Abstract: Test jig apparatus for testing an integrated circuit chip that suppresses build-up and subsequent discharge of electrical charge on the test jig apparatus or on the chip. The test jig apparatus includes a base of selected material having a top surface of the same general shape and dimensions as the chip to be tested. Preferably, the entire top surface of the base is electrically grounded. The base has two or more side surfaces with side surface planes that are approximately perpendicular to a plane defining the top surface of the base. Each side surface accepts a side plate, made of a selected material such as ULTIM, that can be attached to or removed from the base. The side plate material resists electrical charge buildup and subsequent discharge so that the chip being tested is not subjected to electrical discharge from this source. In another embodiment, the side plates are replaced by plates mounted on the top surface of the base.

Abstract: A digital computer system having a "smart" cache controller that permits the system to take advantage of CPU address pipelining while minimizing the performance impact of a pipelined cache read miss in a system with a relatively low hit ratio such as a direct mapped cache.

Abstract: An I/O buffer is provided that is noise-isolated, i.e., less susceptible to the effect of switching noise. In particular, a noise isolated I/O buffer includes an output terminal, a transient switching circuit connected to first power and ground voltage sources, to a logic input signal and to the output terminal, and a logic holding circuit connected to second power and ground voltage sources separate from the first power ground voltage sources, to the logic input signal and to the output terminal. The transient switching circuit causes a logic level of the output terminal to be switched responsive to a change in the input signal. The logic holding circuit causes the logic level of the output terminal to be maintained in the absence of a change in the input signal. In the absence of a change in the input signal, the transient switching circuit may be turned off, therefore presenting a high impedance to the first power and ground voltage sources.

Abstract: A test fixture for use in the testing of integrated circuit devices includes a metal conductive base plate mounted on a printed circuit wiring board. The base plate has holes extending through it between its upper and lower surfaces. An electrically conductive metal floating plate is resiliently biased upward to a normal position spaced a short distance above the upper surface of the base plate. The floating plate has holes through it which mate with and correspond to the holes through the base plate. Insulating sleeves, with spring pin connectors inside, are placed in the holes in the base plate and these sleeves extend upwardly above the surface of the base plate to a height not greater than the sum of the thickness of the base plate and of the thickness of the floating plate.

Abstract: A method for making an integrated circuit in accordance with the present invention comprises fabricating at least one functional MOSFET with a hot electron resistant structure including a lightly doped drain, fabricating at least one output MOSFET with an ESD resistant structure including a gate means without associated spacers, and electrically coupling at least one functional MOSFET to at least one output MOSFET. An integrated circuit structure in accordance with the present invention includes at least one functional MOSFET having a hot electron resistant structure including a LDD drain, at least one output MOSFET having an ESD resistant structure including a gate means without associated spacers, and means for electrically coupling the two together. The functional MOSFET includes a gate insulator, a conductive gate region over the gate insulator, spacers along the sidewalls of the gate insulator and conductive gate regions, a pair of LDD regions, and source/drain regions.

Abstract: Lead systems of the subject invention include "coplanar leads" and "aplanar leads", which differ in structure at the inner bond finger. Coplanar leads are generally planar along the lead body and the inner bond finger. Aplanar leads are bent or deformed at the inner bond finger, such that the inner bond finger terminus is not in the plane of the lead body but instead is above or below the plane of the lead body. Deforming select inner bond fingers out of the general plane of the lead system provides a spatial separation for the bonding wires which are attached to the inner bond fingers. This spatial separation acts to minimize wire crossing and shorting during fill processes and results in improved semiconductor package yield.

Abstract: An apparatus dynamically decodes memory addresses while supporting memory map options that require different memory bits which are dependent upon the memory address. A current CPU address or an address stored in an expanded memory specification (EMS) register is selected as the defining address. This defining address is then decoded by one of twenty-five (25) memory map options available. The resultant decoded signal drives select lines of a multiplexer whose output drives memory address lines to on-board banks of DRAMS.

Abstract: Chip capacitors are attached to an integrated circuit package. Strips of synthetic tape are placed between pairs of chip capacitor pads on the integrated circuit package. The strips of synthetic tape each have a height extending above height of the pairs of chip capacitor pads. In the preferred embodiment, the strips of synthetic tape are strips of polyimide tape. The height of the strips of synthetic tape is selected so that the chip capacitors will be installed at a sufficient distance from the integrated circuit package so that solder balls will not be of sufficient diameter to wedge between the integrated circuit package and the chip capacitors. The chip capacitors are installed over the pairs of chip capacitor pads. The chip capacitors rest on the strips of synthetic tape. For example, the chip capacitors are permanently attached to the pairs of chip capacitors using a solder process. A reflow solder process is then performed.

Abstract: The amount of user configuration required for a programmable DRAM interface controller is minimized while assuring adherence to DRAM signal specifications and providing improved DRAM memory transfer performance using a novel intelligent programmable DRAM interface controller which allows programming of TRAS, TRP, TRCD, TCP, TCAS and TCST in units of the cpu clock/2 while obtaining TCSH and TRSH specifications without explicitly programming these parameters. THE TCSH specification is accomplished by holding CAS from deasserting until RAS has deasserted or until the RAS programmed low time has been met. The TRSH specification is accomplished by holding RAS asserted in all normal read or write accesses for at least one time unit after CAS has been asserted, which, in a majority of CPU/DRAM Systems, insures that the DRAM limitation TRSH is satisfied.

Abstract: A process for forming a stress relief layer on a semiconductor die and the resulting structure of the process is described. The stress relief layer is formed on a surface of a die which has already been attached to a die attach pad of a lead frame by a cured epoxy. The purpose of the layer is to act as a stress relief buffer by relieving the die surface from contraction forces created by a plastic material used for encapsulating the die and die attach pad portion of the lead frame, as the plastic material cools following hot injection molding of the material to form the encapsulation. Prior to application of the stress relief material onto the surface of the die, the surface is cleaned to restore its high surface energy. The stress relief material is formed by diluting a silicone compound with a non-reactive diluent such as a silicone oil so that both the surface energy and viscosity of the silicone compound is reduced.

Abstract: A synchronizing means is provided for synchronizing an asynchronous interrupt signal to a synchronous clock signal for a computer system or the like. The synchronizing means includes a plurality of latch subsystems, where each of the latch subsystems has a sample input terminal for receiving a synchronous clock signal and a hold terminal for receiving a complementary synchronous clock signal. Set logic means are provided for generating a set output signal in response to certain predetermined output signals of the synchronizing means having a predetermined relationship therebetween, which occurs when an input interrupt signal has a duration greater than 1.5 periods of the synchronous clock signal. The set logic means includes AND gates and OR gates. Reset logic means are provided for generating a reset output signal. The reset logic means includes AND gates and OR gates.

Abstract: A method and apparatus for detecting the presence of gaseous impurities, notably oxygen, in a gas mixture that flows over an IC wafer in an etcher during the etching process. The method is based upon the discovery that the ratio of the etch rate of spin-on-glass material to the etch rate of other materials, such as plasma-enhanced chemical vapor deposition (PECVD oxide) materials, varies in a predictable manner with the amount of oxygen contaminating the gas mixture. The standard ratio, in the absence of oxygen, is determined for a given set of processing conditions by first etching an SOG wafer, then etching a PECVD oxide material wafer, measuring the amount of material etched in each case, and from that calculating the respective etch rates, and finally taking the ratio of the two calculated etch rates. This standard ratio is used as the benchmark for future tests.

Abstract: A digital computer system including a memory subsystem thereof for increasing the throughput of the digital computer system is disclosed, comprising a central processing unit (CPU), a main memory, and a Look-ahead Instruction Prefetch Buffer (LIPB) external to the CPU for prefetching at least one portion of instruction code from the main memory each time the CPU initiates a request for instruction code from the main memory and for accelerating the submission of the portion of instruction code to said CPU means upon request by said CPU means without a memory system delay that is usually required when accessing a larger number of memory locations in the main memory each time the CPU initiates an instruction code request.

Abstract: A ring-style, multi-stage VCO of a phase lock loop circuit includes two or more differential amplifier stages. The phase lock loop includes a lowpass filter connected between a control voltage terminal and a voltage-to-current converter stage, which includes a first source-follower MOS transistor M1 with a source resistor R1 and a diode-connected MOS transistor M2 connected to its drain terminal. A current-source MOS transistor M8 has a gate terminal connected to the drain of the first MOS transistor M1 such that the transistor M8 mirrors current of transistor M1. A diode-connected transistor M9 has its gate terminal and its drain terminal connected together and also to the drain terminal of transistor M8. A differential amplifier stage includes a current-source MOS transistor M10 having a gate terminal connected to the drain of the first MOS transistor M1 to current mirror the drain current of M1.

Abstract: An apparatus and method for placing the die of a die-down configured integrated circuit package in an upright orientation. The first board has electrical receptors peripherally surrounding a first hole formed through the first board. A die-down configured integrated circuit package with the die thereof exposed is inserted into a test socket having a second hole formed through the bottom thereof. The exposed die is located over the second hole in the bottom surface of the test socket. The test socket is placed onto the top surface of the first board. The test socket is positioned on the first board such that the pins of the test socket engage the electrical receptors and such that the exposed die of the die-down configured integrated circuit package is disposed over the first hole. The first board is coupled to a second board having electrical connectors extending from the bottom surface thereof.

Abstract: A process for producing placement information for layouts of circuit elements of networks that are initially represented by netlists such that datapaths can be advantageously placed into a regular array. In one preferred embodiment, the method includes steps of encoding datapath information in instance names of a netlist generated by a datapath compiler; using the encoded datapath information for defining partitioned areas that preserve datapaths; and generating circuit layouts from the netlist, which layouts contain floor plans of the datapaths.

Abstract: A synchronous sense amplifier stage includes means for shunting the signal input terminal of the sense amplifier stage to ground during a precharge interval for discharging charge on a read bit line connected to the input terminal of the synchronous sense amplifier during the precharge interval. Means are also provided for precharging predetermined internal nodes and the output terminal of the synchronous sense amplifier stage to predetermined voltages during the precharge interval.

Abstract: A pulse discharge circuit for pulse testing an integrated-circuit device under test (DUT) is provided which uses three separate switching relays S1, S2, and S3, which are operated in a predetermined sequence. For charging the capacitance of a pulse-forming transmission line, the relay contact of S1 is closed while the relay contacts of relays S2, S3 are both open. For discharging the charge on the transmission line to form a test pulse, the relay contact of S1 is first opened, and the relay contact of S2 is then closed while the relay contact of S3 is open. After each test pulse is generated and applied to a DUT, the condition of the DUT is determined by a leakage current measurement. The relay contact S2 is opened to isolate the pulse generator circuit and then the relay contact S3 is closed.

Abstract: A datapath circuit synthesizer converts an HDL circuit specification into a circuit netlist. The behavioral description of the specified circuit is divided into two distinct parts: datapath logic and control logic. The control logic is implemented in standard cells or gate arrays using a logic synthesizer. The datapath logic is optimally synthesized using a datapath synthesizer having a library of datapath elements, including both structural components and computational components, where some of the computational components are complex circuits having multiple, parallel outputs. Each computational component has associated therewith a set of one or more datapath expressions performed thereby. The received HDL circuit specification is converted into circuit data structures representing the circuit's datapath expressions and structural components. The datapath synthesizer locates all datapath elements in said library matching each such datapath expression and structural component.

Abstract: The present invention provides a CMOS integrated circuit in which core transistors are provided with punch-through pockets, while the input/output transistors are not provided with punch-through pockets. Punch-through protection for the input/output transistors by virtue of their larger dimensions. The pockets, like lightly doped drains, are formed after the gates are formed but before the formation of gate sidewalls. However, the input/output are masked during the punch-through implants, but are unmasked for at least one of the lightly doped drain implants. The absence of pockets on the input/output transistors enhances their ESD resistance, and thus the ESD resistance of the incorporating integrated circuit.