Connection
to Power Supply
If
you
are
installing
the PPM-20300
yourself,
the
final
step
is
attaching the power
supply
cable
to
the
main-
board
at
connector J9,
which
is
located
in
the upper
right
quadrant
of
the board. There are some cables
0n
the
power supply.
Be
sure the
four black
wires
of
the power
supply
are
located at
the
middle
of
the power connectors.
Refer
to
the
figure below. Pin
1
is
numbered
in
the
picture
for your
convenience.
The pinouts for
the connectors
at
J9 are as
follows:
Pin
Assignment
Power Good
+5 VDC
+12
VDC
-12 VDC
Ground
Ground
Ground
Ground
-5 VDC
+5 VDC
+5 VDC
+5 VDC
(OGDVQU‘IACONA
_A
O
_A
.1
_A
N
24
)0
)DO
)0
Choosing a Power Supply
The power supply provides
a
"power-good” signal to
indicate
proper operation
of
the power
supply. The
power-good signal
is
a
TTL-compatible high level for
normal
operation
or
a
low
level for fault conditions.
It
the
power-good signal works
well,
the system
will
function properly. Otherwise,
the
CMOS
RAM
data
setting
will
be lost.
You
are advised
to
use the
internal
power
fail
detect
circuit (pins
one and
two
of
jumper
W11
shorted)
if
the
external
power-good signal
does
not work well.
Following
are some guidelines
for
choosing a suitable
power
supply:
-
The
power-good
signal
should have a
turn-on
delay
of
at
least 200ms,
but no longer
than
500ms.
(This
means that the power-good
sig-
nal
goes
to
a
high level later
than
+5V).
-
The power-good signal
goes
to
a
low
level at
least
100ms
before
+5V falls below
the
regula-
tion
limits
when the
power
is
turned
off.
To
install
a power
supply
in
your
system
case
you may
need
to
consult
your
dealer
for information.
Neverthe-
less,
installation
is
a
simple
and
straightforward pro-
cedure.
25
Summary of Contents for Mini 80386SX
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