ATX12VO (12V Only) Desktop Power Supply

Design Guide

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ID 613768
Date 01/03/2022
Public

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Document Table of Contents
Document Table of Contents
Legal Introduction Processor Configurations PCI Express* Add-in Card Considerations Electrical Mechanical Acoustics Environmental Electromagnetic Compatibility Safety Reliability CFX12V Specific Guidelines 2.0 LFX12V Specific Guidelines 2.0 ATX12V Specific Guidelines 3.0 SFX12V Specific Guidelines 4.0 TFX12V Specific Guidelines 3.0 Flex ATX Specific Guidelines 2.0
Legal
Introduction
Introduction Power Supplies and Alternative Low Power Mode System Power Telemetry Feature References Terminology
Power Supplies and Alternative Low Power Mode
System Power Telemetry Feature
References
Terminology
Processor Configurations
Processor Configurations (Recommended) High End Desktop Market Processor Considerations
Processor Configurations (Recommended)
High End Desktop Market Processor Considerations
High End Desktop Market Processor Considerations Modular Power Supply Connectors Overclocking Recommendations
Modular Power Supply Connectors
Overclocking Recommendations
PCI Express* Add-in Card Considerations
PCI Express* Add-in Card Considerations PCIe* Add-in Card Power Excursions PCIe* AIC Auxiliary Power Connectors PCIe* Add-in-Card Auxiliary Power Connectors Sideband Signals
PCIe* Add-in Card Power Excursions
PCIe* Add-in Card Power Excursions PCIe* Add-in-Card and PSU Power Budgets PSU Power Excursion
PCIe* Add-in-Card and PSU Power Budgets
PSU Power Excursion
PCIe* AIC Auxiliary Power Connectors
PCIe* Add-in-Card Auxiliary Power Connectors Sideband Signals
PCIe* Add-in-Card Auxiliary Power Connectors Sideband Signals Sense1 / Sense0 (Required) CARD_PWR_STABLE (Optional) CARD_CBL_PRES# (Optional) Sideband Signals DC Specifications (Required)
Sense1 / Sense0 (Required)
CARD_PWR_STABLE (Optional)
CARD_CBL_PRES# (Optional)
Sideband Signals DC Specifications (Required)
Electrical
Electrical AC Input – REQUIRED DC Output (Required) Timing, Housekeeping, and Control (Required) Reset After Shutdown Output Protection
AC Input – REQUIRED
AC Input – REQUIRED Input Over Current Protection (Required) Inrush Current (Required) Input Under Voltage (Required)
Input Over Current Protection (Required)
Inrush Current (Required)
Input Under Voltage (Required)
DC Output (Required)
DC Output (Required) DC Voltage Regulation (Required) DC Output Current (Required) Remote Sensing (Optional) Other Low Power System Requirements (Required) Output Ripple Noise (Required) Capacitive Load (Recommended) Closed Loop Stability (Required) Multiple 12V Rail Power Sequencing (Required) Voltage Hold-Up Time (Required)
DC Voltage Regulation (Required)
DC Output Current (Required)
Remote Sensing (Optional)
Other Low Power System Requirements (Required)
Output Ripple Noise (Required)
Capacitive Load (Recommended)
Closed Loop Stability (Required)
Multiple 12V Rail Power Sequencing (Required)
Voltage Hold-Up Time (Required)
Timing, Housekeeping, and Control (Required)
Timing, Housekeeping, and Control (Required) PWR_OK (Required) PS_ON# (Required) +12VSB (Required) Power-On Time (Required) Rise Time (Required) Overshoot at Turn-On / Turn-Off (Required) I_PSU% Singal (Required)
PWR_OK (Required)
PS_ON# (Required)
+12VSB (Required)
Power-On Time (Required)
Rise Time (Required)
Overshoot at Turn-On / Turn-Off (Required)
I_PSU% Singal (Required)
Reset After Shutdown
Reset After Shutdown +12VSB at Power-Down (Required) +12VSB Fall Time (Recommended)
+12VSB at Power-Down (Required)
+12VSB Fall Time (Recommended)
Output Protection
Over Voltage Protection (OVP) (Required) Short Circuit Protection (SCP) (Required) No-Load Situation (Required) Over Current Protection (OCP) (Required) Over Temperature Protection (OTP) (Required) Output Bypass (Required) Separate Current Limit for 12V2 (Optional) Overall Power Supply Efficiency Levels Power Supply Efficiency for Energy Regulations - ENERGY STAR* and CEC PC Computers with High Expandability Score (Recommended)
Over Voltage Protection (OVP) (Required)
Short Circuit Protection (SCP) (Required)
No-Load Situation (Required)
Over Current Protection (OCP) (Required)
Over Temperature Protection (OTP) (Required)
Output Bypass (Required)
Separate Current Limit for 12V2 (Optional)
Overall Power Supply Efficiency Levels
Power Supply Efficiency for Energy Regulations - ENERGY STAR* and CEC PC Computers with High Expandability Score (Recommended)
Mechanical
Mechanical Labeling and Marking (Recommended) Connectors (Required) Connector from Motherboard to Storage Devices – Reference Airflow and Fans (Recommended)
Labeling and Marking (Recommended)
Connectors (Required)
AC Connector DC Connectors
AC Connector
DC Connectors
Connector from Motherboard to Storage Devices – Reference
Connector from Motherboard to Storage Devices – Reference Motherboard Connector Serial ATA Connectors (Reference)
Motherboard Connector
Serial ATA Connectors (Reference)
Airflow and Fans (Recommended)
Airflow and Fans (Recommended) Fan Location and Direction Fan Size and Speed Venting
Fan Location and Direction
Fan Size and Speed
Venting
Acoustics
Environmental
Environmental Temperature (Recommended) Thermal Shock (Shipping) Humidity (Recommended) Altitude (Recommended) Mechanical Shock (Recommended) Random Vibration (Recommended)
Temperature (Recommended)
Thermal Shock (Shipping)
Humidity (Recommended)
Altitude (Recommended)
Mechanical Shock (Recommended)
Random Vibration (Recommended)
Electromagnetic Compatibility
Electromagnetic Compatibility Emissions (Required) Immunity (Required) Input Line Current Harmonic Content (Optional) Magnetic Leakage Field (Required) Voltage Fluctuations and Flicker (Required)
Emissions (Required)
Immunity (Required)
Input Line Current Harmonic Content (Optional)
Magnetic Leakage Field (Required)
Voltage Fluctuations and Flicker (Required)
Safety
Safety North America (Required) International (Required) Proscribed Materials (Required) Catastrophic Failure Protection (Recommended)
North America (Required)
International (Required)
Proscribed Materials (Required)
Catastrophic Failure Protection (Recommended)
Reliability
Reliability (Recommended) Reliability – PS_ON# Toggle for S0ix Mode (Required)
Reliability (Recommended)
Reliability – PS_ON# Toggle for S0ix Mode (Required)
CFX12V Specific Guidelines 2.0
CFX12V Specific Guidelines 2.0 Physical Dimensions (Required)
Physical Dimensions (Required)
LFX12V Specific Guidelines 2.0
LFX12V Specific Guidelines 2.0 Physical Dimensions (Required)
Physical Dimensions (Required)
ATX12V Specific Guidelines 3.0
SFX12V Specific Guidelines 4.0
SFX12V Specific Guidelines 4.0 Lower Profile Package – Physical Dimensions (Required) Fan Requirements (Required) Top Fan Mount Package – Physical Dimensions (Required) Fan Requirements (Required) Reduced Depth Top Mount Fan – Physical Dimensions (Required) Fan Requirements (Required) Standard SFX Profile Package – Physical Dimensions (Required) Fan Requirements (Required) PS3 Form Factor – Physical Dimensions (Required) Fan Requirements (Required)
Lower Profile Package – Physical Dimensions (Required)
Fan Requirements (Required)
Top Fan Mount Package – Physical Dimensions (Required)
Fan Requirements (Required)
Reduced Depth Top Mount Fan – Physical Dimensions (Required)
Fan Requirements (Required)
Standard SFX Profile Package – Physical Dimensions (Required)
Fan Requirements (Required)
PS3 Form Factor – Physical Dimensions (Required)
Fan Requirements (Required)
TFX12V Specific Guidelines 3.0
TFX12V Specific Guidelines 3.0 Physical Dimensions (Required) Mounting Options (Recommended) Chassis Requirements (Recommended)
Physical Dimensions (Required)
Mounting Options (Recommended)
Chassis Requirements (Recommended)
Flex ATX Specific Guidelines 2.0
Flex ATX Specific Guidelines 2.0 Physical Dimensions (Required)
Physical Dimensions (Required)
Legal
Introduction
Processor Configurations
PCI Express* Add-in Card Considerations
Electrical
Mechanical
Acoustics
Environmental
Electromagnetic Compatibility
Safety
Reliability
CFX12V Specific Guidelines 2.0
LFX12V Specific Guidelines 2.0
ATX12V Specific Guidelines 3.0
SFX12V Specific Guidelines 4.0
TFX12V Specific Guidelines 3.0
Flex ATX Specific Guidelines 2.0

Fan Size and Speed

A thermally sensitive fan speed control circuit is recommended to balance system-level thermal and acoustic performance. The circuit typically senses the temperature of the secondary heatsink and/or incoming ambient air and adjusts the fan speed as necessary to keep power supply and system component temperatures within specification. Both the power supply and system designers should be aware of the dependencies of the power supply and system temperatures on the control circuit response curve and fan size and should specify them carefully.

Fan should not turn on at the same time as PS_​ON# is Asserted. This is because of power optimization at low levels and Alternative Low Power Modes. Two options to consider:

  1. Wait for at least 2 seconds before the fan turns on.
  2. Fan must be turned ON only when the PSU needs the thermal cooling.

The power supply fan should be turned off when PS_​ON# is de-asserted (high). In this state, any remaining active power supply circuitry must rely only on passive convection for cooling.

Venting