To ensure populated printed circuit boards meet quality standards, it’s essential to visually inspect them for flaws and anomalies during assembly. This paper introduces wettable-flank capability with novel immersion Sn plated on lead flank.
What is a wettable QFN? - element14 Community
Oct 19, 2018 · Wettable flanks (WF) are modifications to the exposed terminal ends, which “promote solder wetting for the formation of a solder fillet” that is visible. Using a QFN package with a wettable flank enables optical inspection of the soldering, which can increase reliability, while reducing cost at the same time. Why is this a big deal?
TI’s LM53600-Q1 and LM53601-Q1 automotive DC/DC buck regulators are available in a QFN package that uses a wettable flank process approved by many of the largest automotive OEMs.
Wettable Flank Plated PQFN - Allegro MicroSystems
A standard QFN board layout is used for sidewall plated parts with the addition of extended terminal lands 40 mil (1.00 mm) in length (see Figures 1, 2) and of 31.5 mil (0.80 mm) (refer to Figures 3 and 4). This allows additional solder paste to flow to the terminal wettable flank and form a solder fillet there which can be visually identified.
not only formed between the QFN bottom side and the PCB but also includes the wetting of the QFN flanks. Immersion tin plating offers the possibility to create fully wettable flanks by covering exposed copper at the QFN side walls with a plated tin …
MLF/QFN within the automotive industry has been the innovation of side wettable flanks that provide the capability to inspect the package lead to printed circuit board (PCB) interfaces for reliable solder joints.
US20140357022A1 - A qfn with wettable flank - Google Patents
Quad Flat No Lead (QFN) packages use a leadframe as a substrate onto which one or more integrated circuits (ICs) are attached and subsequently wirebonded to form electrical connections from...
A standard QFN board layout is used for sidewall plated parts with the addition of extended terminal lands 40 mil (1.00 mm) in length (see Figures 1, 2) and of 31.5 mil
Texas Instruments (TI) Quad Flatpack No-lead (QFN) 14/16/20-terminal Pb-free plastic packages meet dimensions specified in JEDEC standard MO-241, allow for board miniaturization, and hold several advantages over traditional SOIC, SSOP, TSSOP, and TVSOP packages.
可润湿侧翼Q F N封装对于汽车应用的价值所在 - 汽车 - 技术文章
Apr 21, 2016 · 在使用四方扁平无引线 (qfn) 封装的情况下，不太容易看到可焊接或外露引脚/端子，也就使你无法确认它们是否被成功地焊接在印刷电路板 (pcb) 上。 封装边缘有用于端子、暴露在外的覆铜，这些覆铜很容易被氧化，这使得侧壁焊锡润湿很困难。