ATX Version 3.0 Multi Rail Desktop Platform Power Supply

Design Guide

ID Date Version Classification
336521 02/01/2023 Public

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Document Table of Contents

Revision History

Document Number

Revision Number

Description

Revision Date

336521

0.5

  • Initial release of combined power supply design guide
  • Combined CFX12V, LFX12V, ATX12V, SFX12V, and TFX12V content into one desktop power supply design guide
  • CFX12V content derived from revision 1.2
  • Updated 12V1 current for 300 W configuration
  • Updated efficiency loading for 300 W configuration
    • LFX12V content derived from revision 1.1
    • ATX12V content derived from revision 2.2
    • SFX12V content derived from revision 3.1
    • TFX12V content derived from revision 2.1
  • Updated 12V1 current for 300 W configuration
  • Updated efficiency loading for 300 W configuration
    • Updated Capacitive Load section to use standard capacitor values
    • Updated 5 VSB efficiency recommendations for Digital Office platforms
    • Removed power-down warning from power supply timing diagram
    • Marked sections with labels to indicate REQUIRED, RECOMMENDED, or OPTIONAL items

January 2006

1.0

  • Added 12V2 Current for Processor Configurations table
  • Added revision numbers to form factor specific chapters

June 2006

1.1

  • Removed outdated ENERGY STAR* requirements and added some new ENERGY STAR information.
  • Updated Typical Power Distribution tables for all power supply form factors and updated minimum loads.
  • Updated cross regulation figures.
  • Added Flex ATX power supply form factor.
  • Updated capacitive loading table.
  • Clarified over voltage and over current verbiage.
  • Added Power-up Cross Loading Condition section.
  • Other changes shown in red with change bars.

March 2007

1.2

  • Section 4.3.1 and Added max of 400 mV Ripple/Noise to PS_​ON and PWR_​OK signals
  • Section 14.2 Figure 49 replaced to implement change in dimension C
  • Section 4.3 Added Power-down timing to Figure 4-3 and Table 4-9: Power Supply Timing Table 4-9 (T6 > 1 ms)
  • Section 8.3 Clarified Class D requirements. Added additional references for EMC requirements by country
  • Section 4.5.9 Added Climate Savers Computing text
  • Updated all Cross-regulation graphs
  • Section 2 updated configuration charts
  • Removed dates from reference documentation. Refer to the latest version available
  • Updated Figure 58

February 2008

1.3

July 2012

1.31

  • Updated Table 4-5 Recommended System DC and AC power consumption
  • Changed Section 4.2.10 12 V2DC Minimum Loading to REQUIRED
  • Updated Section 4.3.6 Rise Time
  • Updated
    • CFX12V Specific Guidelines to version 1.5
    • LFX12V Specific Guidelines to version 1.3
    • ATX12V Specific Guidelines to version 2.4
    • SFX12V Specific Guidelines to version 3.3
    • TFX12V Specific Guidelines to version 2.4
    • Flex ATX Specific Guidelines to version 1.1

April 2013

1.4

  • Updated Section 1.2, Table 1-1 with new terminology
  • Updated Section 2.1 peak and sustain current requirements
  • Updated Section 3.1 Table 4-1 – removed current values in table
  • Updated Section 4.2.2, Table 4-3 – 12V1 and 12V2 new step size, added 12V3/4 step size
  • Updated Section 4.2.4 - low power 5VSB efficiency
  • Updated Section 4.2.6, Table 4-7 – Decoupling cap values were changed
  • Added Figure 4-2 in Section 4.2.8
  • Updated Section 4.2.10, Table 4-8 – 12V2 recommendation is now required
  • Updated Section 4.3, Table 4-9 now shows T0, Timing requirements T1 and T3 added for ALPM and note about timing requirements in the year 2020
  • Updated Section 4.3.4 to provide recommendation to increase current on 5VSB for computers with ALPM
  • Added Figure 4-6 in section 4.3.6 for more clarity
  • Updated Section 4.4.2 5VSB fall time as recommendation and loading conditions used in the test plan
  • Re-wrote Section 4.5.8 for overall efficiency targets – Added Section about Low Load Condition
  • Re-wrote Section 4.5.9 to include Efficiency recommendations for current Energy Regulations
  • Updated Section 5.1 to include labeling instructions for which DG timings are supported by the PSU
  • Updated Section 5.2.2.3 Floppy Drive Connector to be reference only
  • Added Section 5.2.2.4 for PCIe* AIC connectors
  • Updated Section 5.2.2.4.2, added Table 5-5 +12V power 8 pin connector pin out
  • Updated Section 6.1 – Acoustic note about acoustic targets can be customer specific
  • Sections 11, 12, 13, 14, 15 and 16 Added form factor revision summary to beginning of each form factor specific section
  • Added new Intel Test Plan Section

June 2017

1.41

  • Update Section 2.1Table 2-1 for 12V2 Processor sustain and peak power updates
  • Added Section 2.2 for HEDT processors support
  • Updated Section 4.5.8 and added Table 4-14
  • Update Section 4.3 – add note for T3
  • Update Section 4.5.9 – for ENERGY STAR* Computers Version 7.0
  • Updated Chapters 11, 12, 13, 14, 15, and 16
  • CFX12V Specific Guidelines to version 1.61

    LFX12V Specific Guidelines to version 1.41

    ATX12V Specific Guidelines to version 2.51

    SFX12V Specific Guidelines to version 3.41

    TFX12V Specific Guidelines to version 2.51

    Flex ATX Specific Guidelines to version 1.21

  • Updated Test Plan Sections 16.2.1 and Table 16-2 - 12V2 load table - to match Table 2-1
  • Updated Test Plan Sections 16.2.2 and Table 16-3 for new 95W load of 21A Continuous
  • Updated Test Plan Sections 16.3.3 and Table 16-10 – added 12W load level
  • Updated Test Plan Section 16.6 to include mention of PSU for new CPU TDP levels mentioned in Section 2.1

October 2017

1.42

  • Update Table 2-1: 12V2 Current for Processor Configurations.
  • Update Figure 4-3: Power Supply Timing.
  • Add Figure 4-5: +5VSB Power on timing versus VAC.
  • Add note : +3.3V is removed from SATA V3.2 spec.
  • Updated Chapters 11, 12, 13, 14, 15, and 16
  • CFX12V Specific Guidelines to version 1.62

    LFX12V Specific Guidelines to version 1.42

    ATX12V Specific Guidelines to version 2.52

    SFX12V Specific Guidelines to version 3.42

    TFX12V Specific Guidelines to version 2.52

    Flex ATX Specific Guidelines to version 1.22

  • Remove Test Plan Section. Refer to Document #338448 for test plan.
  • Add Section 10.2 Reliability – PS_​ON# toggle for S0ix mode.

May 2018

1.43

  • Update Table 2-1: 12V2 Current for Processor Configurations.
  • Change -12VDC capacitive load from 3300uF to 330uF.
  • Updated Chapters 11, 12, 13, 14, 15 and 16
  • CFX12V Specific Guidelines to version 1.63

    LFX12V Specific Guidelines to version 1.43

    ATX12V Specific Guidelines to version 2.53

    SFX12V Specific Guidelines to version 3.43

    TFX12V Specific Guidelines to version 2.53

    Flex ATX Specific Guidelines to version 1.23

  • Update Table 4-5 5VSB efficiency

March 2019

1.43.01

  • Updated Table 2-1 to correct the 12V2 peak current requirement of 165W.
  • Changed the Section 1.1 topic to “Alternative Low Power Mode” for Power Supplies.
  • Added PSU Addendum for all future processor support in Section 2.1.
  • Updated Section 4.5.9 to support Energy Star v8.

May 2020

2.0

  • Updated text for clarity in Section Section 1: Introduction
  • Section Section 1.1 added second reference for ALPM in Section 4.3.3
  • Section Section 1.2 – Added new Reference Documentations to list
  • Updated Table 2-1 and reference text for Processors
  • Section Section 2.2- Updated to provide clarity
  • Added ALL of Section Section 3 – PCIe* Add-in Card Consideration
  • Updated Section Section 4.2.1 and Table 4-2: DC Output Voltage Regulation4.2.1– +12V Voltage range changed
  • Updated Table 4-3 - DC Voltage step size modified for 12V2 & 12V3/4.
  • Added Table 4-4: DC Output Transient Slew Rate and text describing Slew Rate
  • Updated Table 4-9: Power Supply Timing – Previous Required value is now Legacy Timings and Previous Recommended is now Required.
  • Updated Section Section 4.3.3 – to include mention response to PS_​ON# changes beyond 100 ms
  • Simplified Table 4-14: Low Load Efficiency Requirements
  • Section Section 5.1 – Added mention for label of all PSUs should state revision of the specification that it meets and 12VHPWR label for power level supported
  • Section Section 5.2.2.4 – PCIe* Graphics Card Connector section increased detail for all 3 connector options including new 12VHPWR connector.
  • Chapter Chapter 11, 12, 13, 14, 15, and 16 – Changed table at beginning of each section to represent new mechanical size Specification Revision.

February 2022

2.01

  • Table 2-1 - Changed top row from 165W to 150W and associated power values to correspond to latest updates in the PSU Design Guide Addendum document.
    • Table 3-3 - Duty Cycle for Peak Events change to match the PSU Test Plan document.
    • Table 3-4 - Whole table updated related to Duty Cycle for Peak Events change to match the PSU Test Plan document.
    • Table 4-3 - Added Note #4 that references Dynamic Mode testing for each 12VHPWR Connector in the system.
    • Section 4.2.2 - Fixed reference for Table 4-4 on page 32.
    • Table 4-4 – Changed word “Rated” to “Recommended” in the top row of the table.
    • Table 4-11 - Note 2 – Updated reference from an external document to Section 10.2, which already covered the items listed in this document.
    • Table 4-15 – Added column for 10% Load as defined in ENERGY STAR* for Computers v8
    • Section 5.1 – Changed how 12VHPWR connector power limit labeling can be done. Change from “Required” to “Recommended” for having the 12VHPWR connector power limit on the 12VHPWR connector. Reason is if a PSU uses a modular designs with detachable cables, then the 12VHPWR power limit can be listed on PSU Label. 12VHPWR connector limit must be listed in one of these locations.
    • Section 5.2.2.4.3 – Added mention of two options for 12VHPWR Connector, header changed to “Recommended” for PSUs> 450 watts
    • Figure 5-3 and Figure 5-4 – updated figures with new pictures of both 12VHPWR connector options
    • Section 5.2.2.4.3 and Figure 5-5 – Added paragraph & figure about 12VHPWR Cable Plug Connection Recommendations

February 2023