ATX Version 3.0 Multi Rail Desktop Platform Power Supply

Design Guide

ID 336521
Date 01/02/2022
Version 2.0
Public
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Removed outdated ENERGY STAR* requirements and added some new ENERGY STAR information.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 TimingTable 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

Updated Section 4.2.3 Remote sensing to recommended level

Added Section 4.2.10 12 V2DC Minimum Loading Recommendation

Added Section 4.4.2 +5 VSB Fall time Recommendation

Updated Section 4.2.9 Voltage Hold-up Time

Updated Section 4.5.9 Overall Power Supply Efficiency and ENERGY STAR

Changed Floppy Drive Connector to OPTIONAL level

Changed Section 5.2.2.6 Serial ATA Connectors to Required level

Update Table 2-1: 12V2 Current for Processor Configurations

Updated Table 4-2: DC Output Voltage Regulation -12V to recommended level

Updated Table 4-5: Recommended System DC and AC power consumption

Updated Table 4-9 Power Supply Timing recommended value

Updated Table 4-15: Efficiency versus Load

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 Chapter Chapter 1: Introduction

Added Section Section 1.1

Added second reference for ALPM in Section 4.3.3

Added new Reference Documentations to list in Section Section 1.2

Updated Table 2-1 and reference text for Processors

Updated Section Section 2.2 to provide clarity

Added ALL of Chapter Chapter 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

Added mention for label of all PSUs should state revision of the specification that it meets and 12VHPWR label for power level supported in Section Section 5.1

Added PCIe* Graphics Card Connector section increased detail for all 3 connector options including new 12VHPWR connector in Section Section 5.2.2.4

Changed table at beginning of each section to represent new mechanical size Specification Revision in Chapter Chapter 11, 12, 13, 14, 15, and 16

February 2022