Testing Of Electronic Systems Research Articles

SU-GG-I-154: Automated US QC with Phantoms - A Comparison with Electronic Transducer Testing

Purpose: To compare the ability of automated quality control software to detect flaws in ultrasound transducers as compared with an electronic transducertestingsystem.Method and Materials: A standard tissue‐mimicking quality control phantom was used to acquire images with an ultrasoundsystem that has defective transducer elements. A program written specifically to evaluate image quality parameters was used to evaluate the resultant images. The automated QC program was compared against a commercially available system that evaluates the transducer while it is detached from the rest of the ultrasoundscanner. Variables evaluated include image uniformity, sensitivity (depth of penetration) and spatial/contrast resolution. Results: The automated QC software was able to detect the transducer flaws that existed on the given transducer. This was also detected by the electronic transducer test system. The results from the latter depict transducer elements that are not operating properly, either due to delamination of the piezoelectric element from the acoustic coupling layer, contact failure, or grounding of the line in the cable. The automatic QC program is not able to detect this level of detail, however, the results from image analysis are more relevant to overall system performance. Conclusion: The ability of an automated QC program to detect transducer flaws has been evaluated. The automated QC program is not able to provide details of the transducer failure to direct repairs, however, it is able to detect subtle changes in transducer/ultrasound scanner performance in total. Therefore, the use of such a system will provide the physicist/engineer with objective imaging performance measurements. Comparisons of cost and ease of use will be included in the summary of this work and the reliability of each system to improve the quality of ultrasound studies will be discussed.

Structural Modal Analysis for Detecting Open Solder Bumps on Flip Chips

Although flip chips have received wide acceptance as an integrated circuit package, significant manufacturing problems exist with the integrity of the connection between the package and the printed circuit board (PCB). Conventional X-ray, ultrasonic and electronic testing systems have been used to assess the integrity of this connection, however, none of these have proven suitable for detecting open solder bumps between the chip and the board. The inability to detect open solder bumps with traditional methods merits the investigation of new, nondestructive methods for detecting defects in a manufacturing environment. This work assesses the feasibility of monitoring the vibration characteristics of flip chips to detect open solder joints. Test vehicles with open solder joints were created, and a nondestructive laser ultrasonic system was used to measure the free vibration response of the chips attached to the printed circuit board. The algorithm of mode isolation (AMI) was applied to the vibration response data in order to extract the modal parameters of the chip. The statistical differences between the modal parameters of sets of damaged and undamaged chips were assessed, revealing the ability of the method to determine the location and severity of these defects in the presence of experimental scatter and manufacturing variation. The parameters of the first mode of vibration, especially its mode shape, were found to be much more sensitive to damage than those of a higher frequency mode.

Quantification of creep strain in small lead-free solder joints with the in situ micro electronic-resistance measurement

Single shear lap creep specimens with a 1 mm 2 cross sectional area (similar in size to small lead-free solder joints used in electronic packaging and jointing) between thin copper strips were developed and fabricated using lead-free solder (Sn–3.5Ag) to quantify their creep strain with in situ micro electronic-resistance measurement. Where the solder joints’ micro electronic-resistance is in situ measured by an electronic testing system (tailor-made for the micro electronic-resistance and stress measurement) and recorded by a PC via serial port, then all data of micro electronic-resistance and elapsing time are formed in curves. They are used to describe the solder joints’ micro electronic-resistance and electronic-resistance strain varied with time. Most of curves can reveal the continual development of damage and fracture mechanisms which are consistent with observations generated by literatures. The quantitative relationship between electronic-resistance strain and mechanical-creep strain was proved theoretically using a mathematic model. These mean that the in situ micro electronic-resistance measurement can be used as an alternative quantification of creep strain in small lead-free solder joints. Thus, provide an alternative and simplified evaluation method about the reliability of a solder joint.

Biased mixed flowing gas testing for world class reliability

The reliability of complex installed systems is a function of many variables, including those inherent in the operating environment. Recent changes in world market conditions and pressure for environmentally-friendly products require the rapid availability of reliability information for new products installed in stressful environments. The thorough evaluation of design reliability requires that accelerated testing incorporate as many real causes of failure as possible. Biased mixed flowing gas (BMFG) tests cover the most significant categories of stress variables inherent in real world operating conditions and are capable of simulating mass transport-dominated failure modes with near-linear acceleration in total mass transfer. This paper discusses the general and specific aspects of biased MFG testing of electronic systems and provides a case study of field failures illustrating the need for this type of testing as a regular part of system qualification.

East-West Design&Test Workshop

This report discusses the 2006 IEEE East-West Design & Test International Workshop, held 15 to 19 September 2006 in Sochi, Russia. The goal of the workshop was to exchange experience in design and test of electronic systems among scientific experts from Eastern and Western Europe, as well as other parts of the world.

2005 IEEE East-West Design and Test Workshop

The 3rd IEEE East-West Design and Test Workshop (EWDTW 2005) took place from 15 to 19 September in Odessa, Ukraine. The workshop's goal was for scientific schools and experts in Eastern and Western Europe (as well as other parts of the world) to exchange experiences in the design and test of electronic systems. Researchers from western countries presented an overview of design-and-test trends. André Ivanov gave a tutorial on network-on-chip design and test, and Yervant Zorian gave a tutorial on design for yield and reliability. Participants from Intel presented the invited talk, "Research at Intel's Strategic CAD Labs," which gave an overview of CAD research preformed at Intel's laboratories.

Mastering and Archiving Uncompressed Digital Video Test Materials

This is a report on the status of the SMPTE Ad Hoc Group (AHG) charged with creating a master set of standard-definition video sequences for subjective testing of electronic systems. The images will be available from SMPTE, for use in the evaluation of electronic systems. The first task is to create a master representation of video sequences enabling preservation in a consistent and stable storage environment. Once the sequences are restored and returned to a pristine state (when possible), they will be provided in digital file format to SMPTE. The Society will then offer the video sequences in various formats (digital data media and uncompressed digital videotape) for testing electronic systems. This report also includes representative images from sequences in a set of standard-definition materials, the first production of the AHG. Finally, feedback and suggestions on the quality and interest of this process is requested.

Image quality parameters for the production standard Eliav PORTpro portal imaging device.

Measurements of the high contrast spatial resolution and contrast-to-noise ratio of the production standard Eliav "PORTpro" portal imaging system have been made using a commercially available quality assurance phantom. The spatial resolution of the images is comparable with published data for other commercial systems, but somewhat lower than that published previously for the prototype of this system. These data may be of use to those involved in the selection, commissioning or quality assurance testing of electronic portal imaging systems.

Thermal monitoring and testing of electronic systems

The paper presents a method for online overheating protection of electronic systems. The key elements of the implementation, the thermal sensor and a chip dedicated to thermal monitoring of the various components are presented in details. Beyond on line thermal monitoring, offline static and transient thermal testing are also enabled by the suggested method, using the standard test circuitry and boundary scan.

Printed circuit board diagnosis using artificial neural networks and circuit magnetic fields

Testing of electronic systems using conventional testing methods has become more difficult and costly as these systems have become more complex and compact. Conventional testing methods and systems often require lengthy analysis to define testing strategies. These test systems may require lengthy test periods, complex stimulus and measurement instrumentation as well as complicated fixturing. The results are often ambiguous and require further interpretation. This paper presents an exploration of a "non-intrusive" test method based on interpreting changes in the magnetic field close to a Printed Circuit Board (PCB). Currents moving between devices on the PCB produce these magnetic fields. Changes of the PCB operational status due to faults cause changes in the associated magnetic field pattern that can be interpreted by Artificial Neural Networks (ANNs) for fault identification. An apparatus to collect magnetic field measurements is described along with some problems of collecting data. Typical magnetic field patterns for "known-good" and faulted PCBs are presented. Possible extensions of the method are discussed. This paper resulted from internally funded work at Southwest Research Institute (SwRI) concerning non-intrusive diagnostic techniques.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

The impact of NRZ data asymmetry on the performance of a space telemetry system

The author derives an expression for the power spectral density of an asymmetric nonreturn-to-zero (NRZ) data stream. This formula is used to investigate how the data bandwidth varies with data asymmetry. The threshold levels of undesired spectral components that fall into the carrier tracking loop bandwidth are determined by examining the derived spectral density. Based on this formula, a simple technique is developed for the computation of bit signal-to-noise ratio (SNR) degradation due to data asymmetry. The telemetry bit SNR degradations derived using this technique are compared with the results obtained previously by M.K. Simon et al. (1978) and with measurements by the electronic systems test laboratory (ESTL) at the Lyndon B. Johnson Space Center.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Intermittent fault coverage during test of electronic components and systems

Fault-detection experiments for electronic components and systems are usually designed for the detection of permanent or data-dependent faults. Treatment of intermittent faults in the literature has been restricted to the use of Markov models for the design of fault experiments capable of detecting intermittent faults having specified transition probabilities. In the letter a transformation has been introduced allowing an estimation of the fault coverage of a particular test strategy to be made without assumptions about the characteristics of likely faults.

Shuttle Communication Systems Compatibility and Performance Testing

The Shuttle communications system consists of major space and ground elements. The space elements include the Orbiter, Tracking and Data Relay Satellite, payload and extravehicular astronaut communications subsystems. The Spaceflight Tracking and Data Network, relay satellite ground segment, and the Air Force Satellite Control Facility make up the major ground elements of the communications system. The compatibility and performance of each of these major elements functioning as a complete system must be certified prior to operational missions. Unique Shuttle communication channels employing spread spectrum techniques, high rate data (50 Mbits/s), convolutional encoding, and unbalanced quadriphase modulation must be evaluated on an end-to-end RF (radio frequency) system basis. To accomplish the necessary communication system compatibility and performance tests, NASA has established the ESTL (Electronic Systems Test Laboratory) at the Lyndon B. Johnson Space Center. This paper discusses the Shuttle communication systems compatibility and performance testing which is being accomplished at the ESTL. The system test philosophy for the complex communications channels is described in terms of the major phases which include early breadboard system design evaluation tests, system verification tests with prototype hardware and system certification testing with qualifiable (flight) hardware. The system hardware configuration, facility requirements, test and evaluation techniques and operational approaches required to accomplish each major phase of testing are reviewed. Results of recently completed space-to-space and space-space-to-ground system tests are presented. Test techniques and measurement accuracies proven over 10 years of system evaluation experience unique to the ESTL are reviewed. Techniques used in relating experimental system performance and predicted system performance (based on hardware math models), and conclusions regarding effectiveness of system level testing of such complex hardware are addressed.

Automated spectrum analysis

Automatic spectrum analyzers (ASA's) combine a powerful RF measurement system with computer control and data processing. This article discusses a typical ASA block diagram (analog and digital subsystems), shows how the calibration procedures used in such systems enhance the accuracy of measurements, and discusses some of the problems with current ASA systems. The present use of ASA systems in government and industry is illustrated with several examples of ASA systems used in production testing of large electronic systems, measurements of the electromagnetic environment, communication satellite monitoring, and EMC testing. Finally, alternate technologies for making spectrum measurements and the future of ASA's are discussed.

Staggered testing of electronic systems revisited : Winfrid G. Schneeweiss. Microelectron. Reliab.17, 523 (1978)

Staggered testing of electronic systems revisited : Winfrid G. Schneeweiss. Microelectron. Reliab.17, 523 (1978)

Staggered testing of electronic systems revisited

For the simplest case of redundancy being the 1-out-of-2 system the interesting concept of staggered testing is revisited. System MTBF is derived in a conceptually and mathematically new way. Also, system MTTR is re-derived from basic concepts. All results apply for systems of periodically renewed subsystems and also for systems of periodically checked subsystems with exponential life distribution.

Automatic testing of electronic systems

The great expansion in the use of electrical and electronic equipment over the past few years has imposed an increasing problem of testing and maintenance on both the manufacturer and the operator. Automatic test equipment can to a large degree solve this problem by increasing the speed and reliability of testing methods and by reducing the manpower involved. The author suggests that in the near future automatic testing will find other applications in expanding fields such as navigation, connumication, pneumatic and hydraulic systems.

A Self-Programming Automatic Electronic Test System with Pattern Recognition Displays

Employing a large number of optical and electrical input signals an automatic test system is proposed which rapidly samples the test data from an operating ensemble and which then displays the data in block form so that interpretation is made on the basis of pattern recognition. The display is via a cathode ray tube which is operated in a TV mode so that the displayed test data can be continuously and rapidly up-dated. By means of rear ports in the CRT it is shown how failure patterns can be recorded on film and preserved to make the test system self-programming, thereby overcoming one of the major obstacles in presently conceived automatic test systems.

Aviation Electronics

Blackburn Electronics Ltd. have developed and produced a universal ‘Tape‐controlled Recording and Automatic Check‐out Equipment’ (T.R.A.C.E.) for prc‐flight and maintenance testing of electronic and electrical systems. T.R.A.C.E. has been designed to operate in the first instance with the ‘Buccaneer’, the low‐level strike aircraft in production for the Royal Navy. The Company is now negotiating further Government and industrial contracts.