ATX12VO (12V Only) Desktop Power Supply
Design Guide
ID
613768
Date
01/03/2022
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 (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)
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)
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)
PCI Express* Add-in Card Considerations
The PCI Express* (PCIe*) Card Electromechanical Specification (CEM Spec) provides thermal, power, mechanical, and signal integrity design guidance for the PCI Express* Add-in Card (AIC) form factor. This includes the card’s electrical and mechanical interface with a host system board, chassis, and power supply.
The 5.0 Revision of the PCIe* spec introduces four significant updates that directly affect this power supply specification:
- A Power Excursion allowance was introduced to support brief, high current demands on power, beyond the rated TDP.
- The maximum power consumption for a single Add-in Card was doubled to 600 W. This is the per-card limit from all sources combined.
- A new 48V (nominal) power rail was added.
- Two new Auxiliary Power Connectors were introduced to provide the full 600 W on a single cable connector. The new 12VHPWR connector supports 600W on the 12V rail while the 48VHPWR provides 600W on the 48V rail. Four new sideband signal conductors permit simple signaling between the Add-in Card and power supply.