Intel 0.9 Contents, Scope, Applicable Documents, Mechanical Requirements, Electrical Specification

Intel ATX Power Supply Design Guide

Version 0.9

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

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