Technical Product Specification

Intel® Server System P4000IP and Intel® Workstation System P4000CR Family TPS System Power Sub-system
62 Intel order number G38159-002 Revision 1.2
Q2
2N4401
PWOK out
PWOK in
Q1
2N4401
12V
3.3VSB
R2
20
R4
820
R3
10k
R1
10k
Figure 28. PWOK Circuit Requirement
2.3.6.3 SMBAlert# Signal
This signal indicates that the power supply is experiencing a problem that the user should
investigate. This shall be asserted due to Critical events or Warning events. The signal shall
activate in the case of critical component temperature reaching a warning threshold, general
failure, over-current, over-voltage, under-voltage, failed fan. This signal may also indicate the
power supply is reaching its end of life or is operating in an environment exceeding the
specified limits.
This signal is to be asserted in parallel with LED turning solid Amber or blink Amber.
Table 66. SMBAlert# Signal Characteristics
Signal Type (Active Low)
Open collector/drain output from power supply.
Pull-up to VSB located in system.
Alert# = High
OK
Alert# = Low
Power Alert to system
MIN
MAX
Logic level low voltage, Isink=4 mA
0 V
0.4 V
Logic level high voltage, Isink=50 A
3.46 V
Sink current, Alert# = low
4 mA
Sink current, Alert# = high
50 A
Alert# rise and fall time
100 s
2.3.7 Thermal CLST
The power supply shall assert the SMBAlert signal when a temperature sensor crosses a
warning threshold.
Refer to the CRPS Common Requirements Specification for detailed requirements.
2.3.8 Power Supply Diagnostic “Black Box”
The power supply shall save the latest PMBus data and other pertinent data into nonvolatile
memory when a critical event shuts down the power supply. This data shall be accessible from
the SMBus interface with an external source providing power to the 12Vstby output.
Refer to the CRPS Common Requirements Specification for detailed requirements.