Panasonic KX-NS500AG, Service Manual

Page: 39 / 191

39
KX-NS500AG
11.2. How to Replace the LLP (Leadless Leadframe Package) IC and IC
ground plate
11.2.1. 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 someone with less
experience could overheat and damage the PCB foil.
• Hot Air Desoldering Tool
Temperature: 608

F ± 68

F (320

C ± 20

C)
11.2.2. Caution
• To replace the IC efficiently, choose the right sized nozzle of the hot air desoldering tool that matches the IC package.
• Be careful about the temperature of the hot air desoldering tool not to damage the PCB and/or IC.
11.2.3. How to Remove the IC
1. Heat the IC with a hot air desoldering tool through the
P.C.Board.
2. Pick up the IC with tweezers, etc. when the solder is
melted completely.
Note:
• Be careful not to touch the peripheral parts with twee-
zers, etc. They are unstable.
3. After removing the IC, clean the P.C.Board of residual sol-
der.
11.2.4. How to Install the IC
1. Place the solder a little on the land where the radiation
GND pad on IC bottom is to be attached.
2. Place the solder a little on the land where IC pins are to
be attached, then place the IC.
Note:
• When placing the IC, the positioning should be done very
carefully.
3. Heat the IC with a hot air desoldering tool through the
P.C.Board until the solder on IC bottom is melted.
Note:
• Be sure to place it precisely, controlling the air volume of
the hot air desoldering tool.
4. After soldering, confirm there are no short and open cir-
cuits with visual inspection.