Technical Product Specification

Power Supply Specification Guidelines Intel
®
Server Board S2400EP TPS
Intel order number G50763-002 Revision 2.0
116
12.2.6 Capacitive Loading
The power supply should be stable and meet all requirements within the following capacitive
loading range.
Table 59. Capacitive Loading Conditions
Output
Min
Max
Units
+3.3V
250
5000
F
+5V
400
5000
F
+12V
500
8000
F
-12V
1
350
F
+5VSB
20
350
F
12.2.7 Ripple/Noise
The maximum allowed ripple/noise output of the power supply is defined in below table. This is
measured over a bandwidth of 10Hz to 20MHz at the power supply output connectors. A 10F
tantalum capacitor in parallel with a 0.1F ceramic capacitor is placed at the point
of measurement.
Table 60. Ripple and Noise
+3.3V
+5V
+12V1, +12V2, +12V3
-12V
+5 VSB
50 mVp-p
50 mVp-p
120 mVp-p
120 mVp-p
50 mVp-p
12.2.8 Timing Requirements
These are the timing requirements for the power supply operation. The output voltages rise
from 10% to within regulation limits (T
vout_rise
) within 2 to 50ms, except for 5VSB - it is allowed to
rise from 1 to 25ms. The +3.3V, +5V and +12V1, +12V2, +12V3 output voltages start to rise
approximately at the same time. All outputs rise monotonically. Each output voltage reach
regulation within 50ms (T
vout_on
) of each other during turn on the power supply. Each output
voltage fall out of regulation within 400ms (T
vout_off
) of each other during turn off. Table 54 shows
the timing requirements for the power supply being turned on and off via the AC input, with
PSON held low and the PSON signal, with the AC input applied. All timing requirements are
met for the cross loading condition in the following table.
Table 61. Output Voltage Timing
Item
Description
Minimum
Maximum
Units
T
vout_rise
Output voltage rise time from each main output.
2
50
ms
Output rise time for the 5Vstby output.
1
25
ms
T
vout_on
All main outputs must be within regulation of each other within
this time.
50
ms
T
vout_off
All main outputs must leave regulation within this time.
400
ms