Teradyne

About: Teradyne is a company organization based out in Boston, Massachusetts, United States. It is known for research contribution in the topics: Signal & Automatic test equipment. The organization has 828 authors who have published 999 publications receiving 15695 citations.

Identifying potentially-defective picture elements in an active-matrix display panel

Abstract: An example process includes: powering, via a power supply, an active-matrix display panel comprised of picture elements; and identifying, based on an output of the power supply, one or more picture elements in the active-matrix display panel that are potentially defective. The example process may also include identifying, among one or more of the picture elements that are potentially-defective, one or more picture elements that actually are defective.

What to do when your automated test equipment and Unit Under Test are out of reach

Abstract: Cabling from the Unit Under Test (UUT) to the Test System has become an increasingly difficult challenge to overcome. There are a few distinct challenges. The distance between the UUTs and the Test System has become a major challenge with today's high speed busses. Current UUTs and Test Systems have trouble driving long cable lengths of 10 meters or more due to signal integrity reasons, latency, and the skew across high speed busses which can run as fast as 5Gb/s. Also, multipoint busses such as PCI do not have support for external cabling solutions which makes testing difficult. Furthermore, limited space in the General Purpose Interface (GPI) prevents the tester from cabling out all necessary signals. This paper will explore a solution to these problems, which is to bring a piece of the Test System close to the UUT, instead of bringing the UUT close to the Test System. In most Test Systems, there exists a master chassis with instrumentation. The key to solving this problem is to create a small form factor chassis that can be placed close to the UUT, which can be thought of as a Remote Test Head. The Remote Test Head is an extension of the Master Chassis allowing the same instrumentation and software to be used as in the local system; therefore saving the System Designer and TPS Developer from having to design new instrumentation or writing new tests. The connection between the Test System and the Remote Test Head is optical thus alleviating problems with signal integrity. The connection allows the Remote Test Head and the Test System to be more than 10m apart while still maintaining a throughput of 5Gb/s even when going through a GPI.

Implementing boundary scan test strategies

Abstract: Board-level boundary scan testing, focusing largely on the boundary scan EXTEST mode for structural testing of interconnects between boundary scan devices on a board and testing of conventional, nonscan components which cannot be accessed using traditional in-circuit or cluster test techniques, is dealt with. Strategies and test-nail placement for implementing various types of boundary scan testing are detailed. The strategies discussed are virtual interconnect, virtual in circuit, standard cluster testing, and virtual cluster testing. It is shown that, where restricted physical access hampers in-circuit or cluster testing, virtual access provided by boundary scan device leads may offer the means of assuring a comprehensive test. When both physical and virtual access is needed, this requirement must be taken into account during board design and factored into board layout to ensure successful implementation of the test. >

Calibrating single ended channels for obtaining differential performance level

Abstract: In an automatic test system, a technique for deskewing driver circuits allows differential signals to cross at or near their 50%-points. First and second driver circuits, respectively coupled to first and second inputs of a measurement circuit, each generate an edge that propagates toward the DUT and reflects back when it reaches an unmatched load at the DUT. The test system measures the time interval between the edge and its reflection, for each input of the measurement circuit. Variable delay circuits are disposed in series with each of the driver circuits. In response to the measured time intervals, the test system adjusts the variable delay circuits, to ensure that signals from the first and second driver circuits arrive at the DUT at substantially the same time.

Carrier-based test system

Abstract: An example test system includes a test carrier to receive a device to test. The test carrier includes test components to perform at least a structural test on the device. The example test system also includes a slot to receive the test carrier. The slot includes an interface to which the test carrier connects to enable the test carrier to communicate with a system that is part of the test system or external to the test system.