Intel®
Server
System SR1625UR TPS
Power Subsystem
Revision 1.5
Intel order number E47487-007
25
3.8.2
Over-voltage Protection (OVP)
Each DC/DC converter output on the PDB has individual OVP protection circuits built in and
they are locally sensed. The PS and PDB shut down and latch off after an over-voltage
condition occurs. This latch is cleared by toggling the PSON
#
signal or by an AC power
interruption. The over-voltage limits are measured at the PDB harness connectors and are
listed in the following table. The voltage never exceeds the maximum levels when measured at
the power pins of the output harness connector during any single point of fail. The voltage
never trips any lower than the minimum levels when measured at the power pins of the PDB
connector.
Table 18. Over-voltage Protection (OVP) Limits
Output Voltage
OVP Minimum (V)
OVP Maximum (V)
+3.3 V
3.9
4.5
+5 V
5.7
6.2
+12 V1,2, 3, 4
13.3
14.5
-12 V
-13.3
-14.5
+5 VSB
5.7
6.5
3.8.3
Over-temperature Protection (OTP)
The PS and PDB are protected against over-temperature conditions caused by loss of fan
cooling, excessive ambient temperature, or excessive loading. Two sensing points are placed at
hot spots: one near the exterior face and the other near the interior face of the module. In an
OTP condition, the PSU shuts down. When the power supply temperature drops to within
specified limits, the power supply restores the power automatically, while 5 VSB always remains
on. The OTP circuit must have built in hysteresis such that the power supply does not oscillate
on and off due to a temperature recovery condition. The OTP trip level has a minimum of 4°C of
ambient temperature hysteresis.
3.9
Power Supply Status LED
Each power supply module has a single bi-color LED to indicate power supply status. The LED
operation is defined in the following table:
Table 19. LED Indicators
Power Supply Condition
Bi-Color LED
No AC power to all power supplies
Off
No AC power to this PSU only (for 1+1 configuration)
or
Power supply critical event causing a shutdown:
failure, fuse blown (1+1 only), OCP, OVP, Fan Failed
Amber
Power supply warning events where the power supply continues to
operate: high temp, high power, high current, slow fan.
1 Hz Blink Amber
AC present/Only 5 VSB on (PS Off)
1 Hz Blink Green
Output ON and OK
Green
The LED is visible on the rear panel of each installed power supply module.
