Intel SPSH4 - Server Platform - 0 MB RAM, Technical Product Specification

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SPSH4 Server SystemTechnical Product Specification
Revision 1.11
Intel reference number 10736
33
4.2.6 Control Signals
4.2.6.1 PSON
The PSON
#
signal is required to remotely turn on/off the power supply. PSON
#
is an active low
signal that turns on the 3.3V, 5V, 12V, and -12V power rails. When this signal is not pulled low
by the system, or if it is left open, the outputs (except the 5VSB) turn off. This signal is pulled to
a standby voltage by a pull-up resistor internal to the power supply. See Figure 15 for the timing
diagram.
Table 26: PSON Signal Characteristic
Signal Type Accepts an open collector/drain input from the
system. Pull-up to VSB located in power supply.
PSON
#
= Low, PSKILL = Low
ON
PSON
#
= Open, PSKILL = Low or Open OFF
PSON
#
= Low, PSKILL = Open OFF
MIN MAX
Logic level low (power supply ON)
0V 1.0V
Logic level high (power supply OFF) 2.0V 5.25V
Source current, Vpson = low 4ma
Power up delay: T
pson_on_delay
5msec 400msec
Power down delay: T
pson_off_delay
1.1msec
PWOK delay: T
pson_pwok
50msec
4.2.6.2 PWOK
PWOK is a power good signal and will be pulled HIGH by the power supply to indicate that all
the outputs are within the regulation limits of the power supply. When any output voltage falls
below regulation limits or when AC power has been removed for a time sufficiently long so that
power supply operation is no longer guaranteed, PWOK will be de-asserted to a LOW state.
See Figure 15 for a representation of the timing characteristics of PWOK. The start of the
PWOK delay time is inhibited as long as any power supply output is in current limit.
Table 27: PWOK Signal Characteristics
Signal Type Open collector/drain output from power supply.
Pull-up to VSB located power supply.
PWOK = High Power Good
PWOK = Low Power Not Good
MIN MAX
Logic level low voltage, Isink=4mA
0V 0.4V
Logic level high voltage, Isource=200
µ
A
2.4V 5.25V
Sink current, PWOK = low
4mA
Source current, PWOK = high
2mA
PWOK delay: T
pwok_on
100ms 1000ms
PWOK rise and fall time
100
µ
sec
Power down delay: T
pwok_off
1ms 200mSec