ATX12VO (12V Only) Desktop Power Supply
Design Guide
ID | Date | Version | Classification |
---|---|---|---|
613768 | 05/01/2024 | 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 2.1
LFX12V Specific Guidelines 2.1
ATX12V Specific Guidelines 3.1
SFX12V Specific Guidelines 4.1
TFX12V Specific Guidelines 3.1
Flex ATX Specific Guidelines 2.1
DC Output – REQUIRED
DC Voltage Regulation – REQUIRED
DC Output Current – REQUIRED
Remote Sensing – RECOMMENDED
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/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 (California Energy Commission) PC Computers with High Expandability Score – RECOMMENDED
SFX12V Specific Guidelines 4.1
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)
Separate Current Limit for 12V2 - OPTIONAL
The 12 V rail on the 2x2 power connector should be a separate current limited output to meet the requirements of UL and EN 62368-1. This only applies if the PSU is complying a 240VA Energy Hazard Safety Requirement; most power supplies are not currently designed to meet this requirement.