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Power On
P1-PIN #14 PS-ON
Power Switch
P1-PIN #14 PS-ON
ON
L
ON
IN
OFF
H
ON
IN
OFF
X
ON
OUT
OFF
X
OFF
X
3.5
+5V SB
The +5VSB output is always on (+5V Standby) when AC power is applied
and the power switch is turned on. The +5VSB line is capable of delivering at a
maximum of 1.5A for PC board circuit to operate.
3.6
Efficiency
65% min. at full load test.
3.7
Timing/Housekeeping/Control
3.7.1
PS-OK Signal
3.7.2
Off
PS-ON On
~
95%
10% T5
+5V/+3.3V O/P ~
PS-OK T4
T3
PW-OK Sense Level =95% of nominal T2
Note:
T2:The output voltage shall rise from <10% of nominal to within the regulation
specified in Section 2.2 within 0.1 to 20 ms.(0.1ms
£
T2
£
20ms)
T3 T4 and T5 are as following Table:
Signal Type:
+5VDC,TTL compatible
Logic level low
<0.4V while sinking 4 mA
Logic level high
Between 2.4VDC and 5VDC output while sourcing 200
m
A
High state output impedance
1K
V
from output to common
PS-OK delay
100ms < T3 < 500 ms
PS-OK rise time
T5
£
10 ms
Power down warning
T4 > 1 ms
3.7.2 PWR_OK(Power Good)
PWR_OK is a “power good” signal. It should be asserted high by the power supply to indicate that the
+5VDC and +3.3VDC outputs are above the undervoltage thresholds listed in Section 3.2 . PWR_OK
should be descended to a low state when either the +5VDC or the +3.3VDC output voltages falls below the
undervoltage threshold, or when the main power has been removed for a time long enough that power
supply operation cannot be guaranteed beyond the hold-up time. The electrical and timing characteristics of
the PWR_OK signal are given in Section 4.7.1.
