Error detection/correction and fault detection/recovery – Pulse or data error handling – Digital logic testing
Reexamination Certificate
1998-03-30
2001-04-10
Decady, Albert (Department: 2784)
Error detection/correction and fault detection/recovery
Pulse or data error handling
Digital logic testing
C714S733000, C714S030000, C702S121000
Reexamination Certificate
active
06216243
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention generally relates to the discovering of failures in complex systems for data processing purposes.
Discovering of failures in complex systems, i.e. systems with a plurality of subsystems, generally exhibits difficulties since there might be a plurality of difficult failures in the various subsystems, and the failures might also reveal in different forms. Failures which can obviously be seen, such as when a system is completely inoperable, can easily be detected by the user of the system. However, in case that internal parameters within the system or the subsystems change and thus influence the entire system, this might not be detected from outside, e.g., by the user. These failures might only turn out by their effects and can solely be detected by trained users, special instructed persons, or by sp cific inspection routines.
Some failures occurring in one subsystem only have an impact on the subsystem itself e.g. in a way that only the subsystem might become inoperable. However, other failures occurring in one subsystem might also influence other s bsystems and thus the entire system.
Examples for systems which are in particular sensitive for failures are automated test equipment (ATE) systems, such as IC testers, or sorting and packaging machines with optical recognition of products, or the like. Defects or failures in one subsystem can influence the entire ATE system in a way that the testing results can be erroneous and might not represent the actual state of a device under test (DUT). This can lead to a reduced yield of the DUTs to be tested and components which are well functioning might be selected as defective, and vice versa.
Failures in complex systems are usually detected in the art by specific diagnosis routines monitoring the functional ability (functionability) of the system. The diagnsis routines are normally started in defined service or maintenance intervals, or before use of the system. The execution of such a diagnosis routine is to be started by the user or might be automatically and periodically started by the system. The effective using time of the system is reduced by the time required for executing the diagnosis routines. In case the system is used for production or testing purposes, the time required for executing the diagnosis routines might increase the product costs of the devices to be produced or tested by the system. Furthermore, failures occurring during the operation of the system might not be recognized and can lead to a series of faulty products.
SUMMARY OF THE INVENTION
It is an object of the present invention to improve the detection of failures occurring in complex systems.
According to the invention, a complex system is monitored substantially permanently at p edefined monitoring points by means of one or more diagnosis modules respectively within one or more subsystems of the system. The diagnosis modules provide their measuring results to an evaluation unit for evaluating define d parameters and properties of the subsystem and thus of the system.
The term ‘substantially permanently monitoring’ as used herein means that the monitoring is exe uted substantially in parallel to and independent of other running programs events, tasks, or the like within the system. However, the monitoring and evaluating according to the invention might also be run with a lower or higher priority that other running programs or tasks within the system in order to improve possible runtime constraints within the system. In case that the entire system or respective subsystems are operated in a standby mode, the monitoring is preferably carried on, whereas in case that the entire system or respective subsystems are switched of or in a disconnected mode, the monitoring within the entire system or the respective subsystems is preferably not maintained and also switched of or disconnected. For that reason, the monitoring is preferably driven by an own separate power supply.
A system according to the invention comprises a plurality of subsystems, whereby at least on of the plurality of subsystems comprises one or more monitoring points reevant and representative for certain parameters of the respective subsystem and each one of the one or more monitoring points is connected with a respective diagnosis module for substantially permanently monitoring the respe ve monitoring point An evaluation unit is connected with each respective diagnosis module for receiving information therefrom about each respective monitoring point and for evaluating the received information in order to draw back onto parameters and properties within the system.
A method according to the invention for discovering failures in the system according to the invention comprises steps of substantially permanently monitoring the respective monitoring point, receiving information from each respective diagnosis module about each respective monitoring point, and evaluating the received information in order to draw back onto parameters and properties within the system.
The invention is preferably used in an automated test equipment system.
The predefined monitoring points have to be selected as relevant and representative for the functionality of a respective subsystem and thus of the functionality of the entire system. The diagnosis modules are preferably coupled by a communication channel connecting the respective diagnosis modules with the evaluation unit.
The evaluation unit is preferably controlled by a software program which is executed substantially permanently and in parallel to other running programs or tasks within the system.
The invention allows to permanently monitor and observe parameters of the system without unduly influencing the usage of the system. In case of a failure occurring or when observed parameters of the system tend to drift, the user of the system can be informed by the evaluation unit during the normal operation of the system.
The invention further allows to postpone or suspend an intended inspection cycle of the system in case that no drifting of parameters or that no failures are observed by the evaluation unit. This leads to increased inspection intervals of the system and thus to an increased effective using time of the system and decreased expenditure for maintaining and inspecting the system.
The reliability of the system and of working results from the systems can thus be significantly improved.
Particularly in ATE systems, the invention allows to reliably carry out the respective testing. The monitoring points have to be carefully selected in order to draw conclusions about the tests to be performed.
REFERENCES:
patent: 4807161 (1989-02-01), Comfort et al.
patent: 5081598 (1992-01-01), Bellows et al.
patent: 5127009 (1992-06-01), Swanson
patent: 5202639 (1993-04-01), McKeon et al.
patent: 5544308 (1996-08-01), Giordano et al.
patent: 5566092 (1996-10-01), Wang et al.
patent: 5663656 (1997-09-01), Wilson et al.
patent: 5734567 (1998-03-01), Griffiths et al.
Chase Shelly A
De'cady Albert
Hewlett-Packard
LandOfFree
Permanent failure monitoring in complex systems does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Permanent failure monitoring in complex systems, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Permanent failure monitoring in complex systems will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2492581