IBM 5150 PC Technical Reference (6025005, August, 1981) (PDF)

Important Operating Characteristics
Over Voltage/Current Protection
PRIMARY (INPUT)
VOLTAGE
NOMINAL
VAC
TYPE PROTECTION
RATING
AMPS
120 60 Hz FUSE TYPE 2 SOC SD4 2AMPS
Power On/Off Cycle: When the supply is turned off for a maximum of
5 seconds, and then turned on, the power good signal will be
regenerated.
Signal Requirements
The power good signal indicated that there is adequate power to
continue processing. If the power goes below the specified levels,
the power good signal triggers a system shut-down.
The Power Supply. Provides a power good signal out, to indicate the
presence ofthe +/-5V and +/-12Voutputs are above the sense level
defined in the chart below, the power good signal is an up level (2.4V to
5 .5V), TTL compatible and capable of sourcing 60 VA. When any of
the four sensed output voltages is below its sense level voltage as
defined in the chart below, the power good signal is down level (OV to
O.4V), TTL compatible and capable of sinking 500 VA. The power
good signal (after all levels of the output voltage are good) has a turn
on delay of 100 MS, but no greater than 500 MS.
The sense levels of the +/-5V and +/-12V outputs are:
"'"
OUTPUT
MIN
SENSE VOLTAGE
NOMINAL
MAX
+5V +3.7 +4.0 +4.3
-5V -3.7 -4.0 -4.3
+12V +8.5 +9.6 +10.5
-12V -8.5 -9.6 -10.5
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