Hitachi VTMX900EUK Service Manual page 8

2-2
a. Prepare the hot air Flat Pack IC unsoldering equipment. Then
apply hot air to Flat Pack lC for 5 - 8 seconds.
b. Remove the Flat Pack lC with tweezers while applying the hot
air.
CAUTION:
To avoid damage, do not apply the hot air to the chip parts around
the Flat Pack lC for long periods.
C.B.A.
Masking
tape
Tweezers
Fig. 2-5
Put masking tape around the Flat Pack lC to protect adjacent parts.
2. The Flat Pack IC is fixed to the P.C.B. with glue; therefore take
care not to break or damage any foil under the lC or on each pin
when removing it.
• 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
Fig. 2-6
GB
Hot air Flat Pack
IC unsoldering
equipment
FLAT PACK IC
Unsoldering
braid
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
Fig. 2-7
• 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 Fig. 2-8)
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
Fig. 2-8
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.
Sharp pin
Solid mounting
point
Iron wire
... or soldering iron