SMT 101 Quiz Question Title * 1. What concern exists when mixing tin-lead and tin-bismuth solders? Bismuth will not alloy with lead Tin-bismuth-lead can form a low melting point alloy There is no concern The bismuth will precipitate out The lead will precipitate out Question Title * 2. How much copper is in SAC305 solder? 3.0 % 0.3% 3.5% 0.5% None of the above Question Title * 3. Which temperature is closest to SAC305’s melting point? 230C 210C 183C 220C 200C Question Title * 4. What does OSP stand for? Organic solderability preservative Organic solderability protectant Operational soldering procedure Operational soldering process Question Title * 5. What does ENIG stand for? Energizing nitrogen gas Electroless nickel gold Evolving nitrogen inerting gas None of the above Question Title * 6. In solder paste, what is response to pause? When paused, when stirring the viscosity decreases Whether or not the paste viscosity increases when printing is paused Whether or not the paste viscosity decreases when printing is paused When printing is paused the flux separates from the paste and makes a mess Question Title * 7. What is more typical of a solder paste powder diameter: 5 mils 30 microns 25 mils 5 microns Question Title * 8. The formula for aspect ratio (AR) for a stencil aperture is: d/t, where t is the stencil thickness and d is the line width. Assuming the stencil is 5 mils thick, what is the finest line that can be reliably printed? A rule of thumb is the AR should be ≥1.5. 5.5 mils 3.5 mils 7.5 mils 10 mils 4.5 mils Question Title * 9. Assume that component placement is the “gate” in an SMT assembly process line, which has one chip shooter and one flexible placement machine. The chip shooter takes 60 seconds to place its components. While the flexible placer takes 45 seconds. There are some chips being placed by the flexible placer. To improve productivity, what should be done? Nothing, everything is fine Chips should be taken off the flexible placer and put on the chip shooter as chip shooters are best to place chips. Chips should be removed from the chipshooter and placed on the flexible placer to time balance the line The chip shooter is so slow, move all of the components to the flexible placer Question Title * 10. What is a fiducial on a printed wiring board? It shows the PWB manufacturer that the etching process is within specification. It is used to align the PWB to the assembly equipment It is needed as a reference for solder mask It is the most cost effective way to minimize PWB warpage. Question Title * 11. If you would like to participate to win a $25 digital gift card, please leave your contact information. Indium Corporation reserves the right to modify or cancel this promotion, due to system error, fraud, or other unforeseen problems. If you have any questions, please email us at askus@indium.com. Name Email Address Done
