Technical Product Specification

System Power Sub-system Intel® Server System P4000IP and Intel® Workstation System P4000CR Family TPS
Revision 1.2 Intel order number G38159-002
33
Table 22. Over Current Protection
Output
VOLTAGE
Input voltage
range
Over Current Limits
+12V
90 – 264VAC
72A min; 78A max
12VSB
90 – 264VAC
2.5A min; 3.5A max
2.1.5.2 Over Voltage Protection (OVP)
The power supply over voltage protection is locally sensed. The power supply shuts down and
latches off after an over voltage condition occurs. This latch is cleared by toggling the PSON
#
signal or by an AC power interruption. The values are measured at the output of the power
supply’s connectors. The voltage does not exceed the maximum levels when measured at the
power connectors of the power supply connector during any single point of fail. The voltage
doesn’t trip any lower than the minimum levels when measured at the power connector.
12VSBwill be auto-recovered after removing OVP limit.
Table 23. Over Voltage Protection (OVP) Limits for 750W PSU
Output voltage
Min (v)
Max (v)
+12V
13.0
14.5
+12VSB
13.0
14.5
2.1.5.3 Over Temperature Protection (OTP)
The power supply will be protected against over temperature conditions caused by loss of fan
cooling or excessive ambient temperature. In an OTP condition the PSU will shut down. When
the power supply temperature drops to within specified limits, the power supply shall restore
power automatically, while the 12VSB remains always on. The OTP circuit must have built in
margin such that the power supply will not oscillate on and off due to temperature recovering
condition. The OTP trip level shall have a minimum of 4C of ambient temperature margin.
2.1.6 Control and Indicator Functions
The following sections define the input and output signals from the power supply. Signals that
can be defined as low true use the following convention: Signal# = low true.
2.1.6.1 PSON# Input Signal
The PSON
#
signal is required to remotely turn on/off the power supply. PSON
#
is an active low
signal that turns on the +12V power rail. When this signal is not pulled low by the system, or left
open, the outputs (except the +12VSB) turn off. This signal is pulled to a standby voltage by a
pull-up resistor internal to the power supply.
Table 24. PSON# Signal Characteristic
Signal Type
Accepts an open collector/drain input from the system. Pull-
up to VSB located in power supply.
PSON# = Low
ON
PSON# = High or Open
OFF