Abstract: A method, apparatus, and computer instructions for managing a set of signal paths for a chip. A defective signal path within the set of signal paths for the chip is detected. Signals are re-routed through the set of signal paths such that the defective signal path is removed from the set of signal paths and sending signals using remaining data signal paths in the set of signal paths and using an extra signal path in response to detecting the defective signal path.

Abstract: Apparatus and methods are provided for constructing electronic package structures using LGA (land grid array) module-to-board connectors that are designed to provide higher count I/O interconnections by expanding LGA area, but without having to increase chip module footprint or reduce the pitch of area array I/O contacts of an LGA interposer or circuit board beyond practical limits.

Abstract: The present invention relates to computer hardware design, and in particular to a printed circuit board (card) comprising wiring dedicated to supply electric board components such as integrated circuits with at least three different reference planes. In particular at locations, where the pins of a card-to-card connector enter the layer structure of the card discontinuities brake the high frequency signal return path of a given signal wiring. In order to close the signal return path around a signal path from card to card including the connector, and thus to limit the signal coupling while concurrently keeping the card design as simple as possible, it is proposed to provide a) an additional capacitance for a given signal wiring in a discontinuity section, b) wherein the additional capacitance is formed by a voltage island placed within a signal layer located next to the given signal wiring.

Abstract: The present invention relates to computer hardware design and in particular to a printed circuit board comprising wiring dedicated to supply electric board components such as integrated circuits with at least three different reference planes. In order to provide a printed circuit board having an improved signal return path for basically all relevant signal layers at transitions between card, connector, module and chip while still holding the cross-section structure simple, it is proposed to establish a layer structure wherein a) a split voltage plane is located adjacent to one side of one of said reference planes and comprises conducting portions for all of said at least three different voltage levels in respective plane parts, and b) a signal layer being located adjacent to said reference planes.

Abstract: Data busses are configured as N differential channels driven by a data signal and its complement through two off-chip drivers (OCDs). Each OCD is preceded by a programmable delay element and a two way MUX. The two data channels either transmit the data signals or a common clock signal as determined by a select signal from a skew controller. The differential signals are received in a differential receiver and a phase detector. The output of the phase detector in each differential channel is routed through an Nx1 MUX. The Nx1 MUX is controlled by the skew controller. The output of the Nx1 MUX is fed back as a phase error feedback signal to the skew controller. Each differential data channel is sequentially selected and the programmable delays are adjusted until the phase error feedback signal from the selected phase detector reaches a predetermined minimum allowable value. Periodic adjustment may be implemented for calibration.

Abstract: A method of self-synchronizing clocks in a multiple chip system, by assigning one chip as the master chip and the other chips as slave chips. A training signal is sent from master chip to the slave chips to determine the latency from the master chip to a slave chip, and then a synchronization signal is sent out to synchronize the “time zero” of the chips.

Abstract: A clock generator circuit for generating synchronization signals for a multiple chip system. The clock generator circuit comprises generation of a synchronization signal from a reference clock and chip global clock with edge detection logic. In high performance server system design with multiple chips, a common practice for server systems is to use feedback clock and delayed reference clock to generate the synchronization signal. The generated synchronization signal is transferred to latches clocked by the global clock to be used for chip synchronization functions. As the system clock frequency is pushed higher, the phase difference between generated synchronization signal clocked by feedback clock and receiving latch clocked by global clock is becoming such a large portion of cycle time that this signal cannot be transferred deterministically.

Abstract: A system for airflow management in an electronic enclosure includes a backplane assembly having at least one backplane connector, at least one daughter card, and components disposed on the daughter card oriented to facilitate front-to-back airflow, wherein inlet cooling air impinges on the backplane assembly and splits into at least two flow portions flowing in different directions along a surface defining the backplane assembly

Abstract: Described is a method for minimizing switching noise in the high- and mid-frequency range on printed circuit cards or boards by means of a plurality of surface mounted decoupling capacitors. A novel configuration and implementation of capacitor pads including the connecting vias is also presented. As a result the parasitic inductance of the pads and vias can be significantly reduced. Thus the effectiveness of the decoupling capacitors in the mid and high frequency range can be increased, the voltage drop can be reduced and the system performance can be increased. Several design rules for the new pad via configuration lead to the significant reduction of the parasitic inductance. The proposal is especially important for high integrated system designs on boards and cards combined with increased cycle times.

Abstract: Described is a method for minimizing switching noise in the high- and mid-frequency range on printed circuit cards or boards by means of a plurality of surface mounted decoupling capacitors. A novel configuration and implementation of capacitor pads including the connecting vias is also presented. As a result the parasitic inductance of the pads and vias can be significantly reduced. Thus the effectiveness of the decoupling capacitors in the mid and high frequency range can be increased, the voltage drop can be reduced and the system performance can be increased. Several design rules for the new pad via configuration lead to the significant reduction of the parasitic inductance. The proposal is especially important for high integrated system designs on boards and cards combined with increased cycle times.