Technical Product Specification

Design and Environmental Specifications Intel® Server Board S5520UR and S5520URT TPS
Intel order number E44031-012 Revision 1.9
128
The power supply is provided with a reliable protective earth ground. All secondary circuits are
connected to protective earth ground. Resistance of the ground returns to chassis does not
exceed 1.0 mΩ. This path may be used to carry DC current.
9.3.2 Standby Outputs
The 5 VSB output is present when an AC input greater than the power supply turn-on voltage
is applied.
9.3.3 Remote Sense
The power supply has remote sense return to regulate out ground drops for all output voltages:
+3.3 V, +5 V, +12 V1, +12 V2, +12 V3, +12 V4, -12 V, and 5 VSB. The power supply uses
remote sense (3.3 VS) to regulate out drops in the system for the +3.3 V output.
The +5 V, +12 V1, +12 V2, +12 V3, +12V4, –12 V and 5 VSB outputs only use remote sense
referenced to the remote sense return signal. The remote sense input impedance to the power
supply must be greater than 200 Ω on 3.3 VS and 5 VS. This is the value of the resistor
connecting the remote sense to the output voltage internal to the power supply.
Remote sense must be able to regulate out a minimum of a 200 mV drop on the +3.3 V output.
The remote sense return must be able to regulate out a minimum of a 200 mV drop in the
power ground return. The current in any remote sense line is less than 5 mA to prevent voltage
sensing errors.
The power supply must operate within specification over the full range of voltage drops from the
power supply’s output connector to the remote sense points.
9.3.4 Voltage Regulation
The power supply output voltages must stay within the following voltage limits when operating
at steady state and dynamic loading conditions. These limits include the peak-peak ripple/noise.
Table 76. Voltage Regulation Limits
Parameter
Tolerance
Minimum
Normal
Maximum
Units
+ 3.3V - 5%/+5% +3.14 +3.30 +3.46 V
rms
+ 5V - 5%/+5% +4.75 +5.00 +5.25 V
rms
+ 12V1,2,3,4
- 5%/+5%
+11.40
+12.00
+12.60
V
rms
- 12V
- 10%/+10%
-10.80
-12.00
-13.20
V
rms
+ 5VSB
- 5%/+5%
+4.75
+5.00
+5.25
V
rms
9.3.5 Dynamic Loading
The output voltages remain within limits for the step loading and capacitive loading specified in
the following table.
The load transient repetition rate is tested between 50 Hz and 5 kHz at duty
cycles ranging from 10%-90%.
The load transient repetition rate is only a test specification. The
∆ step load may occur anywhere within the minimum load to the maximum load conditions.