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Flex Plus (Xiamen) Co., Ltd
Flex PCB Manufacturer in China
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What Is a QFN Package?
A QFN (Quad Flat No-Lead) package is one of the most widely adopted SMT integrated circuit packages in modern electronics manufacturing. Its defining characteristic is that it eliminates the traditional extended gull-wing leads found on older packages like QFPs. Instead, a QFN features flat, perimeter pads (lands) located on the bottom surface of the component body. By moving these electrical connections underneath the package, QFN design breaks through the physical limitatio

Flex Plus Tech team
Jul 7


BGA Solder Joint Failure: Understanding Kirkendall Voids and the Nickel Solution
In high-density electronics manufacturing, BGA packaging is everywhere. We rely on it for high-pin-count components like CPUs and GPUs. However, unexpected BGA solder joint failure remains a massive headache. It is still one of the most frustrating reliability bottlenecks in the industry today. A lot of technicians look at these open circuits and blame drop damage. But the true root cause often lies deeper. It traces back to a sub-microscopic metallurgical phenomenon called k

Flex Plus Tech team
Jul 2


Tin Whiskers on Solder Pads
Tin whiskers are one of the most challenging long-term reliability issues in electronics. These microscopic metallic filaments can grow spontaneously from tin-plated surfaces. They may create unexpected electrical shorts months or even years after a product enters service. As the electronics industry moves toward lead-free finishes, tin whisker control has become increasingly important. Especially in flexible printed circuits, rigid-flex PCBs, and high-reliability assemblies.

Flex Plus Tech team
Jun 25


Flexible PCB Quality: Complete Inspection and Reliability Evaluation Guide
Flexible PCB quality directly impacts product reliability, assembly yield, and long-term field performance. A flexible circuit may pass electrical testing. However, hidden defects can still lead to failures during assembly or operation. Common issues include weak copper adhesion, coverlay delamination, plating defects, and poor environmental resistance. Manufacturers use multiple methods to evaluate flexible PCB quality. These methods include visual inspection, dimensional ve

Flex Plus Tech team
Jun 15


FPC hipot testing: Causes of Arc Discharge and Leakage Voltage Failures
FPC hipot testing is one of the most important electrical reliability inspections in flexible PCB manufacturing. While continuity testing verifies that circuits are connected correctly, it does not reveal insulation weaknesses that may lead to electrical failures in actual applications. During hipot testing, manufacturers occasionally encounter arc discharge, leakage voltage, or insulation breakdown. These failures can occur even when the FPC passes all previous electrical in

Flex Plus Tech team
Jun 9


Achieving Mixed Copper Thickness flexible PCB circuits Solutions: 3 Mass-Production Routes That Actually Scale
In advanced flexible printed circuit design, engineers often face a classic physical paradox: a single board must handle high-current power transmission in one area while maintaining extreme dynamic flexibility in another. To solve this, the flexible PCB circuits must feature mixed copper thickness flexible PCB circuits structures—incorporating thick copper (e.g., 2oz) for battery management systems or heavy-duty soldering pads, alongside ultra-thin copper (e.g., 1/3oz) for t

Flex Plus Tech team
Jun 4


FPC Dry Film Etching & Imaging : How to Prevent Open and Short Circuits
The most effective way to prevent open and short circuits during FPC dry film imaging and etching is to implement tightly controlled pre-treatment, anti-wrinkle dry film lamination, calibrated UV exposure, standardized development breakpoints, and low-undercut etching. Targeted process tuning for thin polyimide substrates and ultra-thin copper foil can eliminate over-etching, photoresist residue, light scattering and lamination voids—the four root triggers of mainstream flexi

Flex Plus Tech team
Jun 2


Optimizing Hard Gold Flexible PCB Solderability: Why Plating Thickness Matters for SMT Wetting
In flexible PCB manufacturing, surface finish selection dictates both the mechanical longevity and the surface mount technology yield of the board. For decades, the industry rule of thumb has been straightforward: hard gold (electrolytic Au with Co/Ni alloy hardening agents) is for wear resistance on gold fingers, while soft gold or ENIG is for SMT soldering. However, advanced flexible PCB designs frequently require components to be soldered directly onto or adjacent to hard-

Flex Plus Tech team
May 28


Pre-Tinned Flexible PCB Pads vs Bare Pads in Flexible PCB Manufacturing
In flexible PCB production, one detail that often causes confusion is the difference between pre-tinned flexible PCB pads and bare pads. On the surface, they may look like a simple variation in appearance, but in real manufacturing, they represent two completely different usage scenarios. Understanding this difference helps avoid wrong expectations during assembly and improves communication between FPC manufacturers and customers. What Are Pre-Tinned Flexible PCB Pads? Pre-ti

Flex Plus Tech team
May 21


Conformal Coating for Flexible PCBs
A flexible PCB may pass all electrical tests during production but still develop reliability issues later in actual use. Moisture, condensation, flux residue, dust, oil vapor, and temperature cycling can gradually affect exposed conductive areas. In compact FPC assemblies with fine trace spacing, even small amounts of contamination may eventually lead to corrosion, leakage current, or unstable electrical performance. This is why conformal coating is commonly added after SMT a

Flex Plus Tech team
May 14
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