May30
Conformal Coating: How to Understand and Choose the Right Material

post on May 30, 2024

Conformal Coating: Understanding and Choosing the Right Material

Conformal coating is a protective chemical coating or polymer film applied to printed circuit boards (PCBs) and critical electronic components to protect them from environmental factors such as moisture, dust, chemicals, and temperature extremes.

This coating, typically 25 to 300 µm thick, enhances the product’s resistance to moisture, dirt, dust, and chemical contamination. Additionally, it prevents solder joints and conductors from continuing to corrode by blocking contact with air. By incorporating specific ingredients, conformal coatings can also provide shielding against electromagnetic interference and serve as an insulator.

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Glue/adhesive/epoxy/underfill,     WorkingBear    Views (1,454)     comment (0)
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May23
How to Resolve HIP or HoP Soldering Issues in BGA Solder Balls

post on May 23, 2024

BGA packages  are prone to HIP, also known as HoP defects, during the reflow process, and it is an undeniable fact that the larger the size and the more balls a BGA package has, the more likely HIP is to occur. This double-ball soldering defect, Head in Pillow , is a particularly troublesome engineering problem because neither 2D X-ray inspection nor electrical testing (FVT or ICT), and even sending the product to burn-in (B/I), can detect HIP issues with 100% certainty.

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Quality, SMT, Soldering     WorkingBear    Views (1,326)     comment (0)
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May02
Concept Clarification: IMC Layer Fracture Despite the Formation of Effective Solder Joints

post on May 2, 2024

Concept Clarification: IMC Layer Fracture Despite the Formation of Effective Solder Joints

In this blog, Workingbear has explored the causes and analysis of soldering cracks and electronic component detachment in several articles. It has consistently mentioned that most of the fractures occurring when electronic components detach happen at the Intermetallic Compound (IMC) layer. This indicates that the most vulnerable part of the overall structure, once the component is soldered to the PCB (Printed Circuit Board), is this IMC layer, hence the fractures occurring at this point.

However, nearly all articles also point out that it is essential to form this IMC layer between the solder paste and the component leads, as well as between the solder paste and the metal of the PCB, for effective soldering, ensuring solder joint strength.

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Quality, Reliability, SMT, Soldering     WorkingBear    Views (1,420)     comment (0)
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Apr25
How are decisions made regarding stencil thickness, aperture, and shape? How can solder beads be prevented?

post on April 25, 2024

How are decisions made regarding stencil thickness, aperture, and shape? How can solder beads be prevented?

A user asked: “How is the thickness of the stencil determined? What considerations are there for the shape of the stencil apertures?”

The thickness of the stencil is mainly determined by the amount of solder paste needed for component soldering. Thinner stencils usually mean less solder paste deposited during printing. The amount of solder paste required for each solder joint depends on the components on the printed circuit board (PCB), especially those sensitive to solder volume, such as BGAs with the smallest ball pitch and fine-pitch components. Additionally, smaller components demand higher precision in solder paste printed. Ultimately, the decision also depends on the quality of solder joints after soldering.

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SMT, Soldering     WorkingBear    Views (1,374)     comment (0)

Apr18
Pros and Cons of Selective Soldering Machines

post on April 18, 2024

Pros and Cons of Selective Wave Soldering Machine. The image is sourced from the internet. If there's any infringement, please inform us for removal or cooperation.

Selective soldering machines are a compromise solution in modern PCB Assembly (PCBA)processes. Despite the advancements in surface mount technology (SMT), electronic components still rely on traditional Through-Hole Technology (THT) due to cost or material constraints.

Even though most components on PCBs can be assembled using SMT, some electronic parts still require THT processes. While techniques like Past-In-Hole (PIH) or Pin-In-Paste (PIP) allow through-hole components to be used in SMT assembly or use selective mask wave soldering process, limitations persist due to component technology. As a result, selective soldering machines have emerged.

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Soldering     WorkingBear    Views (1,371)     comment (0)
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