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@ Take
a short length of fine bare wire and
wind it around the IC so that it shorts all the
pins of the IC, while it is still in the urethane-
polyester
cushion
or
aluminum
foil.
This
ensures
that
all the
pins
are
at
the
same
potential.
fine bare wire
:
(stripped solid hookup
wire, etc.)
partially conductive
urethane-polyester
cushion or aluminum
foil
Fig. G
® When
it is necessary
to handle
the IC with
the fingers, do not touch
any pin, and hold
the IC at the ends of its plastic-package case
as shown
in Fig. H.
-s
Fig. H
Method
of Mounting
Insert the IC while holding it with the modified
clip, and solder all the pins with the clip still
shorting the pins. (Similarly, solder all the pins
while
the
bare
shorting
wire
is still
wound
around
them.).
Remove
the clip or the bare
shorting wire only after all the pins have been
soldered.
Precaution
while Checking
C-MOS
ICs
The C-MOS
ICs (Complementary
MOS) are MOS
ICs
that
have
their
output
sections
made
up
of
N-channel
and P-channel push-pull stages to increase
their speed of operation.
If the output
terminal of
these
ICs comes into contact with B+ or B- voltage,
then
the FET
which
is ON
at that time
will either
become
shorted or open.
This is valid for all the output sections that are
connected
together
by the
interconnections.
Even
the circuits that are physically separated (and not on
the same board) can be destroyed simultaneously.
Example:
if this line is grounded,
or touches
8+ or B- bus... , the output stage
of this IC will be destroyed.
Fig. |
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