Washington, DC -- October 20, 1998 -- Teradyne, Inc. (NYSE:TER) announced the introduction of the BusScan stuck bus-diagnosis subsystem, an option for the popular Z1800-Series manufacturing test system, for the detection and diagnosis of bus-related faults on printed circuit assemblies. The announcement was made at the International Test Conference (ITC) held October 18-23 in Washington, DC.

Employed at "bed-of-nails" in-circuit test during the board assembly and test process, BusScan utilizes a newly developed current sensing technique that detects and diagnoses bus-related faults on boards where tri-state inputs and outputs of multiple semiconductor devices are connected together. Using a patent-applied-for current line pulse sensing method, normal in-circuit test vectors pulse selected bus lines while the BusScan circuitry measures dynamic current response. The ability to diagnose a fault down to the specific failing "stuck"pin and determine its condition—open pin or high impedance short—significantly improves the diagnostic accuracy for this fault class.

According to Craig Pynn, Assembly Test Division, Marketing Manager, "This is the first highly repeatable easily programmed bus fault test available to board manufacturers on any in-circuit tester. BusScan is also simpler to program than existing methods used by both Teradyne and competitive in-circuit testers and provides redundant, accurate, and reliable test data that manufacturers require. Teradyne is pleased to provide Z1800 customers with this innovative approach to efficient bus test as a cost-effective add-on."

The BusScan configuration simplifies setup via a board mounted in the "bed-of-nails" fixture together with a random wiring design, thereby eliminating tester-based switching and addressing requirements. A single tester digital measurement channel is used to check the state of all buses, resulting in very high throughput speeds. From a software point of view, BusScan is an automatic test and diagnostic tool that may be added to the Z1800-Series operating system. Worksheet variables include test type selection page, automatic test result analysis, and diagnostic printout format.

BusScan specifications include: vector clock rate 500Khz to 1Mhz, resolution 20 mA, dynamic load 1.7 ohm. Each BusScan board accommodates up to 32 lines; up to five BusScan boards (160 channels) can be handled by a single Z1800 measurement channel. The BusScan stuck bus diagnosis subsystem may be retrofitted to any Z1800-Series model running F.2 (or later) operating system software.

Pricing for BusScan when purchased as an option on new systems starts at around $4500. Retrofit prices are slightly higher; site licenses are available. BusScan is currently available for shipment.

Teradyne is the world's largest manufacturer of automatic test equipment ("ATE") for the electronics industry. Products include systems to test semiconductors, circuit boards and modules, telephone lines, computerized telephone systems, and software. The Company is also a leading manufacturer of backplanes and associated high-density connectors used in electronic systems. Teradyne supports these products through an extensive service and application engineering network, with technical centers located throughout the United States, Europe, and Asia's Pacific Rim.

The Assembly Test Division, located in Boston and Walnut Creek, California, serves circuit-board test customers with comprehensive capabilities in test and inspection. These test instruments and systems are used in commercial environments and in military/aerospace applications where reliability, time-to-market, and in-line process test are key to success. Headquartered in Boston, Massachusetts, Teradyne reported sales of approximately $1.3 billion in 1997 and had 6300 employees worldwide.

BusScan is a trademark of Teradyne, Inc.

Teradyne introduces BusScan for the Z1800-Series. A new test method to detect and diagnose bus related faults. Note: Photographic prints, transparencies, or an electronic file of this image is available from Karen Kilcoyne 617.422.3808.