How To Replace The Flat Package Ic - Panasonic KX-FT982LS-B Service Manual

KX-FT982LS-B / KX-FT984LS-B / KX-FT988LS-B

16.2. How to Replace the Flat Package IC

Even if you do not have the special tools (for example, a spot heater) to remove the Flat IC, with some solder (large amount), a
soldering iron and a cutter knife, you can easily remove the ICs that have more than 100 pins.
16.2.1. 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.7).
16.2.2. Flat Package IC Removal Proce-
dure
1. Put plenty of solder on the IC pins so that the pins can be
completely covered.
Note:
If the IC pins are not soldered enough, you may give
pressure to the P.C. board when cutting the pins with
a cutter.
2. Make a few cuts into the joint (between the IC and its
pins) first and then cut off the pins thoroughly.
3. While the solder melts, remove it together with the IC
pins.
When you attach a new IC to the board, remove all solder left
on the land with some tools like a soldering wire. If some solder
is left at the joint on the board, the new IC will not be attached
properly.
16.2.3. Flat Package IC Installation Proce-
dure
1. Temporarily fix the FLAT PACKAGE IC, soldering the two
marked pins.
• Check the accuracy of the IC setting with the corre-
sponding soldering foil.
2. Apply flux to all pins of the FLAT PACKAGE IC.
3. Solder the pins, sliding the soldering iron in the direction
of the arrow.
16.2.4. Bridge Modification Procedure
1. Lightly resolder the bridged portion.
2. Remove the remaining solder along the pins using a sol-
dering iron as shown in the figure below.
154