Hewlett-packard Company

Vance R Harwood

Kamran Firooz

David T Crook

Ronald J Peiffer

Kevin W Keirn

Thomas R Fay

William A Groves

Sharon E LaTourrette

Jay Stepleton

Michael A Teska

Elton C Bingham

Matt Snook

Robert C Illick, Jr

John J Keller

Disclosed is a system for determining whether semiconductor components are present and properly connected to a printed circuit board. The semi-conductor material between two pins of an integrated circuit forms a lateral NPN transistor, having its base connected directly to the substrate connection pin of the component. A constant voltage source is applied to the lateral transistor collector pin of the component being tested, and allowed to stabilize. A current or voltage source is then connected to the emitter pin of the lateral transistor, typically an adjacent pin, and a current or voltage pulse is applied to this pin. The current on the collector pin is then monitored and if a corresponding current pulse is detected, the emitter and collector pins, as well as the substrate connection pin of the component, are properly connected to the printed circuit board.

Integrated circuit transfer test device system utilizing lateral

The present invention provides a circuit board tester for performing functional and in-circuit tests on one or more circuit boards. The circuit board tester includes a testhead for interfacing with one or more circuit boards and supplying the resources for the testing thereof. The testhead includes a plurality of modules with each module having a defined amount of resources and a processor for use in executing a test plan to test the circuit board. The circuit board tester further includes a high-speed link for coordinating the execution of a test plan by two or more modules when the resources of one module are insufficient to test a particular circuit board. Each module in the testhead can be selectively connected or disconnected from the high-speed link. Consequently, two or more modules can be connected to the high-speed link to test a first circuit board while another module, that is disconnected from the high-speed link, can concurrently test a second circuit board. The circuit board tester also, preferably, includes a controller that determines whether the resources of more than one module are required to test a particular circuit board and generates a test plan accordingly.

Modular/concurrent board tester

An improved digital testing device is presented which includes the capability to detect and avoid a pair of common sources of measurement error. One source of error occurs when measurements are made within a Setup time before a transition in the signal under test or during a Hold time after such a transition. This device includes the ability to detect when this occurs and to insert a relative delay between the measurements and transitions to eliminate such errors. The device also detects the existence of a 3-state condition of a point of the circuit under test during the period of a measurement and provides an output indication when such occurs.

Circuits and apparatus which enable elimination of setup time and hold

A method and apparatus are disclosed for reducing the likelihood of damage to digital logic devices under test or located in close electrical proximity to the device under test while attempting to locate faults in circuit assemblies using digital incircuit test techniques.

High throughput circuit tester and test technique avoiding overdriving

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Loveland, CO, United States of America

Vance R Harwood