Intel ATX 0.9 User Manual
Page 3
Intel ATX Power Supply Design Guide
Version 0.9
Page
3
Contents
1. Scope .................................................................................................................. 6
2. Applicable Documents ...................................................................................... 7
3. Electrical Specification ..................................................................................... 8
3.1
AC Input Requirements .........................................................................................................8
3.1.1
Input Overcurrent Protection.....................................................................................8
3.1.2
Inrush Current Limiting .............................................................................................8
3.1.3
Input Undervoltage ...................................................................................................8
3.1.4
Immunity ...................................................................................................................9
3.1.5
Catastrophic Failure Protection ................................................................................11
3.2
DC Output Requirements ......................................................................................................11
3.2.1
DC Voltage Regulation .............................................................................................11
3.2.2
Remote Sensing .......................................................................................................11
3.3
Typical Power Distribution .....................................................................................................12
3.3.1
Power Limit ...............................................................................................................13
3.3.2
Efficiency ..................................................................................................................13
3.3.3
Output Ripple/Noise..................................................................................................14
3.3.4
Output Transient Response......................................................................................14
3.3.5
Capacitive Load ........................................................................................................14
3.3.6
Closed Loop Stability ................................................................................................14
3.3.7
+5VDC/+3.3VDC Power Sequencing .......................................................................15
3.3.8
Voltage Hold-up Time ...............................................................................................15
3.4
Timing / Housekeeping / Control ...........................................................................................16
3.4.1
PWR_OK ..................................................................................................................16
3.4.2
PS_ON#....................................................................................................................17
3.4.3
+5VSB.......................................................................................................................17
3.4.4
Power-on Time .........................................................................................................17
3.4.5
Risetime....................................................................................................................18
3.4.6
Overshoot at Turn-on/Turn-off..................................................................................18
3.4.7
Reset after Shutdown ...............................................................................................18
3.4.8
+5VSB at AC Power Down .......................................................................................18
3.5
Output Protection...................................................................................................................19
3.5.1
Overvoltage Protection .............................................................................................19
3.5.2
Short Circuit Protection.............................................................................................19
3.5.3
No Load Operation ...................................................................................................19
3.5.4
Overcurrent Protection..............................................................................................19
3.5.5
Output Bypass ..........................................................................................................19
4. Mechanical Requirements ................................................................................ 20
4.1
Labeling / Marking .................................................................................................................20
4.2
Physical Dimensions..............................................................................................................20
4.3
Airflow / Fan...........................................................................................................................23