Philips VR120 Service Manual page 54

GB 54 5.
• Using a soldering iron
a. Use unsoldering braid to remove the solder from all
pins of the Flat Pack IC. Apply solder flux to all pins of the
Flat Pack IC, to allow easy removal.
Flat Pack IC
Soldering iron
b. Lift up each lead of the Flat Pack IC individually, using a
sharp pin or non-solder wire (iron wire), while heating the
pins using a fine tip soldering iron or a hot air blower.
Soldering iron
• Using iron wire
a. Use unsoldering braid to remove the solder from all pins of
the Flat Pack IC. Apply solder flux to all pins of the Flat Pack
IC, to allow easy removal.
b. Affix the wire to workbench or solid mounting point ( see
figure 5-3 )
c. Pull up the wire as the solder melts in order to lift the IC
lead from the P.C.B. contact pad, while heating the pins
using a fine-tip soldering iron or hot air blower.
Hot air blower
Pull up gently
to remove
Figure 5-4
Note:
When using a soldering iron care must be taken to ensure
that the Flat Pack lC is not held by glue or the P.C.B. may be
damaged if force is used.
If the IC is glued, heat the IC with hot air to loosen the glue.
VR120 Service modes, Repair tips
Unsoldering braid
Sharp iron
Solid mounting point
Iron wire
... or soldering iro
• Using a special removal device
a. Apply extra tin-lead solder onto the pins
b. Heat the IC to melt the glue which has been used to affix it
c. Use a solder removing device with a special punch which
matches the contours of the IC to remove the IC.
At the other corners there are printed conductors which may
be damaged!
Solder
removing
device
Control µP
Figure 5-5
How to install the Flat Pack IC
a. Use unsoldering braid to remove the solder from the foil of
each pin of the Flat Pack lC on the P.C.B. in order to install
the replacement Flat Pack IC more easily.
b. The "dot" mark on the Flat Pack IC indicates pin 1.
Make sure this mark matches the 1 on the P.C.B. when
positioning for installation. Then pre-solder the four corners
of the d. Flat Pack IC. ( see figure 5-5 ).
Example
Pin 1 on Flat Pack IC is market by a " ".
Figure 5-6
PCB