Outline
This procedure covers manual tinning of QFP and PLCC components.
Caution: Due to the need to completely control the rates of immersion and emersion of the QFP and PLCC component leads and the dwell times in and between each process step, a robotic hot solder dip is recommended for QFP and PLCC component tinning. Semi-automatic or purely manual solder dipping processes may not be capable of completely controlling the rates of immersion and emersion of the QFP and PLCC component leads and only provide approximate dwell dipping times in the solder bath. Greater variation in the process may cause a higher chance of damage, including latent reliability problems. Manual dipping required for full solder finish replacement is different than manual dipping currently practiced for meeting solderability requirements because of the increased need for 100% coverage on the QFP and PLCC components leads to prevent whisker growth. Certain electronic component package styles may not lend themselves to robotic hot solder dipping and may require alternative processing. Note: For robotic thinning refer to 10.6.2 Tinning, QFP / PLCC Components, Robotic.
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Images and Figures![]()
QFP and PLCC Components
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Figure 1. Solder pot.
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Figure 2. Vacuum pickup tool.
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Figure 3. A variety of tweezers depending on the chip component size.
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Figure 4. Hot plate used to preheat the components to reduce thermal shock.
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Procedure
Procedure
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10.6.1 Tinning, QFP/PLCC Components, Manual
This procedure covers manual tinning of QFP and PLCC components.