Padget Electronics Senior Smt Engineer Interview Questions, Process, and Tips

SMT (Surface Mount Technology) is a process used in electronics manufacturing to mount electronic components onto the surface of a printed circuit board (PCB).

• SMT involves placing electronic components onto the PCB using solder paste and a pick-and-place machine.

• The solder paste is applied to the PCB using a stencil, and then the components are placed onto the paste.

• The PCB is then heated in a reflow oven, causing the ...read more

Multiple AOI defects can occur due to various reasons and can be resolved by identifying the root cause and taking corrective actions.

• AOI defects can include missing components, wrong polarity, tombstoning, bridging, etc.

• Root causes can be incorrect programming, machine calibration, component placement, solder paste printing, etc.

• Corrective actions can include reprogramming, recalibrating, adjusting placement parameter...read more

Multiple SPI defects can occur due to various reasons, leading to poor quality and reliability of the product.

• SPI defects can be caused by issues with the solder paste, stencil design, or the reflow process.

• To resolve the issue, it is important to identify the root cause and take corrective actions.

• Improving the solder paste quality, optimizing the stencil design, and adjusting the reflow profile can help resolve the i...read more

SPI parameters are defined based on the specific requirements of the PCB and components being used.

• SPI parameters include clock frequency, data format, and signal voltage levels.

• The clock frequency should be set to the maximum frequency supported by the components.

• Data format can be set to either MSB or LSB depending on the component requirements.

• Signal voltage levels should be set to match the voltage levels of the co...read more

To modify stencil, fixture, palets, support block and BGA rework stencil, one needs to follow specific steps.

• Stencil modification requires adjusting the aperture size and shape to improve paste deposition

• Fixture modification involves changing the clamping mechanism to ensure proper alignment

• Palet modification involves adjusting the tooling holes to fit the PCB

• Support block modification requires changing the height to a...read more