Abstract:
An efficient automated test system and method are presented. In one embodiment, an automated test system is implemented in a routed event distribution architecture. In one exemplary implementation, an automated test system includes a plurality of test instruments, a switched event bus, and a test controller component. The plurality of test instruments perform testing. The switched event bus communicatively couples the plurality of instruments. The switched event bus comprises an event distribution switch that flexibly routes event information across event lines of the switched event bus. The test controller controls the testing and the switched event bus.

Description:
RELATED APPLICATIONS 
     This Application claims priority to and the benefit of U.S. Provisional Application No. 60/958,338 filed Jul. 3, 2007 entitled “A ROUTED EVENT TEST SYSTEM AND METHOD”, which is incorporated herein by this reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to the field of automated test equipment. 
     BACKGROUND OF THE INVENTION 
     Electronic and optical systems have made a significant contribution towards the advancement of modern society and are utilized in a number of applications to achieve advantageous results. Numerous electronic technologies such as digital computers, calculators, audio devices, video equipment, and telephone systems have facilitated increased productivity and reduced costs in analyzing and communicating data in most areas of business, science, education and entertainment. Electronic systems providing these advantageous results are often complex and are tested to ensure proper performance. However, traditional approaches to automated testing can be relatively time consuming and expensive. 
     Generally, the speed at which a testing is performed can have a significant impact on the cost of testing. As DUTs become more complex and sophisticated the testing also becomes more complex and have a variety of instruments that communicate with one another. Traditional testing systems typically have a bused event architecture that is rather limited. When one instrument gains control of the bus the other instruments are usually precluded from communicating with one another.  FIG. 4  is a block diagram of an exemplary conventional bused event architecture. This approach can impact the test production throughput while consuming limited bus resources. 
     SUMMARY 
     An efficient automated test system and method are presented. In one embodiment, an automated test system is implemented as a routed event distribution architecture. In one exemplary implementation, an automated test system includes a plurality of test instruments, a switched event bus, and a test controller component. The plurality of test instruments perform testing. The switched event bus communicatively couples the plurality of instruments. The switched event bus comprises an event distribution switch that flexibly routes event information across event lines of the switched event bus. The test controller controls the testing and the switched event bus. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are incorporated in and form a part of this specification, illustrate embodiments of the invention by way of example and not by way of limitation. The drawings referred to in this specification should be understood as not being drawn to scale except if specifically noted. 
         FIG. 1  is a block diagram of an exemplary automated test system in accordance with one embodiment of the present invention. 
         FIG. 2A  is a block diagram of an exemplary automated test system in accordance with one embodiment of the present invention. 
         FIG. 2B  is a block diagram of an exemplary automated test system in accordance with one embodiment of the present invention. 
         FIG. 3  is a flow chart of an exemplary automated testing methods in accordance with one embodiment of the present invention. 
         FIG. 4  is a block diagram of an exemplary conventional bused event architecture. 
     
    
    
     DETAILED DESCRIPTION 
     Reference will now be made in detail to the preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. While the invention will be described in conjunction with the preferred embodiments, it will be understood that they are not intended to limit the invention to these embodiments. On the contrary, the invention is intended to cover alternatives, modifications and equivalents, which may be included within the spirit and scope of the invention as defined by the appended claims. Furthermore, in the following detailed description of the present invention, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be obvious to one of ordinary skill in the art that the present invention may be practiced without these specific details. In other instances, well known methods, procedures, components, and circuits have not been described in detail as not to unnecessarily obscure aspects of the present invention. 
     Some portions of the detailed descriptions which follow are presented in terms of procedures, logic blocks, processing, and other symbolic representations of operations on data bits within a computer memory. These descriptions and representations are the means generally used by those skilled in data processing arts to effectively convey the substance of their work to others skilled in the art. A procedure, logic block, process, etc., is here, and generally, conceived to be a self-consistent sequence of steps or instructions leading to a desired result. The steps include physical manipulations of physical quantities. Usually, though not necessarily, these quantities take the form of electrical, magnetic, optical, or quantum signals capable of being stored, transferred, combined, compared, and otherwise manipulated in a computer system. It has proven convenient at times, principally for reasons of common usage, to refer to these signals as bits, values, elements, symbols, characters, terms, numbers, or the like. 
     It should be borne in mind, however, that all of these and similar terms are associated with the appropriate physical quantities and are merely convenient labels applied to these quantities. Unless specifically stated otherwise as apparent from the following discussions, it is appreciated that throughout the present application, discussions utilizing terms such as “processing”, “computing”, “calculating” “determining”, “displaying” or the like, refer to the action and processes of a computer system, or similar processing device (e.g., an electrical, optical, or quantum, computing device) that manipulates and transforms data represented as physical (e.g., electronic) quantities. The terms refer to actions and processes of the processing devices that manipulate or transform physical quantities within a computer system&#39;s component (e.g., registers, memories, other such information storage, transmission or display devices, etc.) into other data similarly represented as physical quantities within other components. 
     Present invention automated test equipment (ATE) systems and methods are described. In one embodiment, signal processing is performed in real time. In addition, testing configuration flexibility can be facilitated including in the field (e.g., at a customer facility, remote location, etc.) configuration capabilities. In one exemplary implementation, parallel testing of devices is also supported. These and other features are set forth in more detail in the following description. 
       FIG. 1  is a block diagram of exemplary automated testing environment  100  in accordance with one embodiment of the present invention. Automated testing environment  100  includes device under test (DUT)  110  and  115 , automated test system  120  which includes automated test instruments  121  and  122 , and control station  123 . Device under test  110  and  115  are selectively coupled to automated test instruments  121  and  122  which in turn are selectively coupled to control station  123 . 
     The components of automated testing environment  100  cooperatively operate to provide efficient testing of device under test  110  and  115 . Device under test  110  and device under test  115  are the devices being tested. In one embodiment, device under test  110  and device under test  115  can be tested in parallel. Automated test instrument system  120  coordinates and processes information received from device under test  110  and device under test  115 . System controller  130  controls the testing of devices  110  and  115  and receives the processed information from automated test instrument component  120 . 
     It is appreciated that automated test instrument component  120  facilitates efficient and effective testing. In one embodiment, automated test instrument component  120  performs real time digital signal processing. In one embodiment, real time processing includes the time it takes the automated test instrument component to perform the digital signal processing in hardware of the automated test instrument component  120 . 
       FIG. 2A  is a block diagram of exemplary automated test system  200 A in accordance with one embodiment of the present invention. Automated test system  200 A includes test instruments  211 ,  212 ,  213 ,  221 ,  222 , and  223 , event distribution switch (SW)  231 , event distribution switch (SW)  251  and event distribution switch (SW)  241 . The test instruments  211 ,  212 ,  213 ,  221 ,  222 , and  223 , and event distribution switches  231 ,  251  and  241  are communicatively coupled in a hierarchical configuration. The test instruments  211 ,  212 ,  213 ,  221 ,  222 , and  223  are in a low hierarchical level, event distribution switches  231  and  251  are in a middle hierarchical level and event distribution switch  241  is in a high level hierarchical level. 
     The components of automated test system  200  cooperatively operate to test devices. Instruments  211 ,  212 ,  213 ,  221 ,  222 , and  223  direct testing operations and generate test events. Event distribution lines  270 ,  280  and  290  communicate test event information between components of automated test controller  200 . The test events are communicated to other components within automated test controller  200  by being routed through event distribution lines by event distribution switches  231 ,  241  and  251 . In one embodiment, automated test system  200  includes a user interface for interfacing with a user. 
     In one embodiment, the event distribution switches receive the event indication information and determine routing instructions for the event information. In one exemplary implementation, the event distribution switches are software controlled. The software instructions direct which event lines are going to be used for the different event functions (e.g., qualifiers, failures, etc.). The software configures the switches to route the event information accordingly and then the test controller runs the events for the rest of the test. 
     For example, if instrument  211  defines an event line as a trigger and instrument  211  wants to send a trigger to  213 ,  221  and  222  the event distribution switches are configured to route the triggers accordingly. For example, one of the event lines is used as a trigger line coming out of instrument  211  and a determination is made as to which of the event lines going to the other instruments will be utilized as a trigger event line. Once the decision is made, it then determines which resources are available in the switch and the best way to route the event in from one end and distribute it out to the others that are going to receive the event information. For example, distribution switch  231  routes the trigger to instrument  213  and forwards the trigger up the hierarchy to distribution switch  241  which routes the trigger down the hierarchy to distribution switch  251  which in turn routes the trigger to instruments  221  and  222 . 
     It is appreciated that the routing can be established in accordance with a variety of objectives. For example, the routing can be done in a way that is the shortest or fastest. In one exemplary implementation the routing is configured in a manner that facilitates synchronization maintenance. For example, switch routing is selected in a manner so that the instruments have the same timing. 
       FIG. 2B  is a block diagram of exemplary automated test system  200 B in accordance with one embodiment of the present invention. Automated test system  200 B is an exemplary implementation of automated test system  200 A in which the distribution switches are located in hierarchical components. Automated test system  200  includes test instruments  211 ,  212 ,  213 ,  221 ,  222 , and  223 , backplane  230 , backplane switch (AKA) test head motherboard (THMB)  240  and backplane  250 . Backplane  230  includes event distribution switch (SW)  231  and backplane  250  includes event distribution switch  251 . Test head mother board  240  includes event distribution switch  241 . The test head motherboard  240  is a higher hierarchical level than the backplane  230  and backplane  250 . In one exemplary implementation, the switch  231  of backplane  230  routes signals to and from test instruments  211 ,  212  and  213 , and switch  251  of backplane  250  routes signals to and from test instruments  221 ,  222  and  223  while the distribution switch  241  of test head motherboard (THMB)  240  routes information between backplane  231  and backplane  251 . 
       FIG. 3  is a flow chart of automated testing method  300  in accordance with one embodiment of the present invention. 
     In block  310  test event information is received. It is appreciated that a variety of test event information can be used. For example, test event information can include trigger information, failure information, qualifier information, etc. 
     At block  320  routing for the test event information is determined. In one embodiment the routing includes analyzing characteristics of a test event. An event characteristic is assigned to an event line in accordance with the analysis. For example, if an analysis indicates an instrument is attempting to communicate a failure event to another instrument, event lines between the instruments are designated as failure event lines for the purposes of communicating the failure event. In one embodiment routing is selected to facilitate synchronization maintenance. 
     In block  330 , routing of the test event information is executed. In one embodiment routing is included in the backplane of a test bucket. In one exemplary implementation a backplane is included in a test bucket and a test head motherboard interconnects a plurality of backplanes (e.g., multiple buckets). Routing is included in a test head mother board for communicatively coupling a plurality of backplanes in different test buckets. 
     In one embodiment, an event test switch can combine event information from a variety of instruments for routing to other instruments. In one exemplary implementation, an event test switch can be utilized to route information to a test controller. 
     Thus, the present invention facilitates efficient automated testing of devices. The present approach facilitates re-use of existing test programs to test different DUTs in the same package or test different DUTs in different packages in parallel. The present approach also allows re-use of the same test program in wafer sort and final test. Additionally, this capability allows the diagnosing of different instrument types in parallel. 
     The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, to thereby enable others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the Claims appended hereto and their equivalents.