Gideon Analytical Laboratories received several VCSELs (vertical cavity surface emitting laser" with diminished light capacity over time for failure analysis. VCSELs are a type of semiconductor laser diode with laser beam emission perpendicular from the chip surface. The VCSEL has become of great importance in the optical communications field. Gideon Analytical Laboratories was tasked to diagnose the failing VCSELs.
Failure analysis commenced. The devices were tested on a curve tracer to determine whether any junction problems (junction inversion, leakage current, facet oxidation, etc.
Gideon Analytical Laboratories received one static transfer switch (STS) Main Logic printed circuit board (PCB) assembly with two chips onboard digital signal processor (DSP)’s that were non-functional. The thought was the DSPs may have ball grid array (BGA) solder joint integrity issues causing the failures.
Analysis ensued. The three DSPs were removed from the PCB and immersed into the green dye and the DSP was pried from the main circuit board to reveal any cracked solder BGAs.
Gideon Analytical Laboratories received 19 multilayered ceramic capacitors (MLCCs). MLCCs have a ceramic dielectric, a ceramic or lacquered coating, a metalized electrode, and connecting terminals. Ceramic capacitors, in particular, MLCCs, are ubiquitous in all kinds of electrical equipment. Some of the MLCCs Gideon received were to test quality control, some were to test process evaluation immediately after wave solder, and some were failures in the field. The objective was to determine where these failures were entering the product and the cause of the failures.
Gideon Analytical Laboratories received three failed Vishay MOC8101 isolating photocouplers for failure analysis. These photocouplers are components that transfer electrical signals between two isolated circuits by using light. Like the MOC8102, MOC8103, MOC8104, and MOC8105, the MOC8101 consists of a consisting of gallium arsenide infrared emitting diode optically coupled to a silicon planar phototransistor detector in a plastic plug-in DIP-6 package (http://www.vishay.com/docs/83660/moc8101.pdf) The MOC8101 were reported to have intermittent function, it was the goal of Gideon Analytical Laboratories to diagnose the cause of these failures.
Gideon Analytical Laboratories received three axial-lead resistors for failure analysis (pictured in the first picture directly below). A resistor is a passive two-terminal electrical component that implements electrical resistance as a circuit element. Their purpose is for creating a precise quantity of resistance for insertion into a circuit; they are typically constructed of metal wire or carbon and engineered to maintain a stable resistance value over a wide range of environmental conditions.
Gideon Analytical Laboratories received several GVD30601-001 super hyperabrupt junction tuning varactor diodes with a latent failure mechanism over time. A varactor diode is a P-N junction diode that changes its capacitance and the series resistance as the bias applied to the diode is varied. Hyperabrupt tuning varactor diodes offer a large change in junction capacitance over a small tuning voltage range. Varactors are operated in a reverse-bias state, like a Zener diode.
Gideon Analytical Laboratories received to MR16 sockets for a comparison between the current model and a new candidate. The MR16s are a type of bi-pin lamp fitting. Bi-pin lamp fittings are for use in incandescent (especially halogen) and some fluorescent lights. Gideon Analytical Laboratories not only helps companies identify the causes of failures in the manufacturing process and the field but in this case, can help identify positives and negatives about a type of design or types of materials.
Gideon Analytical Laboratories received six MLCC on power cards. MLCC are multilayer ceramic capacitors. A ceramic capacitor is fixed value capacitor with the ceramic material acting as the dielectric. They have two or more alternating layers of ceramic and metal acting as electrodes. Two MLCCs were identified as failures and four MLCCs were to determine whether “flexiterm” terminations were used.
All six capacitors were removed from the power boards and tested for capacitance, ESR, and leakage current.
Gideon Analytical Labs received four Maxim 4252EUA dual op-amps for failure analysis. Operational Amplifiers or Op-amps are one of the basic building blocks of analog electronic circuits. Operational amplifiers are linear devices that have all the properties required for nearly ideal DC amplification and are therefore used extensively in signal conditioning, filtering or to perform mathematical operations such as add, subtract, integration and differentiation. It was reported the fails indicated no output.
Gideon Analytical Labs received two failed 510K, two used 510K operating for about 3 weeks, and two virgin resistors for failure analysis. A resistor is a component of a circuit that resists the flow of electrical current. It has two terminals across which electricity must pass, and it is designed to drop the voltage of the current as it flows from one terminal to the other. Resistors are primarily used to create and maintain known safe currents within electrical components.
