Gideon was asked to perform a failure analysis on two Vishay SQD50P04-13L MOSFETs in TO-252 packages. The failed MOSFETs arrived on two PCBs.
There was no external damage to the package on either Q27 or Q14.
Since MOSFETs typically fail with all terminals shorted, it is imperative to examine the remainder of the die for evidence that may or may not be present to determine a cause for the EOS.
Gideon Analytical Laboratories received several Avago HCPL-2202 Optocouplers for failure analysis. These optocouplers have a totem pole output stages and optical receiver input stages with built-in Schmitt triggers to provide logic-compatible waveforms. They feature low input current (1.6mA to 1.8mA), Mbd typical signal rate, and guaranteed performance from -40 to 85 degrees Celsius. Some of their applications include isolation of high-speed logic systems, microprocessor system interfaces, and ground loop elimination. Our goal was to determine why the Avago HCPL-2202 Octocouplers had been failing.
Gideon Analytical Laboratories received one TI TPS767D301 dual-output low-dropout voltage regulator with a ground to reset short The TI TPS767D301 offers a transient response, low dropout voltages, and dual outputs. It is designed primarily for DSP applications. It features extended temperature performance from 55 to 125 degrees Celsius, drop out voltage typically 350 mV at 1 A, and enhanced product-change notification. The goal was to determine why these TI TPS767D301 voltage regulators were failing, paying special attention to the ground to reset short.
Gideon Analytical Laboratories received several RY4S-UAC110-120V power relays for failure analysis. A relay is an electrically operated switch. Many relays use an electromagnet to operate the switch, but other operating principles are also used, such as solid-state relays. Relays are used where it is necessary to control a circuit by a separate low-power signal, or where several circuits must be controlled by one signal. Relays are used to control a high power or high voltage circuit with a low power circuit.
Gideon Analytical Laboratories received a TI TMS320F28335PGFA Digital Signal Processor for failure analysis. Digital Signal Processing applications include audio and speech processing,sonar,radar, and other sensor array processing,spectral density estimation,statistical signal processing,digital image processing, among many others. The TI TMS320F28335PGFA features high-performance static CMOS technology, a 32-bit CPU, 16 x 16 and 32 x 32 MAC operations, and Harvard bus architecture. It has up to 88 individually programmable, multiplexed GPIO pins with input filtering.
Gideon Analytical Laboratories received three different vendor 100-ohm resistors, made by Vishay, RCD, and Stackpole, respectively. The two Stackpole resistors were open. A resistoris a passive two-terminal electrical component that implements electrical resistance as a circuit element. In electronic circuits, resistors are used to reduce current flow, adjust signal levels, to divide voltages, bias active elements, and terminate transmission lines, among other uses. Our goal was to test the functionality the Vishay, RCD, and Stackpole resistors, and if any were failing, determine the cause of the failure.
Gideon Analytical Laboratories received several T491D475K050AT Kemet tantalum capacitors for electronic failure analysis. A capacitor is a passive two-terminal electronic component that stores electrical energy in an electric field. While some capacitance exists between any two electrical conductors in proximity in a circuit, a capacitor is a component designed to add capacitance to a circuit. The Kemet T491D475K050AT has a capacitance of 4.7 uF, a voltage rating of 50 VDC, and a tolerance of 10%, measures 7.
Gideon Analytical Laboratories received two 1N645 silicon rectifier diodes for failure analysis. One was bad and the other was a quality diode to be used for comparison. A rectifier is an electrical device that converts alternating current(AC), which periodically reverses direction, to direct current(DC), which flows in only one direction. Rectifiers are used inside the power supplies of virtually all electronic equipment. AC/DC power supplies may be broadly divided into linear power supplies ands witched-mode power supplies.
Gideon Analytical Laboratories received several Murata Electronics GCM21BR70J106KE22L Multi-Layered Ceramic Capacitors (MLCCs) for failure analysis. An MLCC consists of a number of individual capacitors stacked together in parallel and contacted via the terminal surfaces. The starting material for all MLCC chips is a mixture of finely ground granules of paraelectric or ferroelectric raw materials, modified by accurately determined additives. The Murata Electronics GCM21BR70J106KE22L has a capacitance of 10 uF, a DC voltage rating of 6.
Gideon Analytical Laboratories received two On Semiconductor SS16 rectifier for failure analysis. The On Semiconductor SS16 Schottky Rectifier features glass-passivated junctions and a high-current capacity. Their applications include low voltage, high-frequency inverters, freewheeling, and polarity protection. Their storage temperature range is between -65 and 150 Degrees Celsius and the operating junction temperature is between -65 and 125 Degrees Celsius. Along with the two failed rectifiers, several good devices were also supplied for comparison.
Gideon Analytical Laboratories received two Sunon Maglev MC35101V2-000U-G99 12V fans which did not operate. Along with the nonoperational fans, two functional fans were also sent to us for comparison. The Sunon Maglev MC35101V2-000U-G99 12V fan is an axial DC fan, with a speed of 7500 RPM and airflow of 6.5 CFM. An axial fan is a type of fan that causes gas to flow through it in an axial direction, parallel to the shaft about which the blades rotate.
Gideon Analytical Laboratories received four Vishay CRCW2512220RJNEG thick film chip resistors to be analyzed. Thick film resistors are the most used resistors in electrical and electronic devices. The resistive material is a special paste with a mixture of a binder, a carrier, and the metal oxides to be deposited. These Vishay CRCW2512220RJNEG resistors thick film chip resistors feature stability at different environmental conditions and 2mm pitch packaging option for 0603 sizes.
Gideon Analytical Laboratories received two LUMEX SSL-LX093UWC/Gc LEDs for failure analysis. A LED (Light Emitting Diode), is a semiconductor light source that emits light when current flows through it. LEDs can be used in many different applications. Electrons in the semiconductor recombine with electron holes, releasing energy in the form of photons. Some of the more creative uses include creating an LED virtual sky, LED bionic contact lenses, and LED wallpaper.
Gideon Analytical Laboratories received six pulse transformer. Three were good, three were failures. Transformers can be thought of as an electrical component rather than an electronic component. A transformer basically is very simple static (or stationary) electro-magnetic passive electrical device that works to convert electrical energy from one value to another. The transformer does this by linking together two or more electrical circuits using a common oscillating magnetic circuit which is produced by the transformer itself.
Gideon Analytical Laboratories received a programmable logic device (PLD) P18586P for failure analysis. A programmable logic device is an electronic component used to build reconfigurable digital circuits. Unlike a logic gate, which has a fixed function, a PLD has an undefined function at the time of manufacture. Before the PLD can be used in a circuit it must be programmed. A PLD is a combination of a logic device and a memory device.
Gideon Analytical Laboratories received six United Chemi-Con KMG series 400V 22uF 6U capacitors for the specific purpose of determining whether or not they had the presence of chlorides.
The analysis was performed using SEM-EDS. The SEM-EDS system gave elemental analysis in relation to the intensity of the element at a specific wavelength or energy level (Kev). SEM-EDS is an analytical technique used for the elemental analysis or chemical characterization of a sample.
Gideon Analytical Laboratories received several high-intensity discharge lamp (HID) assemblies for determination and cause of a white powder-like substance on the inside of the lens housing. The white powder diminishes the reflective properties of the light and overall effectiveness. HID lamps are a type of electrical gas-discharge lamp which produces light by means of an electric arc between tungsten electrodes housed inside a translucent or transparent fused quartz or fused alumina arc tube.
Gideon Analytical Laboratories received 22 EEPROM devices for analysis of the lead plating. EEPROM stands for electrically erasable programmable read-only memory and is a type of non-volatile memory used in computers and other electronic devices to store relatively small amounts of data but allowing individual bytes to be erased and reprogrammed. EEPROMs are organized as arrays of floating-gate transistors. EEPROMs can be programmed and erased in-circuit, by applying special programming signals.
Gideon Analytical Laboratories received two Fairchild RV4140A Ground Fault Interrupt Controller/Monitors in eight-pin SOIC packages. The Fairchild RV4140A is low power controller for AC outlet appliance leakage circuit interrupters. These devices detect hazardous current paths to ground such as an appliance falling into water. The interrupter then opens the circuit before a harmful or lethal shock occurs. A SOIC package is a surface-mounted integrated circuit (IC) package which occupies an area about 30 to 50 % less than an equivalent dual in-line package (DIP), with a typical thickness that is 70 % less.
Gideon Analytical Laboratories received two metal castings. One was a cylinder and the other was an insert to the bottom of the cylinder. Metal means a process, in which liquid metal is poured into a mold, that contains a hollow cavity of the desired shape, and then allowed to cool and solidify. The solidified part is also known as a casting, which is ejected or broken out of the mold to complete the process.
Gideon Analytical Laboratories received two newly designed ST Microelectronics ASC T6108 Triacs in a TO-220AB package. A TRIAC is a three terminal semiconductor device for controlling current.Its formal name is bidirectional triode thyristor or bilateral triode thyristor. A thyristor is analogous to a relay in that a small voltage and current can control a much larger voltage and current. The goal was to determine if these ASC T6108 Triacs were reliable.
Gideon Analytical Analytical Laboratories received one On Semi MC14070BG CMOS SSI in a SOEIAJ-14 package, with the 15V supply line pulled down to 3.5V. The MC14070B quad exclusive OR gate and the MC14077B quad exclusive NOR gates are constructed with MOS P−channel and N−channel enhancement mode devices in a single monolithic structure. These complementary MOS logic gates find primary use where low power dissipation and/or high noise immunity is desired. The CMOS is a Complementary metal–oxide–semiconductor, which is a technology for constructing integrated circuits.
Gideon Analytical Laboratories received several rigid-flex printed circuit boards (PCBs), which containedTexas Instruments TPS54360 DC-DC converter and Micro Commercial Components Schottky rectifier SK810L-TP. The TI TPS54360 is a 60 V, 3.5 A, step down regulator with an integrated high side MOSFET. The device survives load dump pulses up to 65V per ISO 7637. Current mode control provides simple external compensation and flexible component selection. The SK810L-TP is Rohs compliant, has high current availability, and is for surface mount application.
Gideon Analytical Laboratories received two components for analysis. We received one 10TTS08S phase control silicon controlled rectifier (SCR) and an FDC6324L integrated load switch. A silicon controlled rectifier (SCR) is a four-layer solid-state current-controlling device. It consists of four layers of semiconductors, which form NPNP or PNPN structures have three P-N junctions labeled J1, J2 and J3, and three terminals. The anode terminal of an SCR is connected to the p-type material of a PNPN structure, and the cathode terminal is connected to the n-type layer, while the gate of the SCR is connected to the p-type material nearest to the cathode.
Gideon Analytical Laboratories received one section of the anode electrode to identify the black marking on the copper foil. This anode electrode is used in Lithium-ion batteries. A Lithium-ion battery is a type of rechargeable battery in which lithium ions move from the negative electrode to the positive electrode during discharge and back when charging. Lithium-ion batteries use an intercalated lithium compound as one electrode material, compared to the metallic lithium used in a non-rechargeable lithium battery.
Gideon Analytical Laboratories received a Printed Circuit Board (PCB) with contamination on several capacitor sleeves, connector pins, and an oscillator. An electrolytic capacitor is a capacitor whose anode (+) consists of pure aluminum foil with an etched surface, covered with a uniformly very thin barrier layer of insulating aluminum oxide, which operates as a dielectric. The electrolyte, which covers the rough surface of the oxide layer, operates as the second electrode, the cathode (-).
Gideon Analytical Laboratories received one IXYSRF DE375-501N21A MOSFET for electronic failure analysis. A MOSFET is a type of field-effect transistor (FET). It has an insulated gate, whose voltage determines the conductivity of the device. This ability to change conductivity with the amount of applied voltage can be used for amplifying or switching electronic signals. The IXYSRF DE375-601N21A MOSFET has high dv/dt, nanosecond switching, and 50 MHz maximum frequency. The IXYSRF DE375-601N21A MOSFET sent to Gideon Analytical Laboratories had a g-s short.
Gideon Analytical Laboratories received five failed ST Microelectronics BTA16-800 triacs and one good ST Microelectronics BTA16-800 triac for comparison. A triac is a generic trademark for a three terminal electronic component that conducts current in either direction when triggered. Its formal name is bidirectional triode thyristor or bilateral triode thyristor. The goal was to determine the cause of these failures.
Gideon Analytical Laboratories went straight to work conducting failure analysis on theST Microelectronics BTA16-800 triacs.
Gideon received ultra precision calibration resistors. These resistors have a tolerance of .1%. The ultra precision thin film resistors are designed for high precision circuitry. They have excellent stability and reliability over the operating temperature range and low TCR characteristics.
The resistors were running about .3 to .4 ohm too high.
Onboard Test 1 Test 2 Test 3 Test 4 Test 5 decapsulated Halogens PCB1 100.
Gideon Analytical Laboratories received two Vishay phototriac 4208s for failure analysis. A TRIAC is a generic trademark for a three-terminal electronic component that conducts current in either direction when triggered. Its formal name is bidirectional triode thyristor or bilateral triode thyristor. A thyristor is analogous to a relay in that a small voltage and current can control a much larger voltage and current.TRIACs are a subset of thyristors and are related to silicon controlled rectifiers(SCRs).
Gideon Analytical Laboratories received four Vishay SS26 Surface Mount Schottky Barrier Rectifiers for possible premature conditions to failure. A Schottky barrier is a potential energy barrier for electrons formed at a metal-semiconductor junction. Schottky barriers have rectifying characteristics, suitable for use as a diode. These Vishay SS26 Surface Mount Schottky Barrier Rectifiers feature a low profile package, high surge capability, and are RoHS compliant. The diodes came from PCB P/N 170310142001 Rev A03 S/N 051208-231.
Gideon Analytical Laboratories received one Honeywell SS466A Hall effect sensor encapsulated in epoxy for failure analysis. A Hall effect sensor is a transducer that varies its output voltage in response to a magnetic field. Hall effect sensors are used for proximity switching, positioning, speed detection, and current sensing applications. In a Hall effect sensor, a thin strip of metal has a current applied along it, in the presence of a magnetic field the electrons are deflected towards one edge of the metal strip, producing a voltage gradient across the short side of the strip (perpendicular to the feed current).
Gideon received two failed NEC 104PW161 inverter boards with Micro Fuse chip circuit protectors failing. Rather than performing a failure analysis of the fuse, the circuit was analyzed to assess the possible overuse of the fuse. This was done because the failure rate is beyond the infant mortality and before the manufacturers’ end of life prediction leading to a reliability concern over the fuse. Whether this is a true fuse issue or a design issue, this is the first step in resolving the matter.
Gideon received several Vishay SS26 Schottky rectifiers for failure analysis. It was thought something within the manufacturing process caused the devices to have a premature end of life in what would be considered a non-stressful application.
The Schottky diode is what is called a majority carrier device. It has advantages in terms of speed because it does not rely on holes or electrons recombining when they enter the opposite type of region as in the case of a conventional diode.
Gideon Analytical Laboratories received several screws to identify whether or not they were the source of carbon disulfide and sulfur dioxide, which were attacking some Buna-N O-rings. O-rings are a mechanical gasket in the shape of a torus; it is a loop of elastomer with a round cross-section, designed to be seated in a groove and compressed during assembly between two or more parts, creating a seal at the interface. The O-ring may be used in static applications or in dynamic applications where there is relative motion between the parts and the O-ring.
Gideon Analytical Laboratories received a printed circuit board (PCB) with suspected failing multi-layered ceramic capacitors (MLCC). Multilayer ceramic capacitors are fixed value capacitors in which ceramic the material acting as the dielectric. It is made up of two or more alternating layers of ceramic and a metal layer acting as the electrodes. There are various types of materials that could function as the dielectric in a capacitor, for example, glass, porcelain, paper, or mica.
Gideon Analytical Laboratories received two valves with failed printed circuit boards (PCBs) and corrosion inside the housing. The goal was to determine what the corrosion was and why the PCB failed. A printed circuit board mechanically supports and electrically connects electronic components using conductive trace lines, pads and other features etched from copper sheets laminated onto a non-conductive substrate. The boards are made from glass reinforced plastic with copper tracks in the place of wires.
Gideon Analytical Laboratories received 8Murata Ps DC-DC converters (pn 8600118) with suspected MOSFET failures. A DC-DC converter is an electronic circuit or electromechanical device that converts a source of direct current (DC) from one voltage level to another. It is a type of electric power converter. Power levels range from very low (small batteries) to very high (high-voltage power transmission). The DC to DC converters MOSFET is a type of field-effect transistor (FET).
Gideon Analytical Laboratories received two 3-phase inductor cards to be analyzed. Three Phase power is a three wire Alternating Current (AC) power circuit. Most US commercial buildings use a3 Phase 4 Wire 208Y/120V power arrangement because of its power density and flexibility.Compared to single phase, a 3phase power arrangement provides 1.732 (the square root of 3) times more power with the same current and provides (7) power circuits. An inductor is a passive two-terminal electrical component that stores electrical energy in a magnetic field when an electric current is flowing through it.
Gideon Analytical Laboratories received two PCB assemblies upon which were several failing Vishay CRCW1210-HP-e3 surface mount (SM) resistors. Surface mount technology (SMT) is a method for producing electronic circuits in which the components are mounted or placed directly onto the surface of printed circuit boards (PCBs). An electronic device so made is called a surface-mount device (SMD). In the industry, it has largely replaced the through-hole technology construction method of fitting components with wire leads into holes in the circuit board.
Gideon Analytical Laboratories received three electrolytic capacitors that were failing in the field. A capacitor stores electrical energy. They have two terminals separated by some type of insulating material, known as a dielectric. Usually, these dialectics are metal plates and the dielectric is made of materials like ceramics, mylar, or glass. Electrolytic capacitors are a type of capacitor that uses an electrolyte as one of its plates to achieve a larger capacitance per unit volume.
Gideon Analytical Laboratories received several electronic metal-halide (MH) ballast black semiconductor diode, but it also permits current to flow in the reverse direction when its “Zener voltage” is reached. The goal was to expose the circuitry and reverse engineer the cause of failure of the three components that were failing at a high rate.
Failure analysis ensued. First, the zener diodes and fuses were exposed and potting material removed so that the circuitry was revealed.
The Lambda KPSA10-15 is a self-contained, offline power supply capable of supply 15Volts DC at 1 Ampere from a universal input of 120VAC ~ 240VAC, 50/60Hz. It is designed for PCB mounting as a module and is passively cooled. Several of these power supplies failed in the field in 2-2.5 years. There was no sign of damage or environmental contamination on the PCB. All arrived DOA. The component selection was mediocre except for the electrolytic capacitors, which were chosen wisely.
Gideon Analytical Laboratories received two transformers from the same manufacturing vintage; one was failed and the other was unused. The transformer is an E-I configuration with a 120v input and 13.45 V output on the secondary. A transformer is an electrical device that transfers electrical energy between two or more circuits through electromagnetic induction. Electromagnetic induction produces an electromotive force within a conductor which is exposed to time-varying magnetic fields. Transformers are used to increase or decrease the alternating voltages in electric power applications.
The RS2042 is a low startup current, current mode PWM controller with Green-Power & burst-mode power-saving operation. It has integrated functions such as the leading-edge blanking of the current sensing, internal slope compensation, low external component counts, and easily fits in with AC/DC power applications. The Green-Power function provides off-time modulation to linearly decrease the switching frequency under light-load conditions. And under zero-load conditions, the power supply enters burst-mode to further reduce power consumption by shutting off PWM output.
Gideon Analytical Laboratories received several lighting switches that were found to remain open even while the switch was closed. A light switch is most commonly used to operate electric lights, permanently connected equipment, or electrical outlets. Portable lamps such as table lamps will have a light switch mounted on the socket, base, or in-line with the cord. Manually operated on/off switches may be substituted by remote control switches, or light dimmers that allow controlling the brightness of lamps as well as turning them on or off.
Gideon Analytical Laboratories received several ball grid arrays (BGAs) to specifically look for any shorts, opens, cracks, or contamination issues that were preventing its operation. Radiography analysis was requested.
A BGA is a type of surface-mount packaging (a chip carrier) used for integrated circuits. They come in two basic types: plastic ball grid arrays (PBGAs) and ceramic ball grid arrays (CBGAs). BGA packages are used to permanently mount devices such as microprocessors.
Gideon Analytical Laboratories received four Spectrum Control Pi filters N49927 Bus A (capacitor components FL1, FL2, FL3, and FL4). Capacitor-input filters (also known as Pi filters) are a type of electronic filter used to remove unwanted frequencies from a signal. Pi filters are primarily constructed of two capacitors and an inductor. They are used in situations where the ripple of a signal or the AC and DC currents within the signal are found to interfere with each other.
Gideon Analytical Laboratories received one failed multilayer ceramic capacitor (MLCC) on a printed circuit board (PCB). Multilayer ceramic capacitors are fixed value capacitors in which ceramic the material acting as the dielectric. It is made up of two or more alternating layers of ceramic and a metal layer acting as the electrodes. There are various types of materials that could function as the dielectric in a capacitor, for example, glass, porcelain, paper, or mica.
Gideon Analytical Laboratories received a power supply with several bulging capacitors on the motherboard. A power supply is an electronic device that supplies electric energy to an electrical load. The primary function of a power supply is to convert one form of electrical energy to another and, as a result, power supplies are sometimes referred to as electric power converters. Some power supplies are discrete, stand-alone devices, whereas others are built into larger devices along with their loads.
Gideon Analytical Laboratories received two Fairchild transient voltage suppressors (TVS) SMBJ5V0CA. Both diodes were identified as having failed.Transient Voltage Suppressors (TVS’s) are devices used to protect vulnerable circuits from electrical overstress such as that caused by electrostatic discharge, inductive load switching, and induced lightning. Within the TVS, damaging voltage spikes are limited by clamping or avalanche action of a rugged silicon pn junction which reduces the amplitude of the transient to a nondestructive level.
Gideon Analytical Laboratories received two failed AUIRF7648M2 MOSFETs. These are rather new on the market and specifically designed for the automotive industry. Typically, when a MOSFET fails, all terminals short. It is the failure analyst's job to discover how the MOSFET failed in the application by combining the schematics, clues found in the failure analysis, and clues found on the PCB to give a complete picture to help resolve the client's problem.
Gideon Analytical Laboratories received two 144A9111 pulse transformers with the secondary wiring shorting. Transformers are devices that transfer electric energy from one circuit to another, usually with a change in voltage. Pulse transformers are transformers optimized for transmitting rectangular electrical pulses. Ideally, pulse transformer designers try to minimize voltage droop, rise time, and pulse distortion. Small versions called signal types are used in digital logic and telecommunications circuits, often for matching logic drivers to transmission lines.
Gideon Analytical Laboratories, Inc. received on Vishay ES2D rectifier on a PCB. The initial condition and observation were that the diode had a conformal coating on a small circuit board in which when tested on a curve tracer had excessive leakage current across the junction and caused the PCB to fail in the application.
Rectifiers are primarily used for conducting in one direction and blocking in the other. The Vishay ES2D is an ultra-fast rectifier, which means the reverse recovery time should be less than 100 ns.
Gideon Analytical Laboratories received one 2N3700 transistor for failure analysis. A new 2N3700 transistor was also received for comparison. A transistor is a semiconductor device used to amplify and switch electronic signals and electrical power. It is composed of semiconductor material with at least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistor's terminals changes the current through another pair of terminals.
Gideon Analytical Laboratories, Inc. received Atmel AT91SAM9260 based Embedded MPU; it is a 180 MHz ARM926EJ-S ARM Thumb Processor. The SAM9260 is based on the integration of an ARM926EJ-S processor with fast ROM and RAM memories and a wide range of peripherals. It embeds an Ethernet MAC, one USB Device Port, and a USB Host controller. It also integrates several standard peripherals, such as the USART, SPI, TWI, Timer Counters, Synchronous Serial Controller, ADC, and MultiMedia Card Interface.
Gideon Analytical Laboratories received several rectifier assembly rotors for failure analysis. A rectifier is an electrical device that converts alternating current (AC), which periodically reverses direction, to direct current (DC), which flows in only one direction. The simplest kind of rectifier circuit is the half-wave rectifier. It only allows one half of an AC waveform to pass through to the load. Rectifiers are used as components of power supplies and as detectors of radio signals.
Gideon Analytical Laboratories received a JanTXV1N821 Zener diode for electronic failure analysis. A diode is a two-terminal electronic component with asymmetric conductance; it has low (ideally zero) resistance to current in one direction and high (ideally infinite) resistance in the other. A semiconductor diode is the most common type of diode; it is a crystalline piece of semiconductor material with a p–n junction connected to two electrical terminals. A Zener diode is a diode which allows current to flow in the forward direction in the same manner as an ideal diode but also permits it to flow in the reverse direction when the voltage is above a certain value, known as the breakdown voltage.
Gideon Analytical Laboratories received four National LM5111-1m dual 5A compound gate drivers. There were two bad devices and two good ones for comparison. A gate driver is a power amplifier that accepts a low-power input from a controller IC and produces a high current drive input for the gate of a high-power transistor. They consist of a level shifter in combination with an amplifier. They can power IGBTs and MOSFETs. They can help control electronics that need higher power than the PWM signals can generate.
Gideon Analytical Laboratories received an RNC70H1963FS resistor for electronic failure analysis. A resistor is a passive two-terminal electrical component that implements electrical resistance as a circuit element. Resistors act to reduce current flow, and, at the same time, act to lower voltage levels within circuits. They are typically constructed of metal wire or carbon and engineered to maintain a stable resistance value over a wide range of environmental conditions. Resistors are rated both in terms of their resistance (ohms) and their ability to dissipate heat energy (watts).
Gideon Analytical Laboratories received two integrated circuits for failure analysis. Integrated circuits (ICs) are an assembly of electronic components, fabricated as a single unit, in which miniaturized active devices (like transistors and diodes) and passive devices (like capacitors and resistors) and their interconnections are built upon a thin substrate of semiconductor material. One was a Texas Instruments 5962-9861201QXA and the other was a Vishay 5962-9562301Q3A. The Texas Instruments 5962-9861201QXA was a DSP fixed-point 16-Bit 40MHz 20MIPS 132-Pin CFPAK.
Gideon Analytical Laboratories received one linear microcircuit modular hybrid FK23009 for electronic failure analysis. A hybrid integrated circuit (HIC) is a miniaturized electronic circuit constructed of individual devices, such as semiconductors and passive components like resistors or inductors, and typically encapsulated in epoxy. The hybrid microcircuit is used in military and communications applications and is excellent for creating custom analog circuits, such as amplifiers and modulators. Thick film technology is often used as the interconnecting medium for hybrid integrated circuits.
Gideon Analytical Laboratories received three 1210 Multi-Layer Ceramic Capacitors (MLCC) for analysis. Multilayer ceramic capacitors are fixed value capacitors in which ceramic the material acting as the dielectric. It is made up of two or more alternating layers of ceramic and a metal layer acting as the electrodes. There are various types of materials that could function as the dielectric in a capacitor, for example, glass, porcelain, paper, or mica. The MLCCs were from a Time Hub printed circuit board (PCB).
Gideon Analytical Laboratories received a failed Microsemi DZ771215A 10 watt diode for failure analysis. Two working devices were provided for comparison. A diode is an electric device that has two electrodes (anode and cathode) and that only allows current to flow in one direction, resisting current in the other direction. Diodes are used copiously as rectifiers, which convert alternating current (AC) to direct current (DC) to change the amplitude of the signal in proportion to its voltage in the circuit.
Gideon Analytical Laboratories received one MLCC on a DC input noise filter PCB on which to perform failure analysis. MLCCs (Multi-Layered Ceramic Capacitors) are extremely ubiquitous in the electronics field; it was estimated that around 1000 billion are produced per year. The MLCC has severe thermal damage but was still intact to the pads via the termination solder connections.
Analytical services were provided. The MLCC could not be cut from the PCB and the PCB could not be cut because of the fragile nature of the condition.
Gideon Analytical Laboratories received several Tusonix Pi filters that were failing in the field. Capacitor-input filters (also known as Pi filters) are a type of electronic filter used to remove unwanted frequencies from a signal. Pi filters are primarily constructed of two capacitors and an inductor and are used in situations where the ripple of a signal or the AC and DC currents within the signal are found to interfere with each other.
" Gideon Analytical Laboratories received four National Semiconductor LM5111-1M dual 5A compound gate drivers. A gate driver is a power amplifier that accepts low-power input from a controller integrated circuit and produces a high-current drive input for the gate of a high power transistor. These LM5111 Dual Gate drivers have high peak output current and efficiency. Each of the compound output driver stage includes MOS and bipolar transistors operating in parallel that together sink more than 5A peak from capacitive loads.
Gideon Analytical Laboratories received one MLCC (Multi-Layer Ceramic Capacitor) with a reported short. Ceramic capacitors are the most produced and used capacitors in electronic equipment. An MLCC consists of a number of individual capacitors stacked together in parallel and contacted via the terminal surfaces. Every MLCC basically consists of a ceramic dielectric, a metalized electrode, and connecting terminals. MLCCs can range in capacitance and voltage rating. Many times they serve to function as devices to reduce electrical noise and provide stability in an operating system.
Gideon Analytical Laboratories received several photodiodes to examine for possible contamination. A diode is a two-terminal electronic component with asymmetric conductance. It has low resistance to current flow in one direction, and high resistance in the other direction. There are various kinds of diodes, including vacuum tube diodes and solid state diodes. The most used and ubiquitous diode is the semiconductor. A photodiode is a type of device capable of converting light into either current or voltage.
Gideon Analytical Laboratories received three PTE43-31-C-RA power supplies, two were failed and the other was a working device for comparison. Power supplies are devices that supply electrical power to an electrical load. Some power supplies convert alternating current (AC) to direct current (DC) for use in a variety of electronics. Typically, a computer needs a power supply that will convert 120 Volt AC power oscillating at 60 Hertz (Hz). Power supplies are vital to most electronic endeavors, like electrical components in machines, process automation, or for power generation.
Gideon Analytical Laboratories received several plated steel parts, including coupons, hinges, and shoulder nuts. The goal was to determine if these parts were RoHS compliant. RoHS is short for Directive on the restriction of the use of certain hazardous substances in electrical and electronic equipment; it was initially created by the European Union in February of 2003. To be RoHS compliant, devices have to be free from the following hazardous substances: Lead, Cadmium, Mercury, Hexavalent chromium, Polybrominated biphenyls, and Polybrominated diphenyl ether.
Gideon Analytical Labs received four Fairchild 74OL6000 field failed Optocouplers along with three good (virgin green dot) devices in which a comparison could be done. The LSTTL input compatibility is provided by an input integrated circuit, with industry standard logic levels. This input ampliﬁer IC switches a temperature compensated current source driving a high speed 850 nm AlGaAs LED emitter. This integration scheme eliminates CTR degradation over time and temperature. The emitter is optically coupled to an integrated photodetector/high-gain, high-speed output ampliﬁer IC.
Gideon Analytical Laboratories received a single failed Spectrum Control Pi filter on which to perform failure analysis. Capacitor-input filters (also known as Pi filters) are a type of electronic filter used to remove unwanted frequencies from a signal. They are called “Pi” filters because of their resemblance to the Greek letter “Pi”. Pi filters are primarily constructed of two capacitors and an inductor and are used in situations where the ripple of a signal or the AC and DC currents within the signal are found to interfere with each other.
Gideon Analytical Labs received one failed relay with one good one for comparison. The failed relay was intermittent @ 2 KHz.
A reed relay is a switch that uses an electromagnet to control the turning off or on within a circuit. The contacts are of magnetic material and the electromagnet acts directly on them without requiring an armature to move them. Sealed in a long, narrow glass tube, the contacts are protected from corrosion and are usually plated with silver, which has very low resistivity but is prone to corrosion when exposed, rather than corrosion-resistant but more resistive gold as used in the exposed contacts of high-quality relays.
Gideon Analytical Labs received two failed RV4140A ground fault interrupter controllers. The devices had far different impedance values than a new one did on several of the input pins. The RV4140A is a low power controller for AC outlet appliance leakage circuit interrupters. These devices detect hazardous current paths to ground such as an appliance falling into the water. The interrupter then opens circuits line before a harmful or lethal shock occurs.
Gideon Analytical Labs received two AD73311L CMOS general purpose analog front end processors. Each device had external thermal damage to the package and solder leads. The intent was to determine whether the failures were thermally or EOS induced. The AD73311L is a front-end processor for applications such as speech and telephony. It has a 16-bit A/D conversion channel and a 16-bit D/A conversion channel. Each channel provides 70 dB signal-to-noise ratio over the voice band signal bandwidth.
Gideon Analytical Labs received two failed RV4141AM ground fault interrupter controllers. The devices had far different impedance values than a new one did on several of the input pins. The RV4141A is a low power controller for AC outlet appliance leakage circuit interrupters. These devices detect hazardous current paths to ground such as an appliance falling into the water. The interrupter then opens the circuit line before a harmful or lethal shock occurs.
Gideon Analytical Laboratories performed failure analysis on several IXYSIGBT IXGH32N60B transistors, encased in TO-247 packages. These transistors are 60 amp 600V 2.3 Rds 200W. The concern was that the devices were not functioning as 600V but topped out at 480V in the application. After failure analysis was performed on the transistors, the company requested that Gideon Analytical Laboratories administer passivation integrity tests on the two good IXYSIGBT IXGH32N60B transistors.
The transistors were prepared for passivation integrity testing.
Gideon Analytical Laboratories received several liquid-crystal displays (LCDs) that had fading issues; there were five failing LCDs and a good LCD for comparison. An LCD is a flat panel display, electronic visual display, or video display that uses the light modulating properties of liquid crystals. LCDs are extremely common in electronic devices such as laptops, digital clocks, and watches, pocket calculators, microwave ovens, or CD players. LCDs are also used in televisions and produce a sharp and vivid image.
Gideon Analytical Laboratories received three sample NEC 104PW161 power inverter boards for failure analysis. A power inverter is designed to convert direct current (DC) to alternating current (AC). Inverters are used to operate all types of electrical equipment that uses batteries. DC current is what batteries store, but most electrical devices need AC current. These NEC104PW161 inverters had an output voltage of 520V and an output current of 5.5mA. The goal was to determine why they were failing.
Gideon Analytical Laboratories received two surface mount (SM) tantalum capacitors that had internal resistive shorts. Capacitors are passive, two-terminal electrical components used to store energy. They vary in construction, but all have at least two electrical conductors that are separated by an insulator, known as a dielectric. Tantalum capacitors are a type of electrolytic capacitor, which are ubiquitous in electronic circuits. Tantalum capacitors have a high capacitance per volume and weight and are more expensive than any other commonly used capacitor.
Gideon Analytical Laboratories received two ICM7555 CMOS RC timers. Each device was pulling down the output.
The ICM7556 is a CMOS RC timer that provides a stable controller capable of producing accurate time delays or frequencies. The ICM7556 is a dual ICM7555, with the two timers operating independently of each other, sharing only V+ and GND. In the one-shot mode, the pulse width of each circuit is precisely controlled by one external resistor and capacitor.
Gideon Analytical Laboratories received one failed surface mount device (SMD) 200 ECSH quartz crystal oscillator and a good SMD 200 ECSH for comparison. A crystal oscillator uses the mechanical resonance of a vibrating crystal of piezoelectric material to create an electrical signal with a very precise frequency, such as a quartz crystal. This frequency is commonly used to keep track of time, to provide a stable and repeatable clock signal for digital ICs, and to stabilize frequencies.
Gideon Analytical Labs received three failed Kapton based flex circuits with opens in the trace lines. The origin of the open was not known. The opens in the trace lines were traced down on the Kapton to several eyelets where contact was supposed to be made.
No areas were distinguished and no anomalies were found suggesting a trace copper foil problem on any of the circuits received. A cross-section of the above trace line and eyelet demonstrates the trace line (the line in the middle) either has been dislodged from the barrel or was never connected.
Gideon Analytical Laboratories received four 220 picofarad AVX capacitors for failure analysis. There are a variety of capacitors, including ceramic, aluminum, film, and tantalum, but all serve the same purpose, which is to store electrical charge. They are passive electrical components with at least two electrical conductors separated by an insulator (dielectric). The four220 picofarad AVX capacitors were giving low resistance readings.
Failure analysis ensued. The four 220 picofarad AVX capacitors were inspected for mechanical cracks, which would propagate upon voltage; no cracks were found on the external ceramic.
Gideon Analytical Laboratories received eighteen digital signal processors (DSPs) for failure analysis. A DSP is a microprocessor architecturally designed to mathematically modify or improve a signal. DSPs are used in a variety of applications, including audio and speech signal processing or and sonar and radar signal processing. The goal in digital signal processing is to convert real-world analog signals into digital signals. Gideon Analytical Laboratories performed failure analysis on the DSPs.
Gideon Analytical Laboratories received two semi-operational LM386 operational amplifiers for failure analysis. An operational amplifier (op-amp) is a DC-coupled high-gain electronic voltage amplifier with a differential input and, usually, a single-ended output. Op-amps are linear devices that have all the properties required for DC amplification and are used in signal conditioning, filtering, or to perform a variety of mathematical operations. The op-amps received were reported to have quiescent current 2 to 3 times the normal value.
Gideon Analytical Laboratories received six pulse transformers, three of which were failures, three of which were reliable. The objective was to determine the cause of the failures and inspect the unused transformers for anything that could contribute to the cause of failures. Transformers are devices that transfer electric energy from one circuit to another, usually with a change in voltage. Pulse transformers are transformers optimized for transmitting rectangular electrical pulses. Ideally, pulse transformer designers try to minimize voltage droop, rise time, and pulse distortion.
Gideon Analytical Laboratories received several amplifier units were supplied to ascertain the difference between a new vintage resistor, which failed, and the older one, which functioned normally. A resistor is a passive electrical component that enacts electrical resistance in a circuit. These resistors were measured at 22 ohms.
Failure analysis was performed on the resistors. It was not known if the resistors were from the same vendor or whether the power dissipation of the thick film was the same.
Gideon Analytical Laboratories received an Areovox Z26P6045M21 45uF 600V capacitor for failure analysis. Capacitors are passive two-terminal electrical components used to store electricity in an electric field. Inside most capacitors, there are two metal plates separated by a non-conducting substance (dielectric). Filter capacitors are used for filtering undesirable frequencies and removing voltage or signal spikes in electronic circuits. They are utilized in a variety of applications. Gideon Analytical Laboratories performed failure analysis the Areovox Z26P6045M21 45uF 600V capacitor.
Gideon Analytical Laboratories received several contaminated lead screw assemblies. Also received were three insulin samples, one grease sample, and several new parts making up the lead screw assembly. Lead screws are designed to translate turning/rotary motion into linear motion. The contamination on the shaft of the assembly was primarily concentrated between the bearing and the ball seal. The goal was to identify and determine the cause of the contamination.
Gideon Analytical Laboratories primarily used FTIR and SEM-EDS analysis for diagnostics.
Gideon Analytical Laboratories received metallurgical corrosion failures from lamp sockets. The materials and the insulation protection was compared to distinguish the difference between the two lamp sockets. The lamp sockets were overheating and melting the wire insulation in the application. These sockets are a type of bi-pin lamp fitting. Bi-pin lamp fittings are for use in incandescent (especially halogen) and some fluorescent lights. MR16 refers to the lamp construction and overall diameter at its largest circumference.
Gideon Analytical Laboratories received several dual N-channel SO-9 Vishay Siliconix MOSFETs. MOSFETs are transistors used for amplifying or switching electronic signals. The MOSFET is the most common transistor in both digital and analog circuits, used in many scenarios where voltage conversion is necessary. These dual N-channel SO-9 Vishay Siliconix Si4980DY MOSFETs were received for component evaluation and environmental testing in a variety of conditions to determine any noticeable flaws or anomalies with the package, die, or electrical parameters.
Gideon Analytical Laboratories received two failed terminal block electrical connectors from two different installation sites. These terminal connectors connect two or more wires to a single connection point, providing a convenient method of connecting electrical wiring without splicing or physically joining the ends. The two connectors were identical in construction, and both appeared burned out from overpower.
The connector was cross-sectioned and SEM-EDS analysis performed. The screws in the terminal block connector typically are tin plated copper clad iron.
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.
This filter is used in a water filter system for water consumption. The filters were plugging up rather fast with the pink material shown in the photograph below.
Since these problem types are unknown, one must choose the appropriate analysis method for material identification. Methods used are Fourier transform infrared spectroscopy (FTIR), X-Ray Diffraction (XRD) and Gas Chromatography-mass Spectrometry (GCMS)) since the filters were designed to filter out organics and inorganics.
This is a picture of a copper wire that used to have tin plating and nickel plated pad. The wire was running 120V at 60Hz. The connection was placed in a non-hermetical container where chlorides in the atmosphere were high. Over time the chlorides attacked the exposed copper and undermined the tin plating on the copper wires. The resistance in the wire increased, the copper arced due to this increased resistance and the socket assembly failure to corrosion.
This a micrograph of copper oxide deposits on nickel plating. The copper oxide is inhibiting the electrical conduction of a 120V light on terminals of a light bulb. This is an environmental failure stemming from the fact that the exposed copper on another part of this circuit, deposited copper oxide by arching, and this, in turn, caused an eventual loss in conduction to the bulb.
This arcing happens when low-level contaminants are present and concentrate over time.
The analysis was performed on ten failed microwave capacitors. They were Samwha vintage 2100VAC .65uF with 3 percent tolerance with a maximum temperature rating of 85oC. All the capacitors were tested for shorts or opens. The resistance of the integrated resistor was measured also. None of the integrated resistors failed. They all varied from 9.75-M ohms to 10.85M ohms. Many of the capacitors saw considerable heat. This was evident by the bulging deformed metal can housing.
Gideon Analytical Laboratories received two integrated load switches and two small signal diodes for analysis. The integrated load switches are particularly suited for compact power management in portable electronic equipment where 2.5V to 8V input and 2.8A output current capability are needed. They have an operating voltage range 1.2V-20.V. The signal diodes are non-linear semiconductor devices generally used in electronic circuits, where small currents or high frequencies are involved such as in radio, television and digital logic circuits.
Gideon Analytical Laboratories received an industrial scale to analyze possible manufacturing defects and potential problems that affect “calibration” weight for long-term reliability. Many of these scales are used in heavy industry or veterinary applications. These scales also come in a variety of categories for different uses, including platform, drum, cylinder, and crane, among others.
There was some residual contamination that sat on top of the strain gauge but under the conformal coating, which can be seen in the picture at the top left.
Gideon Analytical Laboratories received several SVAA-3V25 relays for failure analysis. These solid state relays have a control voltage range between 100 VAC and 280 VAC, a load voltage rating of 330 V, and a load current rating of 25 A. Solid state relays are ideal for industrial and commercial ovens, injection molding machines, and induction furnaces, and many other applications. The goal was to find the cause of the failures.
This picture shows the entire printed circuit board with epoxy encapsulated. This type of encapsulation coating is great for automotive electronic applications where vibration and debris can be minimized, but it will prevent cooling efficiency since the component surface area will not radiate heat by convection to ambient air, and it can prevent simple follow-up rework, probing, debug, and failure analysis.
Correctly left out of the epoxy area are connectors, terminal screws, and any power devices.
Gideon Analytical Laboratories performed failure analysis on several Bias BPS2-07001 failed power supplies. Several good units were submitted for comparison. These Bias BPS2-07001 are linear and switching power supplies 2W 14V, 5V DUAL 85-265V Std Temp and are ROHS compliant. They provide up to one-half, one, or two watts of output power (BPS0.5, BPS1, and BPS2) at 8 or 14 VDC (Vo) and an optional 3.3 or 5 VDC (Vr) output to power standby functions such as clocks, microprocessors, remote control sensors, and more.
Gideon Analytical Laboratories received a PCB that had a fire in one section of the board. These PCBs can provide high-performance 10G visibility for network monitoring tools in all parts of a fiber network. They feature to 24 SFP+ ports supporting 10G and 1G Ethernet (10GbE and 1GbE) and up to four RJ-45 copper Ethernet ports. The objective was to find the cause of the fire on the board, in an already established product line.
Gideon Analytical Laboratories received three central air conditioner hubs. These air conditioners can are built for commercial or residential use. Depending on their SEER ratings, they run between 66dB and 72dB and use Puron refrigerant. The hubs had corrosion on the PCB and had the appearance that some liquid flowing between the insulation and wire leading into the cavity. The goal was to discover the identity and cause of the corrosion.
Gideon Analytical Labs received several printed circuit boards (PCB) with fire damage on one and electrical overstress on the LTC4258CGW module when received. One good unit was provided for comparison. The objective was to find the cause and access the risk to the customer.
The LTC4258 can operate autonomously or be controlled by an I2C serial interface. Fault conditions are optionally signaled with the INT pin to eliminate software polling. External power MOSFETs, current sense resistors and diodes allow easy scaling of current and power dissipation levels and provide protection against voltage and current spikes and ESD events.
Gideon Analytical Laboratories received one failed optocoupler, along with two optocouplers for comparison. As a type of isolator favored by manufacturers, photocouplers
serve as noise protectors in many electronic devices. This optocoupler has a minimum isolation voltage of 5300 Vrms, a typical input voltage of 1.16 V, and a peak output voltage of 600V. The goal was to identify the cause of the failure.
The optocoupler was electrically tested. The input functioned normally with VF 1.
Gideon Analytical Labs received several PCB that opened up on several of the I/O metal dome pads.
The three black circles are the time, status, and menu pads. The metal domes came out when the two switches were separated. These buttons are connected to an output. The insulator cavity (the black spots) provides space for the metal dome. The metal dome makes contact when pushed from the top switch circuitry to the bottom switch shown later.
Gideon Analytical Laboratories received a single capacitor for failure analysis. The capacitor had a capacitance of 22µF, a voltage rating of 400 V, was ROHS compliant and had a vented bottom and the wound was exposed. The goal was to determine the cause of the failure.
The capacitor sleeve was not cracked and bulging was not apparent. This usually indicates the failure occurred during a minor period from onset of the pressure build up within the can.
Gideon Analytical Laboratories received a single MA COM MAAPSS0096 1 watt power amplifier for failure analysis. The device was thought to have some impedance issues.
The device was still attached to PCB on arrival, as displayed in the picture at the top left. The device was removed from the PCB and tested to find any indication of the condition of the internal circuitry. The MAAPSS0113 is a three stage power amplifier designed for Digitally Enhanced Cordless Telephone applications.
Gideon Analytical Labs received two 0805 MLCC capacitors mounted on daughter boards and several good capacitors for comparison. One capacitor mounted on a PCB had multiple cracks.
The pictures supplied indicated several horizontal cracks. The capacitor was cleaned and cut from the remainder of the PCB and mounted for horizontal to the PCB.
After analysis the conclusion was a combined affect of terminal fracturing and poor soldering wetting lead to over heating which in turn caused thermal cracks that lead to the EOS.
Gideon Analytical Laboratories received a PCB with possible failed capacitors in several positions. PCBs are used to mechanically support and electrically connect electronic components. They are used in almost every all but the simplest electronic devices, from GPS systems to laptops, from cell phones to microwave ovens. Several MLCC capacitors on this PCB had failed, and the goal of Gideon Analytical Laboratories was to diagnose the cause of the failure.
Gideon Analytical Laboratories performed failure analysis on one opened splitter module LPF-200 PCB encapsulated in the black urethane potting material and housed in plastic. The PCB was burnt in one spot, and in that spot, a cavity existed under the carbonized epoxy of the PCB adjacent to the PTH. The trace line had a number of craters strongly suggesting an “electromigration” of copper. In order for electromigration to occur with copper a voltage, an acid and medium (moisture) must be present.
Gideon Analytical Laboratories performed failure analysis on several SM Syfer SM MLC Capacitors (also known as MLCC failures). The goal was to determine the root cause of these failures. Pictured on top left is the failed capacitor; it had an 11.5 Kohm resistance short.
The capacitors were cross sectioned. All cross sections of the new Syfer were in excellent quality. No voids, knit cracks, delamination, blow holes, or contamination was found.
Gideon Analytical Laboratories received electrolytic capacitors for chloride analysis according to a prior analysis technique for determining the presence of chloride. The chloride analysis technique was developed because chlorine is a known catalytic corrosive element on aluminum.
The analysis was performed using an SEM-EDS system giving elemental analysis in relation to the intensity of the element at a specific wavelength or energy level (Kev). Since Kev (energy levels) for specific elements do not change, these are used to identify the elements in the sample.
Gideon Analytical Laboratories received 100 capacitors and directed to analyze them via cross-sectional analysis. Capacitors store charges and frequently appear on PCBs. There are many types of capacitors; electrolytic capacitors are tantalum capacitors are fairly common. The goal was to discover any abnormalities or determine if there were no abnormalities.
Each capacitor was cross-sectioned and observed 15 to 20 times under 40-72x magnification during the sectioning process. At some point during the cross-sectioning process, pictures were taken to depict the internal quality of the ceramic structure and any cracks (mechanical, knit, Kirkendall voiding or other defects) that may be present.
Gideon Analytical Laboratories received several shorted PX6A07 silicon rectifiers for failure analysis. Two good devices were provided for reference and comparison. A semiconductor diode is a crystalline piece of semiconductor material with a p-n junction connected to two electrical terminals. It conducts in the forward direction and is blocked in the reverse direction.
The good diodes were tested for conformance to the manufacturer’s specification. The good diodes performed per specification or exceeded electrical parameters listed.
This is a 6 amp plastic encapsulated silicon rectifier (PX6A07). Several of these high current diodes failed in the application.
The arrow points to the spot of one of the failures on one device after the epoxy and copper lead frame was removed.
The picture on the right is the anode. In the middle is the copper contact and the ring is actually the contact via solder to the P+ region of the die.
This is a class 2 inspection of a printed circuit board (PCB) using the IPC-A-610 Rev E. There is a bubble between the two solder joints of the opposite polarity battery terminals.
These enclosed mini-environments are known repositories for ions which will conduct when a voltage is applied. The leakage current drain is often dependent on the amount of moisture present in the atmosphere since the inside bubble environment will equilibrate with the surrounding atmosphere.
This vendor from China was in the process of qualification. There are solder dross and conductive flux underneath the conformal coating. Solder dross is highly conductive and flux will activate as an ionic conductor across leads, pads, terminals, etc.
Conformal coatings inhibit the crosstalk and ionic migration across the PCB surface. If, however, these contaminants reside on the board surface, the conformal coating cannot make contact with the solder mask and does not bond properly.
Gideon Analytical Laboratories received two 42-inch cables. One cable labeled with a mark where an intermittent open occurred and the other a new cable for comparison. Radiography cannot reveal any anomalies. Resistive measurements were taken along the wire to determine the location of the high resistance. The polypropylene was removed and several wires were inspected for holes or mechanical damage (kinks, exceeding bend radius, cuts, scoring, etc.) to the outer insulation.
Gideon Analytical Laboratories performed failure analysis on several polyimide flex circuits with corrosion near an IC. As seen in the picture above left, the corrosion appeared as black outgrowth along the trace lines. These flex circuits allow for greater functional capacity and miniaturization while maintaining high reliability through quality and consistency. They can be used in the aerospace, automotive, computer data and processing, and consumer FTIR.
The picture above right is of SEM-EDS spectral analysis showing the corrosion area.
Gideon Analytical Laboratories received three contaminated Buna-N diaphragms and several new ones for reference. These Buna-N diaphragms have a variety of applications, including in submersible level transmitters, actuary assemblies, air operated diaphragm pumps, and manual loading regulators. The goal was to identify the contamination and pinpoint its cause.
Upon examination under a stereo-zoom microscope, it was found that the surface of the sample contains a thick layer of a gel-like material.
Gideon Analytical Laboratories received two printed circuit boards (PCB) with the questionable failure of multilayer ceramic capacitors in the C4 position. Both these capacitors were removed from the PCB and the PCB was inspected for contamination for possible leakage current or electromigration that would account for conduction across the pad lands.
The picture at the top left is the C4. During analysis, no contamination was found on either of the PCBs or on any of the four sides of each capacitor.
Gideon Analytical Laboratories performed failure analysis on several Sky CKC-1C-12VDC 12A/120V relays. These relays have a contact resistance of 100 Mohms and have a surge resistance of 1000V. The devices had a liquid on the inside surface and corrosion on several of the leads. The liquid and corrosion is pictured at the top left.
The drop was analyzed using FTIR. The liquid was thought to have come from the flux residue and, therefore, an organic analysis FTIR is required as opposed to inorganic (XRF).
Gideon Analytical Laboratories performed failure analysis on two printed circuit board assemblies (PCB) with fractured solder joints on the Hall Sensor interconnect. The assemblies were taken apart and the conformal coating was removed to reveal the solder joints of the Hall Sensor. Five out of six of the Hall Sensors were mounted flush against the Valox 457 mounting block.
A Hall Effect Device detects magnetic flux density and is used in both movement and position sensing.
Gideon Analytical Labs performed failure Analysis on a failed RJR26 Bourns Potentiometer. The application failure was noticed when a lower than expected resistance value and, eventually, open in the potentiometer.
A potentiometer (or pot) is a simple electromechanical transducer. It converts rotary or linear motion from the operator into a change of resistance, and this change is used to control the resistance within a circuit. The pot (also known as a rheostat) is essentially a variable wire wound resistor or a carbon or metal film with a swiper.
Gideon Analytical Laboratories received two surface mount T491C155M035AT Kemet tantalum capacitors with internal resistive shorts. These capacitors have standard capacitance tolerances of ±10% and ±20%, with an operational temperature -55°C to +85°C rated voltage and up to +125°C with voltage derating in applications utilizing recommended series resistance. They have low leakage and are ROHS compliant. The goal was to determine the reason for the failure.
There was no damage tothe external plastic encapsulation of the package to indicate mechanical stress, which would weaken the package integrity.
Gideon Analytical Laboratories performed failure analysis on severalIXYS IGBT IXGH32N60B transistors, encased in TO-247 packages. These transistors are 60 amp 600V 2.3 Rds 200W. The concern was that the devices were not functioning as 600V but topped out at 480V in the application.
Displayed in the picture above is a defect near the guard ring. Further analysis revealed there are several metal posts contacting more than likely underlying diffusion for voltage termination.
Gideon Analytical Laboratories performed failure analysis on one Ansul IQ-396X, which was submitted for possible failure due to an electrical surge. These control units have two intelligent signaling line circuits (SLC), 396 intelligent device capacity (198 intelligent detectors and 198 monitors/control modules), four built-in output circuits, up to 64 internal output circuits/relays on optional modules in the unit, 99 programmable zone output relays, and manual sensitivity adjustment.
The CPU 400 unit was dissembled and the entire board and components were inspected under 40x to look for and evidence of EOS (electrical overstress) that may have affected the operation of the unit.
Gideon Analytical Laboratories received a PCB for failure analysis. The board was identified as having a short from the NET trace to the ground. The short measured about 10 ohms. One area of the board was abraded to reduce the thickness of the black solder mask. The board was received like this and we tried to change the refractive index to optically see through the solder mask. This was unsuccessful. The abraded area produces different optical characteristics, which prevent clear optical vision.
Gideon Analytical Laboratories received an Aerovox Z26P6045M21 45uF 600V for failure analysis. No data was given on the capacitor. The capacitor was tested and found open. It did not take a charge when a voltage was applied. The capacitor was also under gas pressure and this gas was carbon dioxide. The top portion of the capacitor after it was removed showed a phenolic insulator used for the registration of the terminal leads.
Gideon Analytical Laboratories performed failure analysis on a cold rolled steel plate that was received with what looked like tape prints, fingerprints, and black oil which all appear to interfere with the plating process.
Using one microliter of methylene chloride (ACS HPLC Grade) the surface of the cold rolled steel was collected in a glass vial. A portion was then evaporate onto a KCL wafer and analyzed on an FTIR to give spectra in the top picture.
Gideon Analytical Laboratories performed failure analysis on ten failed microwave AC capacitors used in microwave applications. The capacitor used as a doubler failed in the circuit by shorting.
The capacitors were Samwha vintage 2100VAC .65uF with 3 percent tolerance with a maximum temperature rating of 85°C. All the capacitors were tested for shorts or opens. The resistance of the integrated resistor (internal and immersed in the dielectric fluid) was measured also.