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 Labs performed analysis on several Melexis US2881 Sensors when the designer found shorts on the returned product from the field.
Melexis US2881 sensors are bipolar Hall-effect switches designed in mixed signal CMOS technology. They have a wide voltage operating range from 3.5V to 24V, have high magnetic sensitivity, and a chopper-stabilized amplifier stage, and are suitable for automotive or consumer applications.
Analysis revealed tin crystals (whiskers) spread throughout the top and bottom of the PCB, shorting out the MOSFET as well as the Hall sensor.
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 BZT52B5V6-V Zener diodes with dead shorts. The most common function of a diode is to allow an electric current to pass in one direction (forward direction) while blocking current in the opposite direction (reverse direction). Thus, the diode can be viewed as an electronic version of a check valve with current passing in only one direction and blocked in the opposite direction. This unidirectional behavior is called rectification and allows one to convert alternating current to direct current.
Gideon Analytical Laboratories received a failed SFH 320 optocoupler in a dual S0-8 package for failure analysis. Optocouplers can be used in many applications, including phototransistor, phototriac, or photodarlington outputs, in a range of through-hole and surface-mount package types. Many are digital optocouplers are used in the automotive industry. They come in a variety of AC and DC configurations, have high noise immunity, and are high temp devices. Two functionally good optocouplers were supplied for comparison.
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 two failed photocouplers for failure analysis. These photocouplers feature a high isolation voltage, high-speed switching, and high collector to emitter voltage. They are used in many types of applications, including power supply, telephones, and fax machines. The optocoupler was electrically tested; there was a short on both input diodes. The goal was to determine the cause of this failure.
After curve trace tests were performed, both failed devices were immersed in a low surface tension dye penetrant This is a modified Mil-Std 1014.
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.
