Fault Localization of Power-Ground Short via Signal Injection and Oscilloscope Technique

2010 ◽  
Author(s):  
Binh Nguyen
Keyword(s):  
Low Cost ◽  
Short Circuit ◽  
Fault Localization ◽  
Fault Isolation ◽  
Test Apparatus ◽  
Good Working ◽  
Signal Injection ◽  
Set Up ◽  
Non Destructive ◽  
Short Circuit Condition

Abstract For those attempting fault isolation on computer motherboard power-ground short issues, the optimal technique should utilize existing test equipment available in the debug facility, requiring no specialty equipment as well as needing a minimum of training to use effectively. The test apparatus should be both easy to set up and easy to use. This article describes the signal injection and oscilloscope technique which meets the above requirements. The signal injection and oscilloscope technique is based on the application of Ohm's law in a short-circuit condition. Two experiments were conducted to prove the effectiveness of these techniques. Both experiments simulate a short-circuit condition on the VCC3 power rail of a good working PC motherboard and then apply the signal injection and oscilloscope technique to localize the short. The technique described is a simple, low cost and non-destructive method that helps to find the location of the power-ground short quickly and effectively.

Verification of DLS Data by LVP in Case of Marginal Failure

2016 ◽  
Author(s):  
Keonil Kim ◽  
Sungjin Kim ◽  
Kunjae Lee ◽  
Kyeongju Jin ◽  
Yunwoo Lee ◽  
...  
Keyword(s):  
Failure Analysis ◽  
Failure Mechanism ◽  
Fault Location ◽  
Photon Emission ◽  
Fault Localization ◽  
Fault Isolation ◽  
The Real ◽  
Defect Isolation ◽  
The Relationship ◽  
Non Destructive

Abstract In most of the non-destructive electrical fault isolation cases, techniques such as DLS, Photon Emission, LIT, OBIRCH indicate a fault location directly. But relying on just one of these techniques for marginal failure mechanism is not enough for better fault localization. When Failure Analysis (FA) engineers encounter high NDF (No Defect Found) rates, by using only one of the techniques, they may need to consider the relationship between the responded locations by different techniques and fail phenomenon for better defect isolation. This paper talks about how a responded DLS location does not always indicate a fault location and how LVP data collected using DLS location can pin point the real defect location.

scholarly journals A Comparison among Different Ways to Investigate Composite Materials with Lock-In Thermography: The Multi-Frequency Approach

Materials ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2525
Author(s):  
Ester D’Accardi ◽  
Davide Palumbo ◽  
Umberto Galietti
Keyword(s):  
Low Cost ◽  
Fiber Reinforced Polymers ◽  
Non Destructive Testing ◽  
Destructive Testing ◽  
Carbon Fiber Reinforced Polymers ◽  
Reinforced Polymers ◽  
Advantages And Disadvantages ◽  
Set Up ◽  
Lock In ◽  
Non Destructive

The main goal of non-destructive testing is the detection of defects early enough to avoid catastrophic failure with particular interest for the inspection of aerospace structures; under this aspect, all methods for fast and reliable inspection deserve special attention. In this sense, active thermography for non-destructive testing enables contactless, fast, remote, and not expensive control of materials and structures. Furthermore, different works have confirmed the potentials of lock-in thermography as a flexible technique for its peculiarity to be performed by means of a low-cost set-up. In this work, a new approach called the multi-frequency via software approach (MFS), based on the superimposition via software of two square waves with two different main excitation frequencies, has been used to inspect a sample in carbon fiber reinforced polymers (CFRP) material with imposed defects of different materials, sizes and depths, by means of lock-in thermography. The advantages and disadvantages of the multi-frequency approach have been highlighted by comparing quantitatively the MFS with the traditional excitation methods (sine and square waves).

In-SEM Fault Isolation Using Voltage Contrast, EBIC/EBAC and Resistive Contrast Imaging

2020 ◽  
Author(s):  
Lori L. Sarnecki ◽  
Caleb Daigneault
Keyword(s):  
Semiconductor Device ◽  
Photon Emission ◽  
Fault Localization ◽  
Spot Size ◽  
Fault Isolation ◽  
Contrast Imaging ◽  
Laser Signal ◽  
Signal Injection ◽  
Voltage Contrast ◽  
Optical Level

Abstract With the ever shrinking semiconductor device features coupled with the increasing circuit density, optical level fault localization techniques such as Photon Emission Microscopy (PEM), Laser Signal Injection Microscopy (LSIM) and Thermal Hotspot Localization (THS) can only get you so far due to these limitations: magnification, spot size and drop in detection sensitive at higher magnification. Using a 100x objective can put you in the ball park. Test data such as ATE & ATPG can point you to a specific block of circuitry but still far from defect localization. With in-SEM fault isolation and localization techniques such as Voltage Contrast (VC), Electron Beam Induced/Absorb Current (EBIC/EBAC) and Resistive Contrast Imaging (RCI), the nano-scale defect can be further localized due to the advantage of the magnification and spot size. This paper offers the combined techniques of optical level fault localization (PEM, LSIM & THS) and in- SEM or E-beam techniques (VC, EBAC, RCI) to successfully perform fault localization when challenged with the above scenarios.

Numerical Calculation of Short Circuit Electromagnetic Force in Isolated Phase Bus

2014 ◽  
Vol 986-987 ◽  
pp. 944-947
Author(s):  
Tusong Jiang Kari ◽  
Xi Wang Abuduwayiti ◽  
Ming Ma
Keyword(s):  
Numerical Calculation ◽  
Periodic Function ◽  
Phase Angle ◽  
Proximity Effect ◽  
Electromagnetic Force ◽  
Short Circuit ◽  
Current Phase ◽  
Transient Method ◽  
Set Up ◽  
Short Circuit Condition

Short circuit electromagnetic forces are one of the most important factors in design and operation of buses. 2D infinite element models are set up with ANSOFT for isolated phase buses, simulating with transient method and calculating short circuit electromagnetic force taking eddy effect and proximity effect into account. The result reveals that the maximum electromagnetic force under short circuit condition is a periodic function of current phase angle.

Numerical Analysis on Short-Circuit Force Parameters of Windings for Power Transformer

2011 ◽  
Vol 138-139 ◽  
pp. 764-769
Author(s):  
Jian Jun Liu ◽  
Jian Min Wang ◽  
Chong You Jing ◽  
Chang Zai Fan ◽  
Yuan Zhai
Keyword(s):  
Magnetic Field ◽  
Numerical Analysis ◽  
Power Transformer ◽  
Short Circuit ◽  
Strength Test ◽  
Power Transformers ◽  
Simplified Model ◽  
Leakage Magnetic Field ◽  
Set Up ◽  
Short Circuit Condition

The Simplified model of both calculating leakage magnetic field and mechanical force of windings at short circuit condition for a 120MVA/220kV power transformer is set up. The leakage magnetic field ‚ short-circuit force and stress in transformer windings are analyzed and their distributing characteristics are acquired respectively by using FEM. The calculation method and results are validated by withstanding short circuit strength test of the product. A number of useful suggestions are given for design of power transformers.

Development of a Capacitor Probe to Detect Subsurface Deterioration in Concrete

1997 ◽  
Vol 503 ◽  
Author(s):  
B. K. Diefenderfer ◽  
I. L. Al-Qadi ◽  
J. J. Yoho ◽  
S. M. Riad ◽  
A. Loulizi
Keyword(s):  
Dielectric Constant ◽  
Portland Cement ◽  
Electromagnetic Waves ◽  
Low Cost ◽  
Complex Dielectric Constant ◽  
Life Cycle Costs ◽  
Parallel Plates ◽  
Portland Cement Concrete ◽  
Cement Concrete ◽  
Set Up

ABSTRACTPortland cement concrete (PCC) structures deteriorate with age and need to be maintained or replaced. Early detection of deterioration in PCC (e.g., alkali-silica reaction, freeze/thaw damage, or chloride presence) can lead to significant reductions in maintenance costs. However, it is often too late to perform low-cost preventative maintenance by the time deterioration becomes evident. By developing techniques that would enable civil engineers to evaluate PCC structures and detect deterioration at early stages (without causing further damage), optimization of life-cycle costs of the constructed facility and minimization of disturbance to the facility users can be achieved.Nondestructive evaluation (NDE) methods are potentially one of the most useful techniques ever developed for assessing constructed facilities. They are noninvasive and can be performed rapidly. Portland cement concrete can be nondestructively evaluated by electrically characterizing its complex dielectric constant. The real part of the dielectric constant depicts the velocity of electromagnetic waves in PCC. The imaginary part, termed the “loss factor,” describes the conductivity of PCC and the attenuation of electromagnetic waves.Dielectric properties of PCC have been investigated in a laboratory setting using a parallel plate capacitor operating in the frequency range of 0.1 to 40.1MIHz. This capacitor set-up consists of two horizontal-parallel plates with an adjustable separation for insertion of a dielectric specimen (PCC). While useful in research, this approach is not practical for field implementation. A new capacitor probe has been developed which consists of two plates, located within the same horizontal plane, for placement upon the specimen to be tested. Preliminary results show that this technique is feasible and results are promising; further testing and evaluation is currently underway.

Advance Protection for Three Phase Induction Motor using Microcontroller Atmega32

2018 ◽  
Vol 8 (1) ◽  
pp. 172
Author(s):  
Karan S Belsare ◽  
Gajanan D Patil
Keyword(s):  
Induction Motor ◽  
Low Cost ◽  
Short Circuit ◽  
Cost Factor ◽  
Protection Scheme ◽  
Three Phase ◽  
The Cost

A low cost and reliable protection scheme has been designed for a three phase induction motor against unbalance voltages, under voltage, over voltage, short circuit and overheating protection. Taking the cost factor into consideration the design has been proposed using microcontroller Atmega32, MOSFETs, relays, small CTs and PTs. However the sensitivity of the protection scheme has been not compromised. The design has been tested online in the laboratory for small motors and the same can be implemented for larger motors by replacing the i-v converters and relays of suitable ratings.

Advanced T-LSIM System Detections using Amplified External Isolated Source-Sense Unit

2018 ◽  
Author(s):  
Zhi Jie Lau ◽  
Chris Philips
Keyword(s):  
Fault Isolation ◽  
Isolation Technique ◽  
Laser Signal ◽  
Signal Injection ◽  
Sense Unit ◽  
Types Of Faults

Abstract Thermal-Laser Signal Injection Microscopy (T-LSIM) is a widely used fault isolation technique. Although there are several T-LSIM systems on the market, each is limited in terms of the voltage and current it can produce. In this paper, the authors explain how they incorporated an Amplified External Isolated Source-Sense (AxISS) unit into their T-LSIM platform, increasing its current sourcing capability and voltage biasing range. They also provide examples highlighting the types of faults and failures that the modified system can detect.

Advanced Non-Destructive Fault Isolation Techniques for PCB Substrates Using Magnetic Current Imaging and Terahertz Time Domain Reflectometry

2018 ◽  
Author(s):  
Daechul Choi ◽  
Yoonseong Kim ◽  
Jongyun Kim ◽  
Han Kim
Keyword(s):  
Time Domain ◽  
Quantum Interference ◽  
Flip Chip ◽  
Imaging System ◽  
Time Domain Reflectometry ◽  
Fault Isolation ◽  
Magnetic Current ◽  
Isolation Techniques ◽  
Super Conducting ◽  
Non Destructive

Abstract In this paper, we demonstrate cases for actual short and open failures in FCB (Flip Chip Bonding) substrates by using novel non-destructive techniques, known as SSM (Scanning Super-conducting Quantum Interference Device Microscopy) and Terahertz TDR (Time Domain Reflectometry) which is able to pinpoint failure locations. In addition, the defect location and accuracy is verified by a NIR (Near Infra-red) imaging system which is also one of the commonly used non-destructive failure analysis tools, and good agreement was made.

Low Temperature Fault Isolation Using Soft Defect Localization

2012 ◽  
Author(s):  
Kristopher D. Staller
Keyword(s):  
Low Temperatures ◽  
Laser Scanning ◽  
Low Cost ◽  
Fault Isolation ◽  
Laser Scanning Microscopy ◽  
Cold Temperature ◽  
Multiple Point ◽  
Defect Localization ◽  
Low Levels

Abstract Cold temperature failures are often difficult to resolve, especially those at extreme low levels (< -40°C). Momentary application of chill spray can confirm the failure mode, but is impractical during photoemission microscopy (PEM), laser scanning microscopy (LSM), and multiple point microprobing. This paper will examine relatively low-cost cold temperature systems that can hold samples at steady state extreme low temperatures and describe a case study where a cold temperature stage was combined with LSM soft defect localization (SDL) to rapidly identify the cause of a complex cold temperature failure mechanism.

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