Abstract: This invention concerns a novel Viterbi decoding apparatus and method in which a survivor path unit (SPU) implements the traceback method with a RAM which stores path information in a manner which allows fast read access without requiring physical partitioning of the RAM. This results in an implementation that requires less chip area than conventional solutions.

Abstract: The present invention presents a calibrator for a mobile station of a TDMA wireless communications system such that the calibrator calibrates a low-frequency clock to a high frequency clock locked to system timing. When the mobile station is in idle mode (i.e., listening to a paging channel periodically, but otherwise taking no action), the control processor commands the mobile station to enter into sleep mode to minimize power consumption. During sleep mode, the high-frequency reference clock and all clocks derived from it are turned off. Only the calibrated low-frequency clock remains operating to clock the sleep logic.

Abstract: In a redundant server network system, failover services for a failed server are provided by a survivor server belonging to a common failover group. At startup of a local server process running on the survivor server, a context is created for the local server and for each remote server belonging to the same failover group as the local server. At startup the context of the local server is also activated. The local server process is configured to operate on and make decisions based upon activated contexts. Each context includes server specific configuration and control information. When the survivor server must provide failover services for a failed server belonging to its same failover group, the context corresponding to the failed remote server is activated.

Abstract: A method and apparatus for providing loop coherency between a multiplicity of nodes. The disclosed technique and apparatus utilize a primary loop for nominal data communications and a normally unutilized secondary loop. A loop coherency circuit detects a loop incoherency condition which results in a interruption of the primary loop. The loop coherency circuit reroutes the flow of data to a secondary loop segment and back to a primary loop segment to provide a continuous coherent arbitrated loop.

Abstract: A preconditioning mechanism for preconditioning a polishing pad is described. The preconditioning mechanism includes an arm capable of being disposed over the polishing pad and a head section located on a distal end of the arm and rotatable about a central axis. Furthermore, the head section includes at least two heads oriented about the central axis and have surfaces for either conditioning or preconditioning the polishing pad, whereby rotation of the head section about the central axis by defined amounts presents at least two heads to the polishing pad so that different of the two heads can engage the polishing pad for conditioning or preconditioning depending upon how far rotation has proceeded.

Abstract: A novel device for pole splitting which can be employed in multistage amplifiers having a final stage and a prior stage. The device comprises a first capacitor connected between the output of the prior stage and the output of the final stage, a source follower, and a second capacitor connected between the output of the prior stage and the source follower. The source follower provides an offset voltage that reduces variation of the total capacitance of the first and second capacitors. In a preferred version of the present invention, the first and second capacitor each comprise a MOSFET transistor having a certain threshold voltage. The offset voltage is set to be at least the threshold voltage of the MOSFET transistors. In a preferred version, the source follower comprises a plurality of MOSFET transistors, which includes a MOSFET transistor having a gate connected to the first capacitor and a source connected to the second capacitor.

Abstract: A method and system for preventing smoke and fire damage in a clean room within which a tool including an electrically powered element is located. The method includes the step of providing the tool with a system including a fire proof housing, a sensor, an environmental sealing mechanism, an operator panel and a controller. The fire proof housing is secured over the tool and includes a door and at least one port to the tool. The sensor monitors an environmental condition within the housing and generates a sensor signal. The environmental sealing mechanism seals the at least one port and the door to the housing in response to the control signals to render the housing environmentally sealed. The operator panel includes visual indicators responsive to actuation signals. The controller is adapted to receive and process the sensor signals and to execute a shutdown control sequence during which the control signals and the actuation signals are generated.

Abstract: A device and method for characterizing signal skew between a first signal and a second signal. The device includes a delay chain and a first transition detector in communication with the delay chain. The first transition detector is configured for receiving the first signal and provides a pulse signal to the delay chain upon detecting a transition of the first signal. The device includes a second transition detector which is in communication with a latch and is configured for receiving the second signal. The second transition detector sets the latch upon detecting a transition of the second signal. At least one pass gate is connected to the delay chain and the latch. At least one timing latch is connected to the pass gate for receiving signal skew information between the first and second signals.

Abstract: A gate array cell architecture is provided with routing tracks at variable track pitches, thereby increasing the density of the architecture. Orientation of the devices in the gate cells perpendicularly to the routing tracks in the second metallization layer provides an increased porosity in this layer. The orientation allows an N channel device to be made smaller than a P channel device within a gate cell, to provide balanced devices. The perpendicular orientation also provides more contact points for source or drain. When the mulitple contacts are used to connect the device to a power source, the multiple contacts reduce the effective resistance and increase the reliability of the devices.

Abstract: A die is unpackaged from a Chip on Tape by grinding off molding compound from an upper surface of the COT until the COT's leads are evenly exposed across the upper surface, selectively etching out the leads using the remaining molding compound as a mask, removing an underlying layer of gold plating, and then removing the remaining molding compound. The unpacked die can then be reframed with new leads and molding compound for failure analysis and electrical failure verification.

Abstract: A receiver is described for recovering digital data from a transmitted balanced signal where the balanced signal includes a first plurality of pulses, each pulse having a first pulse width. The receiver includes an input circuit, a buffer circuit, and a calibration circuit. The input circuit receives the transmitted signal and includes a first differential amplifier for amplifying a first signal, a second differential amplifier for amplifying a second signal, and a converter for receiving the amplified first signal and amplified second signal and then generating a third signal. The first and second signals are included within the transmitted signal. The buffer circuit receives and buffers the third signal, and outputs a fourth signal including a second plurality of pulses which have a second plurality of pulse widths. The calibration circuit receives the fourth signal.

Abstract: An integrated circuit includes a plurality of solder balls arrayed on the bottom surface of a package of the integrated circuit. These solder balls provide for surface mounting of the integrated circuit to a circuit board by solder reflow. The array of solder balls can be planarized so that each of the plural solder balls participate in defining a truly planar solder ball contact array for the integrated circuit package. Methods of manufacturing the integrated circuit with a package having planarized solder balls in an array dependent from a bottom surface thereof are set forth. The truly planarized solder ball contact array of the integrated circuit package affords nearly absolute reliability in forming of surface-mount electrical connections between the integrated circuit package and the circuit board on which the package is to mount.

Abstract: A low threshold voltage MOS device on a semiconductor substrate is disclosed. The substrate has an upper surface, and a first well region is disposed in said semiconductor substrate extending downwardly from the semiconductor substrate upper surface. The first well region includes a dopant of a first conductivity type having a first average dopant concentration. Source and drain regions of a second conductivity type are laterally spaced from each other and are disposed in the first well region, the source and drain regions extending downwardly from the semiconductor substrate upper surface a predetermined distance. A channel region comprising the first well region of the first conductivity type is disposed between the source and drain regions. The channel region also extends at least the predetermined distance below the semiconductor substrate upper surface.

Abstract: A process and resulting product are disclosed for an integrated circuit structure including two or more metal wiring levels interconnected by metal-filled vias. A first insulation layer, such as an oxide layer, is formed over a first metal wiring level on an integrated circuit structure. A via mask layer, such as a nitride mask layer, is then formed over the insulation layer with openings formed in the via mask layer in registry with portions of the underlying metal wiring to which it is desired to make electrical contact by the formation of vias through the first insulation layer. A second insulation layer, which may comprise a second oxide layer, is then formed over the mask layer. A reverse second metal wiring level mask, such as a photoresist mask or another nitride mask, is then formed over the second insulation layer to define the second metal wiring. The second insulation layer is then anisotropically etched with an etchant which is selective to the second level metal wiring mask and the via mask, i.e.

Abstract: An instruction (also called a "bit reversal instruction") for reversing the order of bits in an input signal is implemented by reusing one or more components in a datapath normally found in a processor. Specifically, a bit reversal instruction is implemented by reuse of a shifter unit normally used in a datapath to shift bits of an input signal. The shifter unit includes three stages: a first stage formed by a number of input multiplexers, a second stage formed by, for example, a left shifter, and a third stage formed by a number of output multiplexers. When using a left shifter to implement the bit reversal instruction, the input multiplexers are not used. Instead, the left shifter is used to shift bits of the input signal left by a number that is inverse of the number of bits to be reversed. Thereafter, the output multiplexers reverse the order of bits generated by the left shifter, thereby completing the bit reversal instruction.

Abstract: A test method for a memory device wherein failures that may only occur under specified worst-case conditions are converted to hard functional failures. These locations are subsequently detected and remapped by built-in self test (BIST) and built-in self-repair (BISR) circuitry. First, a test suite is performed on a memory array which includes redundant row and column locations. Typically, this test suite is performed under conditions which are most likely to induce failure. Row and column locations that are determined to be malfunctioning are scanned out of the memory device, along with the number of available redundant rows and columns. If there are sufficient redundant locations, the failing rows and columns are permanently disabled by blowing each of the corresponding fuse links. When power is subsequently applied to the memory device, BIST will detect rows and columns, including those permanently disabled, with hard functional failures. Accesses to these locations may then be redirected by BISR circuitry.

Abstract: A computer system and method for generating a hardware description language source code file with embedded microcode segments for describing control logic of a complex digital system. A macro file is defined, comprising source code written in the hardware description language and a macro name associated with a segment of the source microcode in the macro file. A skeleton file is defined, comprising source code written in the hardware description language and including a reference to the macro name. The skeleton file is combined with the segment of the source microcode from the macro file at the reference to the macro name using a preprocessor to form a final source code file. Preferably, each microcode segment is encapsulated between a pair of comment statements expressed in the hardware description language.

Abstract: A phase locked loop, which does not require a local reference clock to obtain a frequency lock. The circuit includes a frequency locked loop and a phase locked loop in which the frequency locked loop does not require a local reference clock. The frequency locked loop includes a transition counter having an input for data with an output connected to a charge pump. This charge pump is connected to a loop filter, which in turn is connected to a voltage controlled oscillator. The output of the voltage controlled oscillator is connected to a second input in the transition counter. The phase locked loop includes a phase detector with an input for data. The output of this phase detector is connected to a second charge pump, which has it output connected to the loop filter. The output of the voltage controlled oscillator also is connected to the input of the phase detector.

Abstract: An automated endpoint detection process includes obtaining a baseline graph of reflected radiation signal versus time of radiation exposure for a standard integrated circuit substrate surface that is substantially free of residual metal, directing radiation generated from a radiation source through a radiation transparent region of a polishing pad such that radiation is incident on at least a portion of a surface of the integrated circuit substrate, detecting a reflected radiation signal from the integrated circuit substrate surface through the radiation transparent region of the polishing pad, comparing an area under a graph of the reflected radiation signal versus time of radiation exposure obtained for the integrated circuit surface to the baseline graph of the standard integrated circuit substrate surface and thereby determining whether residual metal is present on the surface of the integrated circuit substrate and signaling the chemical-mechanical polishing assembly to stop polishing after polishing for

Abstract: Microprocessor main programs and their interrupt handling routines are written in a high level programming language such as C. Each is compiled separately, and each is compiled invoking a compiler option which commands the compiler to not use a given set of registers in the compiled code. Post-processing is then performed on the compiled interrupt code to replace accesses to a first set of registers with accesses to the given set of registers. The result is that while both the main program and the interrupt handler were written in C, the compiled code for each employs different registers. This allows context switching from the main program to the interrupt handler and back again with almost none of the overhead traditionally associated with context switching register save and restore operations during exception handling.