Sony STR-S5L - Page 4

o
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
wtre.
etc.
)
Precaution
while Checking C-MOS
lCs
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
B+ or B- bus.
.
.
,
the
output stage
of
this lC will be destroyed.
Fis.
I
I
partially
conductive
u rethane-polyester
cushion or aluminum
foil
Fis.
G
o
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 Fie.
H.
Fis.
H
5. 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.).
Re'move the clip
or the
bare
shorting
wire
only
after
all the
pins
have been
soldered.
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