Panasonic BB-HCM547A, Руководство по обслуживанию

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BB-HCM547A
7.21. How to Replace a Flat Package IC
7.21.1. Preparation
• PbF (: Pb free) Solder
• Soldering Iron
Tip Temperature of 700
°
F ± 20
°
F (370
°
C ± 10
°
C)
Note: We recommend a 30 to 40 Watt soldering iron. An
expert may be able to use a 60 to 80 Watt iron where some-
one with less experience could overheat and damage the
PCB foil.
• Flux
Recommended Flux: Specific Gravity
→
0.82.
Type
→
RMA (lower residue, non-cleaning type)
Note: See About Lead Free Solder (PbF: Pb free) (P.3).
7.21.2. Procedure
1. Tack the flat pack IC to the PCB by temporarily soldering
two diagonally opposite pins in the correct positions on
the PCB.
Be certain each pin is located over the correct pad on the PCB.
2. Apply flux to all of the pins on the IC.
3. Being careful to not unsolder the tack points, slide the sol-
dering iron along the tips of the pins while feeding enough
solder to the tip so that it flows under the pins as they are
heated.
7.21.3. Removing Solder from Between
Pins
1. Add a small amount of solder to the bridged pins.
2. With a hot iron, use a sweeping motion along the flat part
of the pin to draw the solder from between the adjacent
pads.