Intel ATX - Default Chapter; Table of Contents

Design Guide 3
Contents
1 Introduction ..................................................................................................... 8
1.1 Alternative Low Power Mode for Power Supplies .......................................... 8
1.2 References ............................................................................................ 8
1.3 Terminology .......................................................................................... 9
2 Processor Configurations .................................................................................. 11
2.1 Processor Configurations – Recommended ............................................... 11
2.2 High End Desktop Market Processor Considerations ................................... 12
2.2.1 Modular Power Supply Connectors ............................................. 12
2.2.2 Overclocking Recommendations ................................................ 13
3 Electrical ....................................................................................................... 14
3.1 AC Input - Required .............................................................................. 14
3.1.1 Input Over Current Protection – Required ................................... 14
3.1.2 Inrush Current – Required ........................................................ 14
3.1.3 Input Under Voltage – Required ................................................ 14
3.2 DC Output - Required ........................................................................... 15
3.2.1 DC Voltage Regulation – Required.............................................. 15
3.2.2 DC Output Current – Required ................................................... 15
3.2.3 Remote Sensing - Recommended .............................................. 16
3.2.4 Other Low Power System Requirements - Recommended .............. 16
3.2.5 Output Ripple Noise - Required ................................................. 17
3.2.6 Capacitive Load – Recommended ............................................... 18
3.2.7 Closed Loop Stability - Required ................................................ 18
3.2.8 +5V DC / +3.3V DC Power Sequencing - Required ....................... 18
3.2.9 Voltage Hold-Up Time - Required ............................................... 19
3.2.10 12V2 DC Minimum Loading - Required ........................................ 19
3.3 Timing, Housekeeping, and Control – Required ......................................... 20
3.3.1 PWR_OK – Required ................................................................ 21
3.3.2 Power-Up Cross Loading Condition – Required ............................. 21
3.3.3 PS_ON# – Required ................................................................. 22
3.3.4 +5VSB – Required ................................................................... 23
3.3.5 Power-On Time – Required ....................................................... 24
3.3.6 Rise Time – Required ............................................................... 24
3.3.7 Overshoot at Turn-On/Turn-Off – Required ................................. 25
3.4 Reset After Shutdown ........................................................................... 25
3.4.1 +5VSB at Power-Down – Required ............................................. 25
3.4.2 +5VSB Fall Time - Recommendation .......................................... 26
3.5 Output Protection ................................................................................. 26
3.5.1 Over Voltage Protection (OVP) – Required ................................... 26
3.5.2 Short Circuit Protection (SCP) – Required ................................... 27
3.5.3 No-Load Situation – Required .................................................... 27
3.5.4 Over Current Protection (OCP) – Required................................... 27
3.5.5 Over Temperature Protection (OTP) – Required ........................... 27
3.5.6 Output Bypass – Required ........................................................ 27
3.5.7 Separate Current Limit for 12V2 - Recommended ......................... 27
3.5.8 Overall Power Supply Efficiency Levels ....................................... 28
3.5.9 Power Supply Efficiency for Energy Regulations - Energy Star* and
CEC PC Computers with High Expandability Score - Recommended . 28