Page 1
SSI
ERP2U
(Entry Redundant Power 2U)
Power Supply Design Guide
A Server System Infrastructure (SSI) Specification
For 2U Rack Chassis Power Supplies
Version 2.31
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SSI
ERP2U Power Supply Design Guide, V2.31
Revision History
Orig./Rev. Description of Changes
2.0
2.2
2.3
2.31
Post design guide
Added higher power levels up to 800W.
Added 350mm depth.
Removed lower power levels.
Added standby fan operation.
Added option for tighter 12V regulation.
Added 12V4.
Add new SSI efficiency requirements (recommended level & loading conditions).
Reduced holdup time requirements to 75% of max load.
Increase 12V rails for >650W.
Tpwok_on max time reduced to 500msec.
Change 5VSB to 3.0A for >650W.
Added reference to PSMI spec.
Modified SMBus section (FRU and PSMI) to 3.3V with 5V tolerance.
Modified 240VA section; removed common plane, change to <20A for all 12V outputs.
Updated sound power & airflow requirements
Remove reference to split and common rails
Updated efficiency testing method
Increase 5V current to 30A and combined 3.3V/5V power to 160W for the 700-800W power levels.
Increase 12V1/2 current for 550W-650W power levels. Relax require regulation limits. Added
optional regulation limits.
Fixed error in 3.3V and 5V loading. Increased 3.3V/5V combined power.
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ERP2U Power Supply Design Guide, V2.31
Disclaimer:
THIS SPECIFICATION IS PROVIDED "AS IS" WITH NO WARRANTIES
WHATSOEVER, INCLUDING ANY WARRANTY OF MERCHANTABILITY,
NONINFRINGEMENT, FITNESS FOR ANY PARTICULAR PURPOSE, OR ANY
WARRANTY OTHERWISE ARISING OUT OF ANY PROPOSAL, SPECIFICATION OR
SAMPLE. WITHOUT LIMITATION, THE PROMOTERS (Intel Corporation, NEC
Corporation, Dell Computer Corporation, Data General a division of EMC Corporation,
Compaq Computer Corporation, Silicon Graphics Inc., and International Business
Machines Corporation) DISCL AIM ALL LIABILITY FOR COST OF PROCUREMENT OF
SUBSTITUTE GOODS OR SERVICES, LOST PROFITS, LOSS OF USE, LOSS OF
DATA OR ANY INCIDENTAL, CONSEQUENTIAL, DIRECT, INDIRECT, OR SPECIAL
AMAGES, WHETHER UNDER CONTRACT, TORT, WARRANTY OR OTHERWISE,
ARISING IN ANY WAY OUT OF USE OR RELIANCE UPON THIS SPECIFICATION OR
ANY INFORMATION HEREIN.
The Promoters disclaim all liability, including liability for infringement of any proprietary
rights, relating to use of information in this specification. No license, express or implied,
by estoppel or otherwise, to any intellectual property rights is granted herein.
This specification and the information herein is the confidential and trade secret
information of the Promoters. Use, reproduction and disclosure of this specification and
the information herein are subject to the terms of the S.S.I. Specification Adopter's
Agreement.
Copyright © Intel Corporation, Dell Computer Corporation, Hewlett Packard Company, Silicon Graphics Inc.,
International Business Machines Corporation, 2002-2003.
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ERP2U Power Supply Design Guide, V2.31
Contents
1 Purpose.......................................................................................................................................................... 7
2 Conceptual Overview ................................................................................................................................... 7
3 Definitions/Terms/Acronyms....................................................................................................................... 8
4 Mechanical Overview ................................................................................................................................... 9
4.1 Acoustic Requirements............................................................................................................................. 10
4.2 Airflow Requirements................................................................................................................................ 10
4.3 Temperature Requirements...................................................................................................................... 10
5 AC Input Requirements.............................................................................................................................. 11
5.1 AC Inlet Connector.................................................................................................................................... 11
5.2 Redundant AC Inlets................................................................................................................................. 11
5.3 AC Input Voltage Specification ................................................................................................................. 11
5.4 Input Under Voltage.................................................................................................................................. 12
5.5 Efficiency................................................................................................................................................... 12
5.6 AC Line Dropout........................................................................................................................................ 12
5.7 AC Line Fuse ............................................................................................................................................ 13
5.8 AC Inrush .................................................................................................................................................. 13
5.9 AC Line Transient Specification................................................................................................................ 13
5.10 AC Line Fast Transient Specification.................................................................................................... 14
6 DC Output Specification ............................................................................................................................ 15
6.1 Output Connectors.................................................................................................................................... 15
6.1.1 Required Baseboard power connector..............................................................................................15
6.1.2 +12V4 Baseboard Power Connector.................................................................................................16
6.1.3 Required Peripheral Power Connectors............................................................................................16
6.1.4 Required Floppy Power Connector.................................................................................................... 16
6.1.5 Serial ATA Power Connector............................................................................................................. 17
6.1.6 Server Signal Connector.................................................................................................................... 17
6.2 Grounding.................................................................................................................................................. 18
6.3 Remote Sense .......................................................................................................................................... 18
6.4 Output Power/Currents ............................................................................................................................. 18
6.4.1 Standby Outputs................................................................................................................................ 21
6.4.2 Fan operation in standby mode......................................................................................................... 21
6.5 Voltage Regulation....................................................................................................................................21
6.6 Dynamic Loading ...................................................................................................................................... 22
6.7 Capacitive Loading.................................................................................................................................... 22
6.8 Ripple / Noise............................................................................................................................................ 23
6.9 Redundancy.............................................................................................................................................. 24
6.10 Hot Swap Requirements........................................................................................................................ 24
6.11 Timing Requirements ............................................................................................................................ 25
7 Protection Circuits...................................................................................................................................... 28
7.1 Current Limit.............................................................................................................................................. 28
7.2 240VA Protection...................................................................................................................................... 28
7.3 Over Voltage Protection............................................................................................................................ 29
7.4 Over Temperature Protection.................................................................................................................... 29
8 Control and Indicator Functions............................................................................................................... 30
8.1 PSON#...................................................................................................................................................... 30
8.2 PWOK (Power OK) ................................................................................................................................... 31
8.3 SMBus Communication............................................................................................................................. 31
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ERP2U Power Supply Design Guide, V2.31
8.4
Power Supply Management Interface....................................................................................................... 31
8.5 Field Replacement Unit (FRU) Signals..................................................................................................... 32
8.5.1 Module FRU Data.............................................................................................................................. 32
8.5.2 Module FRU Data Format.................................................................................................................. 32
8.6 LED Indicators........................................................................................................................................... 33
9 MTBF............................................................................................................................................................ 35
10 Agency Requirements................................................................................................................................ 35
Figures
Figure 1: Enclosure Drawing .................................................................................................................................... 9
Figure 2 System Airflow Impedance........................................................................................................................ 10
Figure 3: Output Voltage Timing............................................................................................................................. 25
Figure 4: Turn On/Off Timing.................................................................................................................................. 27
Figure 5: PSON# Signal Characteristics ................................................................................................................ 30
Tables
Table 1 Recommended Acoustic Sound Power Levels.......................................................................................... 10
Table 2: Thermal Requirements............................................................................................................................. 11
Table 3: AC Input Rating........................................................................................................................................ 12
Table 4: Efficiency .................................................................................................................................................. 12
Table 5 Efficiency Loading Table .............................................................................. Error! Bookmark not defined.
Table 6: AC Line Sag Transient Performance........................................................................................................ 13
Table 7: AC Line Surge Transient Performance .................................................................................................... 14
Table 8: P1 Baseboard Power Connector.............................................................................................................. 15
Table 9: Processor Power Connector..................................................................................................................... 15
Table 10: Peripheral Power Connectors................................................................................................................. 16
Table 11: P9 Floppy Power Connector................................................................................................................... 16
Table 12: Floppy Power Connector....................................................................................................................... 17
Table 13: Server Signal Connector ........................................................................................................................ 17
Table 14: 550 W Load Ratings............................................................................................................................... 18
Table 15: 600 W Load Ratings............................................................................................................................... 19
Table 16: 650 W Load Ratings............................................................................................................................... 19
Table 17: 700 W Load Ratings............................................................................................................................... 20
Table 18: 750 W Load Ratings............................................................................................................................... 20
Table 19: 800 W Load Ratings............................................................................................................................... 21
Table 20: Voltage Regulation Limits....................................................................................................................... 22
Table 21: Optional +5V Regulation Limits.............................................................................................................. 22
Table 22: Transient Load Requirements................................................................................................................ 22
Table 23: Capacitve Loading Conditions................................................................................................................ 23
Table 24: Ripple and Noise.................................................................................................................................... 23
Table 25: Output Voltage Timing............................................................................................................................ 25
Table 26: Turn On/Off Timing.................................................................................................................................26
Table 27: Over Current Protection.......................................................................................................................... 28
Table 28: Over Current Protection.......................................................................................................................... 28
Table 29: Over Voltage Limits................................................................................................................................ 29
Table 30: PSON# Signal Characteristic.................................................................................................................. 30
Table 31: PWOK Signal Characteristics................................................................................................................. 31
Table 32: FRU Device Information......................................................................................................................... 32
Table 33: FRU Device Product Information Area................................................................................................... 32
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ERP2U Power Supply Design Guide, V2.31
Table 34: FRU Device Product Information Area................................................................................................... 33
Table 35: LED Indicators........................................................................................................................................ 34
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ERP2U Power Supply Design Guide, V2.31
1
Purpose
This 2U Rack Power Supply Design Guide defines a common redu ndant power sub-system used in 2U rack
mount servers. The power sub-system is made up of a cage and hot swap redundant power modules. This
Design Guide covers the mechanical and electrical require ments of this power sub-system. The requirements of
the individual hot swap modules are left open. This power sub-system may range from 550 to 800 watts and is
used in a hot swap redundant configuration. The scope of this document defines the requirements for this power
assembly. The parameters of this supply are defined in this design guide for open industry use.
Conceptual Overview
2
In the Entry server market, the bulk power system must source power on sever al out put rails.
These rails are typically as follows:
• +3.3 V (optional from bulk supply)
• +5 V (optional from bulk supply)
• +12 V
• –12 V
• 5 V standby
NOTE
Local DC-DC converters shall be utilized for processor power, and will ideally convert power from the +12 V
rail, however, they may also convert power from other rails.
The bulk power system may be a n+1 redundant power system or a non-redundant power system.
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ERP2U Power Supply Design Guide, V2.31
3 Definitions/Terms/Acronyms
Required
Recommended
Optional
Autoranging
CFM
Dropout
Latch Off
Monotonically
Noise
Overcurrent
PFC
Ripple
Rise Time
Sag
Surge
VSB or Standby Voltage
MTBF
PWOK
The status given to items within this design guide, which are required to
meet SSI guidelines and a large majority of system applications.
The status given to items within this design guide which are not required to
meet SSI guidelines, however, are required by many system applications.
The status given to items within this design guide, which are not required to
meet SSI guidelines, however, some system applications may optionally
use these features.
A power supply that automatically senses and adjusts itself to the proper
input voltage range (110 VAC or 220 VAC). No manual switches or
manual adjustments are needed.
Cubic Feet per Minute (airflow).
A condition that allows the line voltage input to the power supply to drop to
below the minimum operating voltage.
A power supply, after detecting a fault condition, shuts itself off. Even if the
fault condition disappears, the supply does not restart unless manual or
electronic intervention occurs. Manual intervention commonly includes
briefly removing and then reconnecting the supply, or it could be done
through a switch. Electronic intervention could be done by electronic
signals in the Server System.
A waveform changes from one level to another in a steady fashion, without
intermediate retracement or oscillation.
The periodic or random signals over frequency band of 0 Hz to 20 MHz.
A condition in which a supply attempts to provide more output current than
the amount for which it is rated. This commonly occurs if there is a "short
circuit" condition in the load attached to the supply.
Power Factor Corrected.
The periodic or random signals over a frequency band of 0 Hz to 20 MHz.
Rise time is defined as the time it takes any output voltage to rise from
10% to 95% of its nominal voltage.
The condition where the AC line voltage drops below the nominal voltage
conditions.
The condition where the AC line voltage rises above nominal voltage.
An output voltage that is present whenever AC power is applied to the AC
inputs of the supply.
Mean time between failure.
A typical logic level output signal provided by the supply that signals the
Server System that all DC output voltages are within their specified range.
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ERP2U Power Supply Design Guide, V2.31
4 Mechanical Overview
STATUS
Required (Optional)
The ERP2U is a power sub-system made up of a cage and redundant, hot swappable power supply mod ules. A
mechanical drawing of the cage is shown below in
350mm. This cage is intended to be mounted in the system and not redundant or hot swappable. The exterior
face of the cage accepts hot swappable power supply modules. The cage distributes output power from the
modules to a wire harness. Cooling fans, EMI filtering, and IEC inlet connector(s) may be located in the modules
or cage.
400.0 +/- 1.0
400.0 / 350.0 +/-1.0
SIDE VIEW
Figure 1. Two depths are defined to the cage; 400mm and
30 MAX
HANDLE/LATCH
#6-32 THD
2 PLACES
15.0 +/- 0.5
61.8 +/- 0.5
96.0 +/- 0.5
6.0 +/- 0.5
#6-32 THD
4 PLACES
6.0 +/- 0.5
6.0 +/- 0.5
83.0 +/- 0.5
118.0 +/- 1.0
113.0 +/- 0.5
MODULE
ACCESS
56.8 +/- 1.0
108.0 +/- 0.5
FRONT VIEWREAR VIEW
Figure 1: Enclosure Drawing
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ERP2U Power Supply Design Guide, V2.31
4.1 Acoustic Requirements
STATUS
Recommended
It is recommended the power supplies have a variable speed fan based on temperature and loading conditions.
There are three different acoustic sound power levels defined at different ambient temperatures and loading
conditions.
Table 1 Recommended Acoustic Sound Power Levels
Idle Typical Max
Ambient Temperature 28ºC 28ºC 45ºC
% Loading 30% 60% 100%
Sound Power (BA) 5.2 5.6 6.1
4.2 Airflow Requirements
STATUS
Recommended
The air shall exit the power supply on the AC inlet face. The power supply shall meet all requirements with the
below system airflow impedance presented to the power supplies airflow path.
Figure 2 System Airflow Impedance
System Flow Impedance - 2U
0.6
O)
0.5
2
0.4
0.3
0.2
0.1
System Pressure ( i n H
0.0
0 5 10 15 20
Power Supply Ai rflow (CFM)
4.3 Temperature Requirements
STATUS
Recommended
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ERP2U Power Supply Design Guide, V2.31
The power supply shall operate within all specified limits over the T
through the power supply and not over the exterior surfaces of the power supply.
Table 2: Thermal Requirements
ITEM DESCRIPTION MIN MAX UNITS
T
op
T
non-op
The power supply must meet UL enclosure requirements for temperature rise limits. All sides of the power supply
with exception of the air exhaust side, must be classified as “Handle, knobs, grips, etc. held for short periods of
time only”.
Operating temperature range. 0 50
Non-operating temperature range. -40 70
5 AC Input Requirements
STATUS
Required
The power supply modules shall incorporate universal power input with active power factor co rrection, which shall
reduce line harmonics in accordance with the EN61000-3-2 and JEIDA MITI standard s.
temperature range. All airflow shall pass
op
°C
°C
5.1 AC Inlet Connector
STATUS
Required
The AC input connector shall be an IEC 320 C-14 power inlet. This inlet is rated for 15 A/250 VAC. This
connector may be located on the module or on the cage.
5.2 Redundant AC Inlets
STATUS
Recommended
The power supply assembly may have dual redundant AC inlets. The power supply shall be able to operate over
its full, specified range of requirements with either or both AC input powered. If there is a loss of one AC inlet the
power supplies shall continue to operate with no interruption of performance. It is required that all redundant
power supply modules be present to support redundant AC inlets.
5.3 AC Input Voltage Specification
STATUS
Required
The power supply must operate within all specified limits over the following input voltage range. Harmonic
distortion of up to 10% THD must not cause the power supply to go out of specified limits. The power supply shall
operate properly at 85 VAC input voltage to guarantee proper design margins.
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Table 3: AC Input Rating
PARAMETER MIN RATED MAX
Voltage (110) 90 V
Voltage (220) 180 V
Frequency 47 Hz 63 Hz
5.4 Input Under Voltage
STATUS
Required
The power supply shall contain protection circuitry such that application of an input voltage below the minimum
specified in section
5.3 shall not cause damage to the power supply.
5.5 Efficiency
rms
rms
100-127 V
200-240 V
rms
rms
140 V
264 V
rms
rms
STATUS
Recommended/Required
The following table provides recommended and required minimum efficiency levels. These are provided at three
different load levels; 100%, 50% and 20%. The “required” minimum efficiency levels are for the purpose of proper
power supply cooling when installed in the system. The “recommended” minimum efficiency levels are for the
purpose of reducing the system’s AC power consumpt ion. The efficiency is specified at 50% and 20% loading
conditions to help reduce system power consumption at typical system loading conditions.
Efficiency shall be tested at AC input voltages of 115VAC and 230VAC. Refer to
www.efficientpowersupplies.org
for details on proper efficiency testing methods.
Table 4: Efficiency
Loading 100% of maximum 50% of maximum 20% of maximum
Required minimum 70% 72% 65%
Recommended minimum 80% 83% 78%
5.6 AC Line Dropout
STATUS
Required
An AC line dropout is defined to be when the AC input drops to 0 VAC at any phase of the AC line for any length
of time. During an AC dropout of one cycle or less the power supply must meet dynamic voltage regulation
requirements up to 75% of the rated output load. An AC line dropout of one cycle or less shall not cause any
tripping of control signals or protection circuits. If the AC dropout lasts longer than one cycle or the load is greater
than 75%, the power supply should recover and meet all turn on requirements. The power supply must meet the
AC dropout requirement over rated AC voltages, frequencies, and output loading conditions. Any dropout of the
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ERP2U Power Supply Design Guide, V2.31
AC line shall not cause damage to the power supply. In the case of redundant AC inputs, the AC line dropout
may occur on either or both AC inlet.
5.7 AC Line Fuse
STATUS
Required
The power supply shall incorporate one input fuse on the LINE side for input over-current protection to prevent
damage to the power supply and meet product safety requirements. Fuses should be slow blow type or
equivalent to prevent nuisance trips. AC inrush current shall not cause the AC line fuse to blow under any
conditions. All protection circuits in the power supply shall not cause the AC fuse to blow unless a component in
the power supply has failed. This includes DC output load short conditions.
5.8 AC Inrush
STATUS
Required
The power supply must meet inrush requirements for any rated AC voltage, during turn on at any phase of AC
voltage, during a single cycle AC dropout condition, during repetitive ON/OFF cycling of AC, and over the
specified temperature range (T
(including input fuse, bulk rectifiers, and surge limiting device).
). The peak inrush current shall be less than the ratings of its critical components
op
STATUS
Recommended
An additional inrush current limit is recommended for some system applications that require multiple systems on a
single AC circuit. AC line inrush current shall not exceed 40 A peak. After one-quarter of the AC cycle, the input
current should be no more than the specified maximum input current from
Table 3.
5.9 AC Line Transient Specification
STATUS
Recommended
AC line transient conditions shall be defined as “sag” and “surge” conditions. Sag conditions (also referred to as
“brownout” conditions) will be defined as the AC line voltage dropping below nominal voltage. Surge conditions
will be defined as the AC line voltage rising above nominal voltage.
The power supply shall meet the requirements under the following AC line sa g and surge conditions.
Table 5: AC Line Sag Transient Performance
AC Line Sag
Duration Sag Operating AC Voltage Line Frequency Performance Criteria
Continuous 10% Nominal AC Voltage ranges 50/60 Hz No loss of function or performance
0 to 1 AC
cycle
100% Nominal AC Voltage ranges 50/60 Hz No loss of function or performance
>1 AC cycle >10% Nominal AC Voltage ranges 50/60 Hz Loss of function acceptable, self
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recoverable
Table 6: AC Line Surge Transient Performance
AC Line Surge
Duration Surge Operating AC Voltage Line Frequency Performance Criteria
Continuous 10% Nominal AC Voltages 50/60 Hz No loss of function or performance
0 to ½ AC
cycle
30% Mid-point of nominal AC
Voltages
50/60 Hz No loss of function or performance
5.10 AC Line Fast Transient Specification
STATUS
Recommended
The power supply shall meet the EN61000-4-5 directive and any additional requirements in IEC1000-4-5:1995
and the Level 3 requirements for surge-withstand capability, with the following conditions and exceptions:
• These input transients must not cause any out-of-regulation conditions, such as overshoot and
undershoot, nor must it cause any nuisance trips of any of the power supply protection circuits.
• The surge-withstand test must not produce damage to the power supply.
• The supply must meet surge-withstand test conditions under maximum and minimum DC-output load
conditions.
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ERP2U Power Supply Design Guide, V2.31
6 DC Output Specification
These are the output requirements for the power supply assembly including cage and module.
6.1 Output Connectors
The power supply distribution board shall have one of the two following output connector and wire harness
configurations, depending upon the type of 12V rail configuration needed by the system.
6.1.1 Required Baseboard power connector
STATUS
Required
Connector housing: 24-Pin Molex 39-01-2240 or equivalent
Contact: Molex
Pin Signal 18 AWG Color Pin Signal 18 AWG Color
1 +3.3 VDC Orange 13 +3.3 VDC Orange
44476-1111 or equivalent
Table 7: P1 Baseboard Power Connector
2 +3.3 VDC Orange 14 -12 VDC Blue
3 COM Black 15 COM Black
4 +5 VDC Red 16 PS_ON Green
5 COM Black 17 COM Black
6 +5 VDC Red 18 COM Black
7 COM Black 19 COM Black
8 PWR OK Gray 20 Reserved (-5 V in
ATX)
9 5 VSB Purple 21 +5 VDC Red
10 +12 V3 Yellow 22 +5 VDC Red
11 +12 V3 Yellow 23 +5 VDC Red
12 +3.3 VDC Orange 24 COM Black
If 240VA limiting is not a requirement for the power supply than all +12V outputs are common and may have the same wire
color (yellow).
Table 8: Processor Power Connector
Pin Signal 18 AWG color Pin Signal 18 AWG Color
1 COM Black 5 +12 V1 Yellow/Black Stripe
N.C.
2 COM Black 6 +12 V1 Yellow/Black Stripe
3 COM Black 7 +12 V2 Yellow
4 COM Black 8 +12 V2 Yellow
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ERP2U Power Supply Design Guide, V2.31
If 240VA limiting is not a requirement for the power supply than all +12V outputs are common and may have the same wire
color (yellow).
6.1.2 +12V4 Baseboard Power Connector
STATUS
Required for 700W, 750W and 800W power levels
Systems that require more then 16A of +12V current to the baseboard will require this additional 2x2 power
connector. This is due to the limited +12V capability of the 2x12 baseboard power connector. +12V4 will power
this 2x2 connector.
Pin Signal 18 AWG color Pin Signal 18 AWG Color
1 COM Black 3 +12 V4 Yellow/Green Stripe
2 COM Black 4 +12 V4 Yellow/Green Stripe
If 240VA limiting is not a requirement for the power supply than all +12V outputs are common and may have the same wire
color (yellow
6.1.3 Required Peripheral Power Connectors
Connector housing: Amp 1-480424-0 or equivalent
Contact: Amp 61314-1 contact or equivalent
Table 9: Peripheral Power Connectors
Pin Signal 18 AWG Color
1 +12V4 Yellow
2 COM Black
3 COM Black
4 +5 VDC Red
1. If 240VA limiting is not a requirement for the power supply than all +12V outputs are common and may have the same
wire color.
6.1.4 Required Floppy Power Connector
Connector housing: Amp 171822-4 or equivalent
Table 10: P9 Floppy Power Connector
Pin Signal 22 AWG Color
1 +5 VDC Red
2 COM Black
3 COM Black
4 +12V4 Yellow
1. The +12V power to peripherals may be split between the second, third, or fou rth +12V channel for the purpose of
limiting power to less than 240VA.
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2. If 240VA limiting is not a requirement for the power supply than all +12V outputs are common and may have the same
wire color.
6.1.5 Serial ATA Power Connector
STATUS
Optional
This is a required connector for systems with serial ATA devices.
The detailed requirements for the serial ATA connector can be found in the “Serial ATA : High Speed Serialized
AT Attachment “ specification at
Molex Housing #675820000
Molex Terminal #67510000
Pin Signal 18 AWG Color
5 +3.3VDC Orange
4 COM Black
3 +5VDC Red
2 COM Black
1 +12V4 Yellow/Green Stripe
www.serialata.org.
Table 11: Floppy Power Connector
Serial ATA Connector
5
4
3
2
1
6.1.6 Server Signal Connector
STATUS
Optional
For server systems with SMBus features, the power supply may have an additional connector, which pro vides
serial SMBus for FRU data and remote sense on 3.3V and Return. If the Server Signal connector is not present,
the 3.3V remote sense will be double crimped into one of the 3.3V power contacts in the Baseboard power
connector.
Connector housing: 5-pin Molex 50-57-9405 or equivalent
Contacts: Molex 16-02-0088 or equivalent
Table 12: Server Signal Connector
Pin Signal 24 AWG Color
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ERP2U Power Supply Design Guide, V2.31
1 SMBus Clock White/Green Stripe
2 SMBus Data White/Yellow Stripe
3 SMBAlert
4 ReturnS Black/White Stripe
5 3.3RS Orange/White Stripe
6.2 Grounding
STATUS
Required
The ground of the pins of the power assembly wire harness provides the power return path. The wire harn ess
ground pins shall be connected to safety ground (power supply enclosure).
6.3 Remote Sense
STATUS
Optional
The power assembly may have remote sense for the +3.3V (3.3VS) and return (ReturnS) if the Optional Server
Signal connector is implemented and the module has a +3.3V output. The remote sense return (ReturnS) is used
to regulate out ground drops for all output voltages. The +3.3V remote sense (3.3VS) is used to regulate out
drops in the system for the +3.3 V output. The remote sense input impedance to the power sub-assembly must
be greater than 200 ohms on 3.3 VS and ReturnS. This is the value of the resistor connecting the remote sense
to the output voltage internal to the power assembly. Remote sense must be able to regulate out a minimum of
200 mV drop on the +3.3 V output. The remote sense return (ReturnS) must be able to regulate out a minimum of
200 mV drop in the power ground return. The current in any remote sense line shall be 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 assembly’s output connector to the remote sense points.
6.4 Output Power/Currents
STATUS
Recommended
The following tables define the power and current ratings for different recommended power levels. Depending
upon the system design, the power supply modules may have less outputs than required by the system (example:
+12V and 5VSB). If there are less outputs than required by the system on the module, the cage shall have
additional DC/DC converters to generate the voltages not produced by the modules (example: +12V/+5V,
+12V/+3.3V, +12V/-12V). The combined output power of all outputs from the cage shall not exceed the rated
output power. The power assembly shall meet both static and dynamic voltage regulation requirements over the
full load ranges. The power sub-assembly shall supply redundant power over the full load ranges.
Table 13: 550 W Load Ratings
Voltage Minimum Continuous Maximum Continuous Peak
7
+3.3 V
7
+5 V
0.8 A 24 A
0.5 A 24 A
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+12V1 0 A 16 A 18 A
+12V2 0 A 16 A 18 A
+12V3 0.9 A 14 A
+12V4 0.1 A 8 A 13 A
-12 V 0 A 0.5 A
+5 VSB 0.1 A 2.0 A
1. Maximum continuous total DC output power should not exceed 550 W.
2. Maximum continuous combined load on +3.3 VDC and +5 VDC outputs shall not exceed 140 W.
3. Maximum Peak total DC output power should not exceed 630 W.
4. Peak power and current loading shall be supported for a minimum of 10 second.
5. Maximum combined current for the 12 V outputs shall be 38 A.
6. Maximum 12V combined peak current shall be 45 A.
7. The 3.3V and 5V may be supply by the module or DC/DC converters powered from +12V in the cage.
Table 14: 600 W Load Ratings
Voltage Minimum Continuous Maximum Continuous Peak
7
+3.3 V
7
+5 V
+12V1 0 A 16 A 18 A
+12V2 0 A 16 A 18 A
+12V3 0.9 A 14 A
+12V4 0.1 A 8 A 13 A
-12 V 0 A 0.5 A
+5 VSB 0.1 A 2.0 A
1. Maximum continuous total DC output power should not exceed 600 W.
2. Maximum continuous combined load on +3.3 VDC and +5 VDC outputs shall not exceed 140 W.
3. Maximum peak total DC output power should not exceed 710 W.
4. Peak power and current loading shall be supported for a minimum of 10 second.
5. Maximum combined current for the 12 V outputs shall be 42 A.
6. Peak current for the combined 12 V outputs shall be 51 A.
7. The 3.3V and 5V may be supply by the module or DC/DC converters powered from +12V in the cage.
0.8 A 24 A
0.5 A 24 A
Table 15: 650 W Load Ratings
Voltage Minimum Continuous Maximum Continuous Peak
7
+3.3 V
7
+5 V
+12V1 0 A 16 A 18 A
+12V2 0 A 16 A 18 A
+12V3 0.9 A 14 A
+12V4 0.1 A 8 A 13 A
-12 V 0 A 0.5 A
+5 VSB 0.1 A 2.0 A
1. Maximum continuous total DC output power should not exceed 650 W.
2. Maximum continuous combined load on +3.3 VDC and +5 VDC outputs shall not exceed 140 W.
3. Maximum Peak total DC output power should not exceed 770 W.
0.8 A 24 A
0.5 A 24 A
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4. Peak power and current loading shall be supported for a minimum of 10 second.
5. Maximum combined current for the 12 V outputs shall be 45 A.
6. Maximum 12V combined peak current shall be 54 A.
7. The 3.3V and 5V may be supply by the module or DC/DC converters powered from +12V in the cage.
ERP2U Power Supply Design Guide, V2.31
Table 16: 700 W Load Ratings
Voltage Minimum Continuous Maximum Continuous Peak
7
+3.3 V
7
+5 V
+12V1 0 A 16 A 18 A
+12V2 0 A 16 A 18 A
+12V3 0.9 A 16 A 18 A
+12V4 0.1 A 16 A 18 A
-12 V 0 A 0.5 A
+5 VSB 0.1 A 3.0 A 3.5 A
1. Maximum continuous total DC output power should not exceed 700 W.
2. Maximum continuous combined load on +3.3 VDC and +5 VDC outputs shall not exceed 170 W.
3. Maximum Peak total DC output power should not exceed 780 W.
4. Peak power and current loading shall be supported for a minimum of 10 second.
5. Maximum combined current for the 12 V outputs shall be 56 A.
6. Maximum 12V combined peak current shall be 62 A.
7. The 3.3V and 5V may be supply by the module or DC/DC converters powered from +12V in the cage.
0.8 A 24 A
0.5 A 30 A
Table 17: 750 W Load Ratings
Voltage Minimum Continuous Maximum Continuous Peak
7
+3.3 V
7
+5 V
+12V1 0 A 16 A 18 A
+12V2 0 A 16 A 18 A
+12V3 0.9 A 16 A 18 A
+12V4 0.1 A 16 A 18 A
-12 V 0 A 0.5 A
+5 VSB 0.1 A 3.0 A 3.5 A
1. Maximum continuous total DC output power should not exceed 750 W.
2. Maximum continuous combined load on +3.3 VDC and +5 VDC outputs shall not exceed 170 W.
3. Maximum Peak total DC output power should not exceed 830 W.
4. Peak power and current loading shall be supported for a minimum of 10 second.
5. Maximum combined current for the 12 V outputs shall be 60 A.
6. Maximum 12V combined peak current shall be 66 A.
7. The 3.3V and 5V may be supply by the module or DC/DC converters powered from +12V in the cage.
0.8 A 24 A
0.5 A 30 A
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Table 18: 800 W Load Ratings
Voltage Minimum Continuous Maximum Continuous Peak
7
+3.3 V
7
+5 V
+12V1 0 A 16 A 18 A
+12V2 0 A 16 A 18 A
+12V3 0.9 A 16 A 18 A
+12V4 0.1 A 16 A 18 A
-12 V 0 A 0.5 A
+5 VSB 0.1 A 3.0 A 3.5 A
1. Maximum continuous total DC output power should not exceed 800 W.
2. Maximum continuous combined load on +3.3 VDC and +5 VDC outputs shall not exceed 170 W.
3. Maximum Peak total DC output power should not exceed 880 W.
4. Peak power and current loading shall be supported for a minimum of 10 second.
5. Maximum combined current for the 12 V outputs shall be 64 A.
6. Maximum 12V combined peak current shall be 70 A.
7. The 3.3V and 5V may be supply by the module or DC/DC converters powered from +12V in the cage.
0.8 A 24 A
0.5 A 30 A
6.4.1 Standby Outputs
STATUS
Required
The 5 VSB output shall be present when an AC input greater than the power supply turn on voltage is applied.
6.4.2 Fan operation in standby mode
STATUS
Required
For standby output at the higher power level, when the supply is in standby mode it is required that the power
supply fan(s) remain running at a very low speed. This helps prevent power supply overheating when many
systems in the same rack are in standby mode. Running the fan(s) in standby mode also allows better cooling to
the standby power converter.
6.5 Voltage Regulation
STATUS
Required
The power assembly 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/noi se specified in Section
outputs are measured with reference to the return remote sense (ReturnS) signal. The 5 V, 12V1, 12V2, 12V3,
12V4, –12 V and 5 VSB outputs are measured at the power assembly connectors referenced to ReturnS. The
+3.3 V is measured at its remote sense signal (3.3VS) located at the signal connector.
5.10. All
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Table 19: Voltage Regulation Limits
Parameter MIN NOM MAX Units Tolerance
+3.3 V +3.14 +3.30 +3.47 V
+5 V +4.75 +5.00 +5.25 V
+12V1,2,3,4 +11.40 +12.00 +12.60 V
-12 V -10.80 -12.20 -13.20 V
+5 VSB +4.75 +5.00 +5.25 V
rms
rms
rms
rms
rms
STATUS
Optional
Some system applications may require tighter regulation limits on the outputs. The optional regulation limits are
shown below.
Table 20: Optional +5V Regulation Limits
Parameter MIN NOM MAX Units Tolerance
+3.3V +3.20 +3.30 +3.47 V
+5 V +4.85 +5.00 +5.25 V
+12V1,2,3,4 +11.64 +12.00 +12.60 V
-12V -11.40 -12.00 -13.08 V
+5 VSB +4.85 +5.00 +5.25 V
rms
rms
rms
rms
rms
+/-5%
+/-5%
+/-5%
+/-10%
+/-5%
+5/-3%
+5/-3%
+5/-3%
+9/-5%
+5/-3%
6.6 Dynamic Loading
STATUS
Required
The output voltages shall remain within the limits specified in Error! Reference source not found. for the step
loading and within the limits specified in
Table 22 for the capacitive loading specified in 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 range.
Table 21: Transient Load Requirements
Output
+3.3 V 30% of max load
+5 V 30% of max load
12V1+12V2+12V3+12V4 65% of max load
+5 VSB 25% of max load
Δ Step Load Size
Load Slew Rate Capacitive Load
0.5 A/μs 1000 μF
0.5 A/μs 1000 μF
0.5 A/μs 2200 μF
0.5 A/μs 1 μF
6.7 Capacitive Loading
STATUS
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Required
The power supply shall be stable and meet all requirements, except dynamic loading requirements, with the
following capacitive loading ranges.
Note: Up to 10,000 μF of the +12V capacitive loading may be on the +12V1 output.
Table 22: Capacitve Loading Conditions
Output MIN MAX Units
+3.3 V 10 12,000
+5 V 10 12,000
+12 V 10 11,000
-12 V 1 350
+5 VSB 1 350
6.8 Ripple / Noise
STATUS
Required
μF
μF
μF
μF
μF
The maximum allowed ripple/noise output of the power supply is defined in Table 24. This is measured over a
bandwidth of 0 Hz to 20 MHz at the power supply output connectors. A 10 μF tantalum capacitor in parallel with a
0.1 μF ceramic capacitor are placed at the point of measurement.
Table 23: Ripple and Noise
+3.3 V +5 V +12 V -12 V +5 VSB
50 mVp-p 50 mVp-p 120 mVp-p 120 mVp-p 50 mVp-p
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6.9 Redundancy
The power sub-system may have different levels of redundancy depending upon the availability requirements of
the system. The Required, Recommended, and Optional items are broken down here. To be redundant each
item must be in the hot swap power supply module.
STATUS
Required
The power sub-system shall have redundancy of the main power converters for the power factor correction stage
and the main +12V output.
STATUS
Recommended
It is recommended the power sub-system have redundancy for the following items, however, depending upon the
system availability requirements, these items may be non-redundant.
It is recommended to have redundancy for the output or’ing devices, fans, AC bridge, output capacitors, -12V
converter, and 5VSB converter.
STATUS
Optional
It is optional to have redundancy for the AC EMI filter components, 3.3V output converter, and 5V output
converter.
6.10 Hot Swap Requirements
STATUS
Required
The power supply modules shall be hot swappable. Hot swapping a power supply is the process of inserting and
extracting a power supply from an operating power system. During this process the output voltages shall remain
within the limits specified in
conducted when the sub-system is operating under both static and dynamic conditions. The sub-system shall not
exceed the maximum inrush current as specified in section
following methods:
• • AC connecting separately to each module. Up to two power supplies may be on a single AC power source.
Extraction: The AC power will be disconnected from the power supply first and then the power supply is
extracted from the sub-system. This could occur in standby mode or powered on mode. Insertion: The
module is inserted into the cage and then AC power will be connected to the power supply module.
For power modules with AC docking at the same time as DC. Extraction: The module is extracted from the
cage and both AC and DC disconnect at the same time. This could occur in standby or power on mode. No
damage or arcing shall occur to the DC or AC contacts which could cause damage. Insertion: The AC and
DC connect at the same time as the module is inserted into the cage. No damage to the connector contacts
shall occur. The module may power on or come up into standby mode.
Table 20 with the capacitive load specified Table 23. The hot swap test must be
5.8. The power supply can be hot swapped by the
Many variations of the above are possible. Supplies need to be compatible with these different variations
depending upon the sub-system construction. In general, a failed (off by internal latch or external control) supply
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ERP2U Power Supply Design Guide, V2.31
may be removed, then replaced with a good power supply, however, hot swap needs to work with operational as
well as failed power supplies. The newly inserted power supply may get turned on by inserting the supply into the
system or by system management recognizing an inserted supply and explicitly turning it on.
6.11 Timing Requirements
STATUS
Required
These are the timing requirements for the power assembly operation. The output voltages must rise from 10% to
within regulation limits (T
rise at about the same time. All outputs must rise monotonically. The +5 V output needs to be greater than the
+3.3 V output during any point of the voltage rise. The +5V output must never be greater than the +3.3V output
by more than 2.25 V. Each output voltage shall reach regulation within 50 ms (T
on of the power supply. Each output voltage shall fall out of regulation within 400 ms (T
during turn off.
Figure 3 and Figure 4 show the turn ON and turn OFF timing requirements. In Figure 4, the
timing is shown with both AC and PSON# controlling the ON/OFF of the power supply.
Item Description MIN MAX Units
T
vout_rise
T
vout_on
T
vout_off
Output voltage rise time from each main output. 5 200 ms
All main outputs must be within regulation of each
other within this time.
All main outputs must leave regulation within this
time.
) within 5 to 200ms. The +3.3 V, +5 V and +12 V output voltages should start to
vout_rise
) of each other during turn
vout_on
) of each other
vout_off
Table 24: Output Voltage Timing
50 ms
400 ms
V
V1
10% Vout
V2
V3
T
vout_rise
T
vout_on
T
vout_off
Figure 3: Output Voltage Timing
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Table 25: Turn On/Off Timing
Item Description MIN MAX UNITS
T
sb_on_delay
T
ac_on_delay
T
vout_holdup
T
pwok_holdup
T
pson_on_delay
T
pson_pwok
T
pwok_on
T
pwok_off
T
pwok_low
T
sb_vout
Delay from AC being applied to 5 VSB being
1500 ms
within regulation.
Delay from AC being applied to all output voltages
2500 ms
being within regulation.
Time all output voltages stay within regulation
18 ms
after loss of AC.
Delay from loss of AC to deassertion of PWOK. 17 ms
Delay from PSON# active to output voltages within
5 400 ms
regulation limits.
Delay from PSON# deactive to PWOK being
50 ms
deasserted.
Delay from output voltages within regulation limits
100 500 ms
to PWOK asserted at turn on.
Delay from PWOK deasserted to output voltages
1 ms
(3.3 V, 5 V, 12 V, -12 V) dropping out of regulation
limits.
Duration of PWOK being in the deasserted state
100 ms
during an off/on cycle using AC or the PSON#
signal.
Delay from 5 VSB being in regulation to O/Ps
50 1000 ms
being in regulation at AC turn on.
STATUS
Recommended
Item Description MIN MAX UNITS
T
vout_holdup
T
pwok_holdup
T
sb_holdup
Time all output voltages stay within regulation
21 ms
after loss of AC.
Delay from loss of AC to deassertion of PWOK. 20 ms
Time 5VSB output voltage stays within regulation
70 ms
after loss of AC.
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ERP2U Power Supply Design Guide, V2.31
PWOK
5VSB
PSO
T
sb_on_delay
N#
T
AC_on_delay
T
sb_vout
AC turn on/off cycle
T
pwok_on
T
pwok_holdup
T
vout_holdup
Tsb_holdup
T
pwok_off
T
pwok_low
T
T
pwok_on
T
pson_on_delay
PSON turn on/off cycle
T
T
pson_pwok
pwok_off
Figure 4: Turn On/Off Timing
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7
Protection Circuits
STATUS
Required
Protection circuits inside the power supply shall cause only the power supply’s main outputs to shutdown. If the
power supply latches off due to a protection circuit tripping, an AC cycle OFF for 15 s and a PSON
for 1 s must be able to reset the power supply.
#
cycle HIGH
7.1 Current Limit
STATUS
Required
The power supply shall have current limit to prevent the +3.3 V, +5 V, and +12 V outputs from exceeding the
values shown in
latch will be cleared by toggling the PSON
damaged from repeated power cycling in this condition. -12 V and 5 VSB shall be protected under over current or
shorted conditions so that no damage can occur to the power supply.
Table 27. If the current limits are exceeded, the power supply shall shutdown and latch off. The
Voltage Ov er Current Limit (Iout limit)
+3.3 V 110% minimum; 150% maximum
+5 V 110% minimum; 150% maximum
+12V (combined) Peak combine current minimum; 150% maximum
#
signal or by an AC power interruption. The power supply shall not be
Table 26: Over Current Protection
7.2 240VA Protection
STATUS
Recommended
System designs may require user access to energized areas of the system. In these cases the power supply may
be required to meet regulatory 240VA energy limits for any power rail. Since the +12V rail combined power
exceeds 240VA it must be divided into separate channels to meet this requirement. Each separate rail needs to
be limited to less than 20A for each +12V rail. The separate +12V rails do not necessarily need to be
independently regulated outputs. They can share a common power conversion stage.
Table 27: Over Current Protection
Voltage Over Current Limit (Iout limit)
+3.3 V 110% minimum; 150% maximum
+5 V 110% minimum; 150% maximum
+12V1,2,3,4 Peak current minimum; 20A maximum
1. Peak currents shall be maintained for a minimum of 500msec. The maximum duration of the peak current exceeding the
240VA limit should be limited to meet safety regulations. A maximum duration of 1 second is recommended.
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7.3 Over Voltage Protection
STATUS
Required
The power supply over voltage protection shall be locally sensed in the hot swap modules. The power supply
shall shutdown and latch off after an over voltage condition occurs. This latch shall be cleared by toggling the
#
PSON
measured at the output of the power supply’s connectors. The voltage shall never exceed the maximum levels
when measured at the power pins of the power supply connector during any single point of fail. The voltage shall
never trip any lower than the minimum levels when measured at the power pins of the power supply connector.
signal or by an AC power interruption. Table 29 contains the over voltage limits. The values are
Table 28: Over Voltage Limits
Output Voltage MIN (V) MAX (V)
+3.3 V 3.9 4.5
+5 V 5.7 6.5
+12V1,+12V2, +12V3, +12V4 13.3 14.5
-12 V -13.3 -14.5
+5 VSB 5.7 6.5
7.4 Over Temperature Protection
STATUS
Recommended
The power supply will be protected against over temperature conditions caused by loss of fan cooling or
excessive ambient temperature. In an OTP condition the PSU will shutdown. When the power supply
temperature drops to within specified limits, the power supply shall restore power automatically. The OTP circuit
must have built in hysteresis such that the power supply will not oscillate on and off due to temperature recovering
condition. The OTP trip level shall have a minimum of 4 °C of ambient temperature hysteresis.
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8 Control and Indicator Functions
The following sections define the input and output signals from the power supply.
Signals that can be defined as low true use the following convention:
#
signal
= low true
8.1 PSON#
STATUS
Required
The PSON# signal is required to remotely turn on/off the power supply. PSON# is an active low signal that turns
on the +3.3 V, +5 V, +12 V, and -12 V power rails. When this signal is not pulled low by the system, or left open,
the outputs (except the +5 VSB and Vbias) turn off. This signal is pulled to a standby voltage by a pull-up resistor
internal to the power supply. Refer to
Signal Type
PSON# = Low
PSON# = Open or High
Figure 4 for timing diagram.
#
Table 29: PSON
Signal Characteristic
Accepts an open collector/drain input from the system.
Pull-up to VSB located in power supply.
ON
OFF
MIN MAX
Logic level low (power supply ON)
Logic level high (power supply OFF)
Source current, Vpson = low
Power up delay: T
PWOK delay: T
pson_on_delay
pson_pwok
0 V 1.0 V
2.0 V 5.25 V
4 mA
5 ms 400 ms
50 ms
Disabled
Hysteresis ≥ 0.3V and/or other de-bounce method
≤ 1.0 V
PS is
enabled
≥ 2.0 V
PS is
disabled
Enabled
0V
1.0V
2.0V
5.25V
Figure 5: PSON# Signal Characteristics
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8.2 PWOK (Power OK)
STATUS
Required
PWOK is a power OK signal and will be pulled HIGH by the power supply to indicate that all the outputs are within
the regulation limits of the power supply. When any output voltage falls below regulation limits or when AC power
has been removed for a time sufficiently long so that power supply operation is no longer guaranteed, PWOK will
be deasserted to a LOW state. See
start of the PWOK delay time shall be inhibited as long as any power supply output is in current limit.
Signal Type
PWOK = High
PWOK = Low
Logic level low voltage, Isink = 4 mA
Logic level high voltage, Isource=200 μA
PWOK delay: T
PWOK rise and fall time
Power down delay: T
pwok_on
Figure 4 for a representation of the timing characteristics of PWOK. The
Table 30: PWOK Signal Characteristics
+5V TTL Compatible output signal
Power OK
Power Not OK
MIN MAX
0 V 0.4 V
2.4 V 5.25 V
200 ms 1000 ms
pwok_off
1 ms
100 μs
8.3 SMBus Communication
STATUS
Optional
The serial bus communication devices for PSMI and FRU data in the power supply shall be compatible with both
SMBus 2.0 ‘high power’ and I
signaling. The SMBus pull-ups are located on the motherboard and may be connected to 3.3V or 5V.
Two pins are allocated on the power supply. One pin is the Serial Clock (PSM Clock). The second pin is used for
Serial Data (PSM Data). Both pins are bi-directional and are used to form a serial bus. The device(s) in the
power supply shall be located at an address(s) determined by addressing pins A0 and A1 on the power supply
module. The circuits inside the power supply shall derive their power from the 5VSB bus. Device(s) shall be
powered from the system side of the 5VSB or’ing device. No pull-up resistors shall be on SCL or SDA inside the
power supply. These pull-up resistors should be located external to the power supply.
2
C Vdd based power and drive. This bus shall operate at 3.3V but tolerant of 5V
8.4 Power Supply Management Interface
STATUS
Optional
The PSMI device in the power supply shall derive its power off of the 5VSB output on the system side of the or’ing
device and grounded to ReturnS. It shall be located at an address set by the A0 and A1 pins. Refer to the PSMI
specification posted on the
requirements. PSMI is a SMBus interface used to communicate power management information to the system.
www.ssiforum.org website for details on the Power Supply Monitoring Interface
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PDB addressing A0/A1 0/0 0/1 1/0 1/1
Power supply PSMI device B0h B2h B4h B6h
8.5 Field Replacement Unit (FRU) Signals
STATUS
Optional
The FRU device in the power supply shall derive its power off of the 5VSB output on the system side of the or’ing
device and grounded to ReturnS. The Write Control (or Write protect) pin should be tied to ReturnS inside the
power supply so that information can be written to the EEPROM.
PDB addressing A0/A1 0/0 0/1 1/0 1/1
Power supply IPMI FRU device A0h A2h A4h A6h
Power supply PSMI device B0h B2h B4h B6h
8.5.1 Module FRU Data
FRU data shall be stored starting in address location 8000h through 80FFh. The FRU data format shall be
compliant with the IPMI specifications. The current versions of these specifications are available at:
http:\\developer.intel.com/design/servers/ipmi/spec.htm.
8.5.2 Module FRU Data Format
The information to be contained in the FRU device is shown in the following table.
Table 31: FRU Device Information
Area Type Description
Common Header As defined by the FRU document
Internal Use Area Not required, do not reserve
Chassis Info Area Not applicable, do not reserve
Board Info Area Not applicable, do not reserve
8.5.2.1 Product Info Area
Implement as defined by the IPMI FRU document. Product information shall be defined as follows:
Table 32: FRU Device Product Information Area
Field Name Field Description
Manufacturer Name {Formal name of manufacturer}
Product Name {Manufacturer’s model number}
Product part/model number Customer part number
Product Version Customer current revision
Product Serial Number {Defined at time of manufacture}
Asset Tag {Not used, code is zero length byte}
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FRU File ID {Not required}
PAD Bytes {Added as necessary to allow for 8-byte offset to next area}
8.5.2.2 MultiRecord Area
Implement as defined by the IPMI FRU document. The following record types shall be used on this power supply:
• Power Supply Information (Record Type 0x00)
• DC Output (Record Type 0x01)
• No other record types are required for the power supply.
MultiRecord information shall be defined as follows:
Table 33: FRU Device Product Information Area
Field Name (PS Info) Field Information Definition
Overall Capacity (watts) 480
Peak VA 550
Inrush current (A) 50
Inrush interval (ms) 5
Low end input voltage range 1 90
High end input voltage range 1 140
Low end input voltage range 2 180
High end input voltage range 2 264
A/C dropout tol. (ms) 20
Binary flags Set for: Hot Swap support, Autoswitch, and PFC
Peak Wattage
Set for: 10 s, 550 W
Combined wattage Set for 5 V & 3.3V combined wattage of 115 W
Predictive fail tach support Not supported, 00h value
Field Name (Output) Field Description:
Five outputs are to be defined from #1 to #5, as follows: +3.3 V, +5
V, +12 V, -12V, and +5 VSB.
Output Information Set for: Standby on +5 VSB, No Standby on all others.
All other output fields Format per IPMI specification, using parameters in the EPS12V
specification.
8.6 LED Indicators
STATUS
Required
There shall be a single bi-color LED OR two LEDs, one AMBER and one GREEN, on each hot swap power
module to indicate power supply status. When AC is applied to the power supply and standby voltages are
available the GREEN LED shall BLINK. The GREEN LED shall turn ON to indicate that all the power outputs are
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available. The AMBER LED shall turn ON to indicate that the power supply has failed, shutdown due to over
current, or shutdown due to over temperature. Refer to
Table 34: LED Indicators
POWER SUPPLY CONDITION Power Supply LED(s)
AMBER GREEN
No AC power to all PSU OFF OFF
No AC power to this PSU only AMBER OFF
AC present / Only Standby Outputs On OFF BLINK
Power supply DC outputs ON and OK OFF ON
Table 35: LED Indicators for conditions of the LED(s).
Power supply failure (includes over
voltage, over temperature)
Current limit ON OFF
The LED(s) shall be visible on the power supply’s exterior face. The LED location shall meet ESD requirements.
LED shall be securely mounted in such a way that incidental pressure on the LED shall not cause it to become
displaced.
ON OFF
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9 MTBF
STATUS
Recommended
The power module shall have a minimum MTBF at continuous operation of 1) 50,000 hours at 100% load and
45 °C, as calculated by Bellcore RPP, or 2) 100,000 hours demonstrated at 100% load and 50 °C.
The power
45 °C, as calculated by Bellcore RPP, or 2) 400,000 hours demonstrated at 100% load and 50 °C
cage shall have a minimum MTBF at continuous operation of 1) 200,000 hours at 100% load and
10 Agency Requirements
STATUS
Recommended
The power supply must comply with all regulatory requirements for its intended geographical market. Depending
on the chosen market, regulatory requirements may vary. Although a power supply can be designed for
worldwide compliance, there may be cost factors that drive different versions of supplies for different
geographically targeted markets.
This specification requires that the power supply meet all regulatory requirements for the intended market at the
time of manufacturing. Typically this includes:
• UL
• CSA
• A Nordic CENELEC
• TUV
• VDE
• CISPR Class B
• FCC Class B
The power supply, when installed in the system, shall meet immunity requirements specified in EN55024.
Specific tests are to be EN61000-4-2 ,-3, -4, -5, -6, -8, -11, EN61000-3-2, -3, and JEIDI MITI standard. The
power supply must maintain normal performance within specified limits. This testing must be completed by the
system EMI engineer. Conformance must be designated with the European Union CE Marking. Specific
immunity level requirements are left to customer requirements.
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