Dynamic Loading; Capacitive Loading; Closed-Loop Stability; Common Mode Noise - Intel S5000XAL Technical Product Specification

Power and Environmental Specifications
8.2.8
The output voltages shall remain within limits for the step loading and capacitive loading specified in the
table below. The load transient repetition rate shall be 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 Δ step load
may occur anywhere within the MIN load to the MAX load conditions.
Output
+3.3V
+5V
12V1+12V2+12V3+12
V4
+5VSB
Notes:
1) Step loads on each 12V output may happen simultaneously.
2) The +12V should be tested with 2200μF evenly split between the four +12V rails.
8.2.9
The power supply shall be stable and meet all requirements with the following capacitive loading ranges.
+12V1,2,3,4
8.2.10
The power supply shall be unconditionally stable under all line/load/transient load conditions including
capacitive load ranges. A minimum of: 45 degrees phase margin and -10dB-gain margin is required.
Closed-loop stability must be ensured at the maximum and minimum loads as applicable.
8.2.11
The common mode noise on any output shall not exceed 350 mV pk-pk over the frequency band of 10Hz
to 30MHz.
1. The measurement shall be made across a 100 Ω resistor between each of the DC outputs,
including ground, at the DC power connector and chassis ground (power subsystem enclosure).
2. The test set-up shall use an FET probe such as Tektronix* model P6046 or equivalent.
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Dynamic Loading

Table 39. Transient Load Requirements

Δ Step Load Size
(See note 2)
5.0A
6.0A
28.0A
0.5A

Capacitive Loading

Table 40. Capacitive Loading Conditions

Output MIN
+3.3V 250
+5V 400
500 each
-12V 1
+5VSB 20

Closed-Loop Stability

Common Mode Noise

Revision 1.4
Intel order number: D31979-007
®
Intel Server Board S5000PAL / S5000XAL TPS
Load Slew Rate Test capacitive Load
250 μF
0.25 A/μsec
400 μF
0.25 A/μsec
2200 μF
0.25 A/μsec
20 μF
0.25 A/μsec
MAX Units
μF
6,800
4,700 μF
11,000 μF
μF
350
350 μF
1,2