Abstract: Precise timing control across multiple standardized chassis such as PXI is obtained by providing several control signals over PXI_LOCAL within each chassis, and by providing these control signals to other chassis. A Least Common Multiple (LCM) signal enables all clocks to have coincident clock edges occurring at every LCM edge. A start sequence allows all PXI expansion cards in the test system to start at the same time. A MATCH line enables pincard modules to check for expected DUT outputs and either continue execution of their local test programs or loop back and repeat a section of the local test program in accordance with the result of the DUT output check. An End Of Test (EOT) line enables any one pincard module to abruptly end the local test programs running in all other pincard modules if an error is detected by the local test program in the pincard module.

Abstract: A roof ridge vent has a pair of opposed, spaced-apart, elongate strips of ventilation material providing ventilation passageways transversely therethrough and forms opposed longitudinally-extending sides of the vent. The elongate ventilation strips are interconnected by a plurality of supports extending transverse relative to the elongate ventilation strips. Each adjacent pair of supports defines an opening therebetween such that an underlying roof surface is visible to an installer through the openings. A vent assembly and method of installation are provided.

Abstract: Precise timing control within a standardized chassis such as PXI is obtained by providing several control signals over PXI_LOCAL. A Least Common Multiple (LCM) signal enables all clocks to have coincident clock edges occurring at every LCM edge. A start sequence allows all PXI expansion cards in the test system to start at the same time. A MATCH line enables pincard modules to check for expected DUT outputs and either continue execution of their local test programs or loop back and repeat a section of the local test program in accordance with the result of the DUT output check. An End Of Test (EOT) line enables any one pincard module to abruptly end the local test programs running in all other pincard modules if an error is detected by the local test program in the pincard module.

Abstract: Precise timing control within a standardized chassis such as PXI is obtained by providing several control signals over PXI_LOCAL. A Least Common Multiple (LCM) signal enables all clocks to have coincident clock edges occurring at every LCM edge. A start sequence allows all PXI expansion cards in the test system to start at the same time. A MATCH line enables pincard modules to check for expected DUT outputs and either continue execution of their local test programs or loop back and repeat a section of the local test program in accordance with the result of the DUT output check. An End Of Test (EOT) line enables any one pincard module to abruptly end the local test programs running in all other pincard modules if an error is detected by the local test program in the pincard module.

Abstract: An apparatus and method for computing event timing for high speed event based test system. The event processing apparatus includes an event memory for storing event data of each event where the event data includes timing data for each event which is formed with an integer multiple of a clock period and a fraction of the clock period, an event summing logic for accumulating the timing data and producing the accumulated timing data in a parallel form, and an event generator for generating events specified by the event data based on the accumulated timing data received in the parallel form from the event summing logic. The events in the event data are specified as groups of events where each group of event is configured by one base event and at least one companion event.

Abstract: Method for radiographic imaging, in particular for measuring the bone mineral density of an osseous body, this method involving an operation which consists in determining the value of a composite index using, on the one hand, digitized radiological data, and, on the other hand, a three-dimensional generic model of said osseous body.

Abstract: An event based test system for testing an IC device under test (DUT) designed under an automatic electronic design (EDA) environment. The event based test system includes an event memory for storing event data derived directly from simulation of design data for an intended IC in the EDA environment where the event data to denote each event is formed with time index indicating a time length from a predetermined point and an event type indicating a type of change at an event, an event generation unit for generating test vectors based on the event data where waveform of each vector is determined by the event type and a timing of the waveform is determined by accumulating the time index of previous events, and means for supplying test vectors to the DUT and evaluating response outputs of the DUT at predetermined timings.

Abstract: An event pipeline and vernier summing apparatus for high speed event based test system processes the event data to generate drive events and strobe events with various timings at high speed to evaluate a semiconductor device under test. The event pipeline and vernier summing apparatus is configured by an event count delay logic, a vernier data decompression logic, an event vernier summation logic, an event scaling logic, and a window strobe logic. The event pipeline and summing method and apparatus of the present invention is designed to perform high speed event timing processing with use of a pipeline structure. The window strobe logic provides a function for detecting a window strobe request and generating a window strobe enable.

Abstract: A time shift circuit for changing a delay timing of a portion of a test pattern for testing a semiconductor device. The time shift circuit includes a multiplexer for selectively producing delay value data indicating a value of time shift in response to a shift command signal, a vernier delay unit for producing timing vernier data based on the delay value data selected by the multiplexer, and a timing generator for generating a timing edge for the specific portion of the test pattern based on the timing vernier data from the vernier delay unit. The shift command signal sets either a normal mode where predetermined delay value data is selected by the multiplexer or a time shift mode where delay value data for shifting the timing edge in real time is selected by the multiplexer.

Abstract: An ATE calibration method and system that does not require external test equipment to calibrate individual functional pins and provides balanced timing skews among the functional pins and pincards is disclosed. A functional pin in the test system is selected as a reference or “golden” pin and another is selected as a precision measurement unit (PMU). External test equipment and the reference PMU are used to measure the AC and DC characteristics of the reference pin, and any deviation represents a measurement error in the reference PMU. All functional pins in the test system can be measured against the reference pin using the reference PMU, taking into account the measurement error, without the need for external test equipment. To ensure that skews are balanced among all pins, the location of the reference pin is selected to be as close as possible to the midpoint of the functional pin range.

Abstract: An ATE calibration method and system that does not require external test equipment to calibrate individual functional pins and provides balanced timing skews among the functional pins and pincards is disclosed. A functional pin in the test system is selected as a reference or “golden” pin and another is selected as a precision measurement unit (PMU). External test equipment and the reference PMU are used to measure the AC and DC characteristics of the reference pin, and any deviation represents a measurement error in the reference PMU. All functional pins in the test system can be measured against the reference pin using the reference PMU, taking into account the measurement error, without the need for external test equipment. To ensure that skews are balanced among all pins, the location of the reference pin is selected to be as close as possible to the midpoint of the functional pin range.

Abstract: An apparatus for supporting and manipulating a testhead for testing semiconductor devices includes a supporting frame, plates adapted to be mounted on opposite sides of the testhead and controllable shafts that connect the supporting frame to the plates. Each plate has an opening in which a flanged bearing is fitted. The testhead is mounted by moving the respective shafts through the flanged bearings within the openings of plates. In this manner, the shafts support the testhead on two fixed pivots. The shafts also provide a fixed axis of rotation about which the testhead can be rotated. The testhead can be locked in a particular position about the fixed rotation axis by a locking pin inserted into one of a plurality of locking holes surrounding the plate opening. A lever arm connected to the locking pin is utilized to change the radial position of the testhead. The testhead is dismounted by unlocking the locking pin and moving the shafts from the flanged bearings.

Abstract: The present invention is directed to a locking apparatus and loadboard assembly of a semiconductor testing device apparatus. The loadboard assembly includes a printed circuit board containing a device under test and an interface board secured to the bottom of the printed circuit board. The interface board has two members with a space between them. Spacers connect the members to form apertures for contact pins on a test head. The loadboard assembly is placed on top of a locking apparatus which is mounted on the top surface of the test head. The placement of the loadboard on the locking apparatus is done according to two pins of different cross-sections that extend through two holes in the interface board and printed circuit board of the loadboard assembly. When the loadboard assembly is placed on the locking mechanism, rollers mounted on the interface board are received in cam slots of a cam member of the locking apparatus. These rollers follow the cam slots as the cam member is moved.

Abstract: An event pipeline and vernier summing apparatus for high speed event based test system processes the event data to generate drive events and strobe events with various timings at high speed to evaluate a semiconductor device under test. The event pipeline and vernier summing apparatus is configured by an event count delay logic, a vernier data decompression logic, an event vernier summation logic, an event scaling logic, and a window strobe logic. The event pipeline and summing method and apparatus of the present invention is designed to perform high speed event timing processing with use of a pipeline structure. The window strobe logic provides a unique means for detecting a window strobe request and generating a window strobe enable.

Abstract: The present invention is directed to a locking apparatus and loadboard assembly of a semiconductor testing device apparatus. The loadboard assembly includes a printed circuit board containing a device under test and an interface board secured to the bottom of the printed circuit board. The interface board has two members with a space between them. Spacers connect the members to form apertures for contact pins on a test head. The loadboard assembly is placed on top of a locking apparatus which is mounted on the top surface of the test head. The placement of the loadboard on the locking apparatus is done according to two pins of different cross-sections that extend through two holes in the interface board and printed circuit board of the loadboard assembly. When the loadboard assembly is placed on the locking mechanism, rollers mounted on the interface board are received in cam slots of a cam member of the locking apparatus. These rollers follow the cam slots as the cam member is moved.

Abstract: The present invention is directed to a test head Hifix of a semiconductor device testing apparatus that does not require disassembly for maintenance or repair of the semiconductor device testing apparatus. In one embodiment, the test head Hifix of a semiconductor device testing apparatus includes a plate that resides as the top surface of a test head and on which the assembly, loadboard, socket and DUT are mounted. The plate is attached to the test head in an arrangement that allows the plate along with the assembly, loadboard, socket and DUT to be easily moved without completely disassembling the plate, assembly and loadboard from the test head. In one embodiment, the plate is attached or coupled to the test head by hinges.

Abstract: An apparatus and method in an event based test system for testing an electronics device under test (DUT). The apparatus includes an event memory for storing timing data and event type data of each event wherein the timing data of a current event is expressed by a delay time from an event immediately prior thereto with use of a specified number of data bits, and an additional delay time inserted in the timing data of a specified event in such a way to establish a total delay time of the current event which is longer than that can be expressed by the specified number of data bits in the event memory. The additional delay time is inserted by replicating the timing data and the event type data of the event immediately prior to the specified event.

Abstract: An apparatus and method for computing event timing for high speed event based test system. The event processing apparatus includes an event memory for storing event data of each event where the event data includes timing data for each event which is formed with an integer multiple of a clock period and a fraction of the clock period, an event summing logic for accumulating the timing data and producing the accumulated timing data in a parallel form, and an event generator for generating events specified by the event data based on the accumulated timing data received in the parallel form from the event summing logic.

Abstract: An event based test system for testing an IC device under test (DUT) designed under an automatic electronic design (EDA) environment. The event based test system includes an event memory for storing event data derived directly from simulation of design data for an intended IC in the EDA environment wherein the event data to denote each event is formed with time index indicating a time length from a predetermined point and an event type indicating a type of change at an event, an event generation unit for generating test vectors based on the event data from the event memory where waveform of each vector is determined by the event type and a timing of the waveform is determined by accumulating the time index of previous events, and means for supplying test vectors to the DUT and evaluating response outputs of the DUT at predetermined timings.

Abstract: An event based test system can generate scan vectors for testing a semiconductor device of scan design without requiring a large amount of scan memory. The test system includes an event memory for storing timing data and event type data of each event where the timing data is expressed by N data bits for defining one test vector, an event generator for generating an event with use of the timing data and the event type data, and a mode change circuit provided between the event memory and the event generator for changing signal paths between a normal mode for generating the test vectors and a scan mode for generating the scan vectors. In the test system, each bit of the N data bits in the event memory defines 2N scan vectors which are provided to the event generator in a series fashion, thereby producing the 2N scan vectors at each access of the event memory.