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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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
DC Output – REQUIRED
DC Voltage Regulation – REQUIRED
DC Output Current – REQUIRED
Remote Sensing - RECOMMENDED
Other Low Power System Requirements
Output Ripple Noise - REQUIRED
Capacitive Load – RECOMMENDED
Closed Loop Stability - REQUIRED
+5V DC / +3.3V DC Power Sequencing - REQUIRED
Voltage Hold-Up Time - REQUIRED
12V2 DC Minimum Loading - REQUIRED
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 (California Energy Commission) PC Computers with High Expandability Score - RECOMMENDED
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
Fan Requirements - REQUIRED
Standard SFX Profile Package – Physical Dimensions - REQUIRED
Fan Requirements - REQUIRED
PS3 Form Factor-Physical Dimensions - REQUIRED
Fan Requirements - REQUIRED
Fan Location and Direction
In general, exhausting air from the system chassis enclosure via a power supply fan at the rear panel is the preferred, most common, and most widely applicable system-level airflow solution. However, some system/chassis designers may choose to use other configurations to meet specific system cooling requirements.