traffic intensities. The lookup table may be referenced during a subsequent execution phase, to dynamically select a reference voltage according to changing traffic intensity. The dynamically selected reference voltage value may be enforced by using transistors to selectively recruit resistors of a resistor network.

Abstract: Identifying a signal on a printed circuit board (‘PCB’) under test, including a test probe with a radio transmitter and transmitter antenna, the test probe positioned with the transmitter antenna at a test point on the PCB, the test probe transmitting a radio signal; at least two radio receivers, each receiver having a receiver antenna, each receiver antenna positioned at predetermined, separate physical locations with respect to the PCB, the receivers coupled to at least one signal strength meter, each receiver receiving the transmitted radio signal; and a signal-identifying controller connected to the signal strength meter, the signal-identifying controller reading, from the signal strength meter, signal strengths of the transmitted radio signal as received at the radio receivers; determining, in dependence upon the read signal strengths, a test signal identifier; and displaying the test signal identifier.

Abstract: A system for providing power and ground vias for power distributions systems includes first and second conductive layers on a microelectronic package. The conductive layers may include one or more conductive components such as, but not limited to, power planes, ground planes, pads, traces, and the like for electrically connecting to electronic components. A via may electrically connect the first and second conductive layers. The via may have a cross-section of at least three partially-overlapping shapes. Each of the shapes partially overlaps at least two of the other shapes. The shapes may be, for example, circular, triangular, rectangular, square, polygonal, rhomboidal shape, or any other shape.

Abstract: Measuring control signal timing for synchronous dynamic random access memory (‘SDRAM’), including combining into a trigger signal for an oscilloscope display control signals of an SDRAM under test, the control signals derived only from a single type of memory operations; and driving, continually during both READ and WRITE operations to and from the SDRAM under test, the oscilloscope display with a memory bus data signal (‘DQ’) and a memory bus clock signal (‘DQS’) from the SDRAM under test.

Abstract: A circuit board includes layers, a pair of vias filled with a conductive material and extending through the layers, first and second pairs of conductive signal paths, and holes extending at least partially through the layers and located between the pair of vias. The first pair of conductive paths is connected to the pair of vias within a first layer; the second pair of conductive paths is connected to the pair of vias within a second layer. The pair of vias has a pair of via stubs defined between the second layer and a bottom layer. A differential signal is to be transmitted between the first and second pairs of conductive signal paths via the pair of vias. The holes have a lower dielectric constant than the layers to increase a resonant frequency of the pair of via stubs beyond the frequency of the differential signal.

Abstract: A device and method are disclosed wherein a receiver signal line within an integrated circuit may be selected for probing. In one embodiment, a plurality of signal pads and a test pad are provided on an external surface of an integrated circuit chip. A plurality of signal lines extends through the integrated circuit chip to the signal pads. A multiplexer on the integrated circuit chip is configured for individually selecting any of the signal lines. An amplifier on the integrated circuit chip amplifies a selected signal and communicates the amplified signal to an externally-accessible test pad to be probed.

Abstract: Off-die termination of memory module signal lines in a computer memory subsystem. The computer memory subsystem includes a memory controller and a DIMM socket installed on a PCB. The memory controller is electrically coupled to the DIMM socket via a memory module signal line. Off-die termination includes detecting, by a termination controller installed on the PCB, no presence of a DIMM in the DIMM socket and, responsive to the detection, activating, by the termination controller, an off-die termination component on the PCB to terminate the memory module signal line.

Abstract: Off-die termination module for terminating memory module signal lines in a computer memory subsystem, the computer memory subsystem including a memory controller and a DIMM socket, the memory controller coupled to the DIMM socket via a memory module signal line, the off-die termination module including: an off-die termination component configured to terminate the memory module signal line upon activation; and a spring loaded notch pin implemented as part of the DIMM socket, the spring loaded notch pin configured to toggle activation of the off-die termination component in dependence upon presence of a DIMM in the DIMM socket including activating the off-die termination component upon removal of a DIMM from the DIMM socket and deactivating the off-die termination component upon installation of a DIMM in the DIMM socket.

Abstract: An apparatus, system, and method are disclosed for dynamic phase equalization in a communication channel. A transmitter history module stores a plurality of bits from a data stream that is transmitted through the communication channel. A transmitter detection module detects a pre-transition bit of a first value that is preceded in the data stream by at least one bit of the first value and followed by a transition bit with a second value. A driver module transmits the data stream by driving the communication channel. A transition module pre-drives the communication channel to the second voltage of the transition bit during a bit time interval of the pre-transition bit.

Abstract: In electronic devices with signal traces positioned between a ground layer and a voltage reference layer, systems and methods are provided for connecting a hot pluggable device to the electronic device in a manner that diminishes signal degradation due to parasitic effects. The first device has a second reference layer near the connector that connects to a second device voltage reference layer maintained at a given voltage level across the connector. In the first device near the connector the signal trace is positioned in between a ground layer of the first device and the second reference layer which is maintained at a given voltage by a voltage regulator of the second device. The signal return current travels past the second reference layer to a first reference layer of the first device which is maintained by the first device's voltage regulator through AC decoupling capacitors minimizing the current return path discontinuity.

Abstract: An apparatus, system, and method are disclosed for integrating component testing. A voltage module modifies a reference voltage integral to an electronic device to a plurality of reference voltage values. A test module tests a component of the electronic device at each of the plurality of reference voltage values. In addition, the test module determines a voltage range for the component, wherein the voltage range comprises voltage values between a high voltage failure and a low voltage failure. An optimization module sets the reference voltage value to within the voltage range.

Abstract: A programmable diagnostic memory module provides enhanced testability of memory controller and memory subsystem design. The programmable diagnostic memory module includes an interface for communicating with an external diagnostic system, and the interface is used to transfer commands to the memory module to alter various behaviors of the memory module. The altered behaviors may be changing data streams that are written to the memory module to simulate errors, altering the timing and/or loading of the memory module signals, downloading programs for execution by a processor core within the memory module, changing driver strengths of output signals of the memory module, and manipulating in an analog domain, signals at terminals of the memory module such as injecting noise on power supply connections to the memory module. The memory module may emulate multiple selectable memory module types, and may include a complete storage array to provide standard memory module operation.

Abstract: A method for performing memory diagnostics using a programmable diagnostic memory module provides enhanced testability of memory controller and memory subsystem design. The programmable diagnostic memory module includes an interface for communicating with an external diagnostic system, and the interface is used to transfer commands to the memory module to alter various behaviors of the memory module. The altered behaviors may be changing data streams that are written to the memory module to simulate errors, altering the timing and/or loading of the memory module signals, downloading programs for execution by a processor core within the memory module, changing driver strengths of output signals of the memory module, and manipulating in an analog domain, signals at terminals of the memory module such as injecting noise on power supply connections to the memory module.

Abstract: The present invention assesses memory (DIMM) strength by calculating frequency content of a radiated field which is collected by an apparatus, such as a dipole antenna. Radiated field is created by accelerated charge, which is a function of the slew rate or DIMM strength. Radiated power is directly proportional to the frequency at which bits are driven. By separating the radiated field from the near field or stored field, the DIMM strength content is isolated from other functional DIMM issues, such as tRCD latency, refresh cycles, addressing mode, etc. By examining the radiated power, the disadvantages of the prior art, such as by probing the DIMM's contacts, are avoided.

Abstract: Methods and systems for reducing noise coupling in high-speed digital systems. Exemplary embodiments include a method, including etching a plurality of high speed signal traces onto a core insulating layer, forming trenches on respective sides of the plurality of high speed signal traces, thereby removing insulating material adjacent to the plurality of high speed signal traces and forming pedestals having remaining insulating material, the plurality of high speed signal traces disposed on and coupled to the remaining insulating material, coupling pre-preg material on the high speed signal traces, removing the pre-preg material adjacent the trenches, thereby retaining the pre-preg material aligned with the high speed signal traces, and heating and pressing a core layer to the pre-preg layer, and heating and pressing the pre-preg layer to the core insulating layer.