Technical Product Specification

2BPower Sub-System Intel® Server System SR1690WB TPS
Revision 1.7
Intel order number: E72797-009
16
3.5 Protection Circuits
Protection circuits inside the power supply will cause only the power supply’s main outputs to
shut down. If the power supply latches off due to a protection circuit tripping, an AC cycle
OFF for 15 sec and a PSON
#
cycle HIGH for 1 sec shall be able to reset the power supply.
3.5.1 Over-Current Protection (OCP)
The power supply will have current limits to prevent the +3.3V, +5V, and +12V outputs from
exceeding the values shown in the following table. If the current limits are exceeded, the
power supply will shut down and latch off. You can clear the latch by toggling the PSON
#
signal or by an AC power interruption. The power supply will not be damaged from repeated
power cycling in this condition. -12V and 5VSB will be protected under over-current or
shorted conditions so that no damage can occur to the power supply. Auto-recovery feature
is a requirement on 5 VSB rail.
Table 14. Over-current Protection (OCP)
Voltage
Over Current Limit (Iout limit)
+3.3 V
110% minimum (= 22A) ; 150% maximum (= 30A)
+5 V
110% min (= 33A); 150% max (= 40A)
+12 V1
25A min; 30A max
+12 V2
25A min; 30A max
+12 V3
18A min; 20A max
+12 V4
18A min; 20A max
-12 V
0.625A min; 2.0A max
5 V
SB
6.0A max
3.5.2 Over-voltage Protection (OVP)
The power supply over-voltage protection is locally sensed. The power supply will shut down
and latch off after an over-voltage condition occurs. You can clear this latch by toggling the
PSON
#
signal or by an AC power interruption. The following table contains the over-voltage
limits. The values are measured at the output of the power supply’s connectors. The voltage
will never exceed the maximum levels when measured at the power pins of the power supply
connector during any single point of fail. The voltage will never trip any lower than the
minimum levels when measured at the power pins of the power supply connector.
Exception: +5V
SB
rail should be able to recover after an over-voltage condition occurs.
Table 15. Over-Voltage Protection (OVP) Limits
Output Voltage
MIN (V)
MAX (V)
+3.3V
+3.9
+4.5
+5V
+5.7
+6.2
+12V1,2, 3, 4
+13.3
+14.5
-12V
-13.3
-14.5
+5V
SB
+5.7
+6.5
3.5.3 Over-temperature Protection (OTP)
The power supply is 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 5V
SB
remains always on. The OTP circuit has built-in
hysteresis such that the power supply will not oscillate on and off due to a temperature
recovering condition. The OTP trip level has a minimum of 4ºC of ambient
temperature hysteresis.