International Business Machines Corporation

Dale E Hoffman

Algirdas J Gruodis

Wiren Dale Becker

Howard Harold Smith

Allan Harvey Dansky

Peter J Camporese

Daniel E Skooglund

Kwok Fai Eng

Charles A Puntar

Bhupindra Singh

John G Torok

William P Kostenko

Karl Owen Casserly

Lawrence Joseph Grasso

Bohdan Demczar

Diane K Young

Jeffrey Herbert Fischer

Albert Y Chang

Kurt Paul Szabo

Michael L Combs

John E Dickol

Carroll E Morgan

A tool and technique are employed to distill and prioritize multiple organizational (sub-system) capabilities based on ranked customer requirements or desires. A translational matrix is employed to organize preferences of the sub-system with respect to the customer requirements or desires. Relative importance scores are input into the matrix to reflect prioritized input versus prioritized capabilities. An adjusted relative importance score of the sub-system is automatically calculated and a resultant re-prioritization of sub-system attributes is created for application to new designs, services, or processes.

Performing sub-system attribute modification

A method of evaluating decoupling capacitor placement for Very Large Scale Integrated Chips (VLSI) is disclosed. Included in the method is an analysis of the usage for each decoupling capacitor, the distance from the devices, and the locations of the devices and decoupling capacitors. Also addressed are the orientations and size of the components.

Method for evaluating decoupling capacitor placement for VLSI chips

A method, and apparatus for accomplishing the method, for controlling an operation of a test pin of a per-pin semiconductor device test system. The method includes the steps of, during a test cycle, generating a plurality of timing signals, providing a test pattern comprised of M-bits, and decoding the M-bits into one of 2.sup.M first multi-bit control words. In accordance with logical states of bits of the first control word, the method selects specified ones of the timing signals and generates a stimulus signal at a test pin in accordance with the selected specified ones of the timing signals. In accordance with an aspect of the invention, the step of providing provides test patterns at a rate of (x) test patterns per second, the step of generating generates test pin stimulus signals at a rate of (y) stimulus signals per second, and wherein (y)=n(x), where (n) is an integer greater than one.

Per pin circuit test system having N-bit pin interface providing speed

Apparatus and method for controlling an operation of a test pin of a per-pin semiconductor device test system [10]. The apparatus includes pattern storage memory [42] for storing and for outputting information related to a state of the test pin for individual ones of a plurality of consecutive test cycles, pattern processor [14] having an input coupled to the pattern storage memory for generating for each of the test cycles words comprised of M bits, and a test pin control memory [18] having an input coupled to the output of the pattern processor for decoding each of the words into 2.sup.M or less command words. Each of the decoded command words includes a plurality of control bits. Predetermined ones of the plurality of control bits are coupled to pin driver electronics [24,28] for specifying, for each of the test cycles, at least one characteristic of an electrical signal transmitted to the test pin. The test system also includes test pin signal receiving circuitry [26] for coupling to the test pin for receiving an electrical signal therefrom. Other predetermined ones of the control bits are coupled to the receiving circuitry for specifying, for each of the test cycles, at least one operating characteristic associated with the receiving circuitry.

Per-pin integrated circuit test system having n-bit interface

A driver circuit is disclosed for use in testing bi-directional transceiver semiconductor products using a minimum of time and number of product accessing pins. The driver includes a pair of controllable amplitude current sources whose output currents are selectably switched into or partially away from the commonly connected emitters of a current switch. The current switch is energized by a variable voltage source and produces the output test voltage.

Driver circuit for testing bi-directional transceiver semiconductor

A method of operating a delay circuit to impose a selected delay on an electronic signal the delay circuit comprising a plurality of delay stages and means for directing the electronic signal through selected ones of the delay stages, the method comprising the steps of: measuring the actual signal delay through each of the delay stages; and selecting, based on the signal delays obtained in the measuring step, the delay stages through which the electronic signal is directed.

Programmable delay line utilizing measured actual delays to provide a

A high speed counter circuit for counting electrical pulses includes a master/slave flip-flop at the input stage of the counter. An AND gate logically ANDs the pulses being counted with the master output to produce a first gating signal. A plurality of cascade coupled flip-flops each having a slave and an inverse slave output are provided. The clock input to each cascade coupled flip-flop is produced by the logical OR of the electrical pulses being counted, the first gating signal and the slave output of all preceding flip-flops of the counter. The counter output is provided by the inverse slave output of each flip-flop.

High speed digital counter

Disclosed is a method and circuit for reducing and maintaining constant overshoot in a high speed driver. The circuit includes a predriver circuit which is driven single endedly and a driver circuit which is differentially driven by the predriver outputs. The predriver and the driver are differential pairs, with commonly controlled individual transistor current sources. A diode has been added in series with each emitter of the differential pairs. Schottky diodes are preferable because of their low capacitance. The diodes increase the input switching voltage (the smallest input voltage swing that will cause the outputs to fully switch) of the differential pair because they must also be switched on and off. The increase results in an increase in effective transition time, which results in smaller overshoots because the circuit is being switched slower. The output amplitude of the driver is set by a voltage which controls the current source currents of the commonly controlled current sources. As the amplitude is decreased the input switching voltage decreases because the current through the devices decreases which results in smaller base-emitter and diode voltages. Due to the commonly controlled current sources, the predriver amplitude decreases as the driver amplitude decreases. The predriver is designed such that its variable output supplies the driver with the proper input switching voltage at any driver amplitude. This keeps the effective input transition time constant which results in constant output overshoot.

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Fishkill, NY, United States of America

Dale E Hoffman