2. Conformally Coated
Components:
2.1 A detailed repair process for
Conformal Coated components is outside the scope of
this procedure as they usually contain smaller lead
counts than discussed in this document, and are
usually found in products subject to frequency of
handling and environmental hazards, refer to Motorola
document 68-80309F92, available from Motorola APD or
APE.
As a summary, if coating exist, it
is necessary to carry out a Eutectic Removal only,
the Reflow Removal procedure outlined in 7.0 of this
document is not possible. The component is removed by
setting the Chipmaster to the removal temperature as
explained below, (5.0) and using a probe supplied in
the kit, gently pry each corner of the component as
the coating starts to break down under temperature,
(Illustration # 3), be careful not to apply too much
pressure so as to damage the component or contact
area. All the coating material should now be cleaned
from the QFP contact pads and component leads,
(should the component need to be reused), Use the pad
prep cleaner included in the Motorola # 81-30303-E45,
APE # 8100-1097, SMD Tool Kit to clean the contact
area after removal and use the knife probes to
collect all residues and finally clean with a lint
free Antistatic wipe, APE # 8200-1500.
Illustration # 3
3. Required Materials:
Item Description APE Model #
Motorola Model #
1. Chipmaster 8100-1003
R1319A (110V) or R1321A (220V)
2. SMT Tweeze/Solder Iron EX-755 R1366
3. SMT Tool Kit 8100-1097 01-80303E45
4. Nozzle for QFP208 8100-1414 66-80332E92
5. Chipmaster Manual 8100-0609 68-8309F40 (Supplied
with Item 1)
6. Lint Free Antistatic Wipes 8200-1500
7. Hand 2.3 Dioptic Magnifier 8200-1200
4. Selecting the correct
Profile.
The Chipmaster 8100-1003, includes
the optional Profile Storage Controller, which
includes four (4) carefully designed and pre prepared
profiles for most BGA and QFP/SMT applications,
(Illustration # 3a). In reworking QFP components
greater than 100 lead count Profile # 2, is
recommended and will provide the correct
"Temperature Ramp" and "Soak" so
as not to stress the component under repair and
protect the adjacent components from degradation or
damage. Should the circuit board be of a heavy metal
or ceramic construction, Profile # 3 is recommended,
to increase the calorific energy to the board (Not
Temperature).
Illustration # 3a
To select Profile # 2, from the "Operator
View Display" (Illustration # 4) press the
INDEX key on the controller ONCE to enter the "Operator
Menu" then press the INDEX Key, ONCE more,
to reach the "Profile Field" ; then press
either the "UP" or "DOWN" arrow
to reach the desired Profile (RED L.E.D. display.
Then press ENTER. Press the INDEX key THREE times to
return to the "Operator View Display". See
Chipmaster Manual for complete explanation of
controller and features.
Illustration # 4
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