1. Manuals
  2. Brands
  3. Intel Manuals
  4. Power Supply
  5. ATX12V
  6. Design manual

Intel ATX12V Design Manual

Intel power supply user guide
Hide thumbs
Table of Contents

Advertisement

Quick Links

ATX12V
Power Supply Design Guide
Version 2.0

Advertisement

Table of Contents
loading

Related Manuals for Intel ATX12V

Summary of Contents for Intel ATX12V

  • Page 1 ATX12V Power Supply Design Guide Version 2.0...
  • Page 2 MEDICAL OR LIFE SAVING APPLICATIONS, OR IN NUCLEAR FACILITY APPLICATIONS. NO LICENSE, EXPRESS OR IMPLIED, BY ESTOPPEL OR OTHERWISE, TO ANY INTELLECTUAL PROPERTY RIGHTS IS GRANTED HEREIN. Intel and Pentium are registered trademarks of Intel Corporation or its subsidiaries in the United States and other countries. ...

  • Page 3: Table Of Contents

    Contents 1. Introduction ... 6 1.1. Scope ...6 1.2. Key Changes for ATX12V Version 2.0 as Compared with ATX Power Supply...6 1.2.1. Increased +12 VDC output capability ...6 1.2.2. Minimum Efficiency...6 1.2.3. Main Power Connector: ...7 1.2.4. Separate current limit for 12V2 on the 2x2 connector: ...7 1.3 Terminology...7...
  • Page 4 ATX12V Power Supply Design Guide Version 2.0 3.4.3. No-load Operation ...26 3.4.4. Over-current Protection ...26 3.4.5. Over-temperature Protection ...27 3.4.6. Output Bypass ...27 4. Mechanical... 28 4.1. Labeling / Marking ...28 4.2. Physical Dimensions ...28 4.3. Airflow / Fan...31 4.4. AC Connector ...32 4.5.
  • Page 5 Table 1. AC Input Line Requirements...9 Table 2. DC Output Voltage Regulation...11 Table 3. Typical Power Distribution for a 250 W ATX12V Configuration...13 Table 4. Typical Power Distribution for a 300 W ATX12V Configuration...14 Table 5. Typical Power Distribution for a 350 W ATX12V Configuration...15 Table 6.

  • Page 6: Introduction

    ATX Power Supply This section briefly summarizes the major changes made to this document that now defines ATX12V power supply. With the move to 12V voltage regulators for the processor, ATX guidelines for 5V as main power are no longer provided.

  • Page 7: Main Power Connector

    Declared sound power, LwAd. The declared sound power level shall be measured according to ISO* 7779 for the power supply and reported according to ISO 9296. Cubic Feet per Minute (airflow).

  • Page 8: Applicable Documents

    ATX12V Power Supply Design Guide Version 2.0 2. Applicable Documents The following documents support this design guide as additional reference material. Document Title Description FCC Rules Part 15, Class B Title 47, Code of Federal Regulations, Part 15 ICES-003: 1997, Class B Interference-Causing Equipment Standard –...

  • Page 9: Electrical

    . For Denmark and Switzerland international safety requirements, if the internal over-current protective devices exceed 8A for Denmark and 10A for Switzerland, then the power supply must pass international safety testing to EN 60950 using a maximum 16A over-current protected branch circuit, and this 16A (time delay fuse) branch circuit protector must not open during power supply abnormal operation (output short circuit and component fault) testing.

  • Page 10: Input Under-Voltage

    Section 3.1, Table 1, shall not cause damage to the power supply. 3.1.4. Regulatory The power supply is required to be tested and comply with the most current version of the following regulatory specification requirements and/or standards PRODUCT SAFETY UL* 60950, 3 Edition –CAN/CSA-C22.2-60950-00,...

  • Page 11: Catastrophic Failure Protection

    3.1.5. Catastrophic Failure Protection Should a component failure occur, the power supply should not exhibit any of the following: • Flame • Excessive smoke • Charred PCB • Fused PCB conductor • Startling noise • Emission of molten material 3.2. DC Output 3.2.1.

  • Page 12: Remote Sensing

    The default sense should be connected to pin 11 of the main power connector. The power supply should draw no more than 10 mA through the remote sense line to keep DC offset voltages to a minimum.

  • Page 13: Figure 1. Cross Loading Graph For 250W Configuration

    3.2.3.1. ATX12V Configurations Table 3. Typical Power Distribution for a 250 W ATX12V Configuration Min. Current Output (amps) +12 V1DC +12 V2DC +5 VDC +3.3 VDC -12 VDC +5 VSB Note: Total combined output of 3.3 V and 5 V is Peak currents may last up to 17 seconds with not more than one occurrence per minute 12V1DC and 12V2DC should have separate current limit circuits to meet 240VA safety requirements.

  • Page 14: Figure 2. Cross Loading Graph For 300W Configuration

    ATX12V Power Supply Design Guide Version 2.0 Table 4. Typical Power Distribution for a 300 W ATX12V Configuration Min. Current Output (amps) +12 V1DC +12 V2DC +5 VDC +3.3 VDC -12 VDC +5 VSB Note: Total combined output of 3.3 V and 5 V is Peak currents may last up to 17 seconds with not more than one occurrence per minute 12V1DC and 12V2DC should have separate current limit circuits to meet 240VA safety requirements.

  • Page 15: Figure 3. Cross Loading Graph For 350W Configuration

    Table 5. Typical Power Distribution for a 350 W ATX12V Configuration Min. Current Current Output (amps) (amps) +12 V1DC +12 V2DC +5 VDC +3.3 VDC -12 VDC +5 VSB Note: Total combined output of 3.3 V and 5 V is Peak currents may last up to 17 seconds with not more than one occurrence per minute 12V1DC and 12V2DC should have separate current limit circuits to meet 240VA safety requirements.

  • Page 16: Figure 4. Cross Loading Graph For 400W Configuration

    ATX12V Power Supply Design Guide Version 2.0 Table 6. Typical Power Distribution for a 400 W ATX12V Configuration Min. Current Output (amps) +12 V1DC +12 V2DC +5 VDC +3.3 VDC -12 VDC +5 VSB Note: Total combined output of 3.3 V and 5 V is Peak currents may last up to 17 seconds with not more than one occurrence per minute 12V1DC and 12V2DC should have separate current limit circuits to meet 240VA safety requirements.

  • Page 17: Power Limit / Hazardous Energy Levels

    3.2.5. Efficiency 3.2.5.1. General The power supply required minimum is 70% efficient under “Full” load, 70% under “typical” load, and 60% in a “light” load or idle condition. The efficiency of the power supply should be tested at nominal input voltage of 115VAC input and/or 230VAC input, under the load conditions defined in Table 7 and Table 8, and under the temperature and operating conditions defined in Section 5.

  • Page 18: Table 8. Loading Table For Efficiency Measurements

    ATX12V Power Supply Design Guide Version 2.0 Table 8. Loading Table for Efficiency Measurements Loading +12V1 Full Typical Light Loading +12V1 Full Typical Light Loading +12V1 Full Typical Light Loading +12V1 Full Typical Light 250W (loading shown in Amps) +12V2 +3.3V...

  • Page 19: Output Ripple/Noise

    3.2.5.2. Energy Star* The “Energy Star” efficiency requirements of the power supply depend on the intended system configuration. In the low-power / sleep state (S1 or S3) the system should consume power in accordance with the values listed inTable 9.

  • Page 20: Figure 5. Differential Noise Test Setup

    ATX12V Power Supply Design Guide Version 2.0 Table 10. DC Output Noise/Ripple Max. Ripple & Noise Output +12 V1DC +12 V2DC +5 VDC +3.3 VDC -12 VDC +5 VSB V out Power Supply AC Hot AC Neutral V return AC Ground General Notes: 1.

  • Page 21: Output Transient Response

    • Capacitive loading per Table 12. 3.2.8. Capacitive Load The power supply should be able to power up and operate normally with the following capacitances simultaneously present on the DC outputs. This capacitive loading should be used to check stability and should not be included for noise testing.

  • Page 22: Closed-Loop Stability

    ≤ 20 ms. 3.2.11. Voltage Hold-up Time The power supply should maintain output regulation per Section 3.2.1 despite a loss of input power at the low-end nominal range—115 VAC / 57 Hz or 230 VAC / 47 Hz—at maximum continuous output load as applicable for a minimum of 17 ms.

  • Page 23: Pwr_Ok

    3.3.1. PWR_OK PWR_OK is a “power good” signal. It should be asserted high by the power supply to indicate that the +12 VDC, +5VDC, and +3.3VDC outputs are above the under-voltage thresholds listed in Section 3.2.1 and that sufficient mains energy is stored by the converter to guarantee continuous power operation within specification for at least the duration specified in Section 3.2.11, “Voltage Hold-up Time.”...

  • Page 24: Vsb

    The +5 VSB output should be capable of delivering a minimum of 2.0 A at +5 V ± 5% to external circuits. The power supply must be able to provide the required power during a "wake up" event. If an external USB device generates the event, there may be peak currents as high as 2.5A lasting no more than 500mS.

  • Page 25: Power-On Time

    3.3.7. Reset after Shutdown If the power supply latches into a shutdown state because of a fault condition on its outputs, the power supply shall return to normal operation only after the fault has been removed and the PS_ON# (or AC input) has been cycled OFF/ON with a minimum OFF time of 1 second.

  • Page 26: Output Protection

    An output short circuit is defined as any output impedance of less than 0.1 ohms. The power supply shall shut down and latch off for shorting the +3.3 VDC, +5 VDC, or +12 VDC rails to return or any other rail. The +12 V1DC and +12V2DC should have separate short circuit and overload protection.

  • Page 27: Over-Temperature Protection

    The power supply may include an over-temperature protection sensor, which can trip and shut down the power supply at a preset temperature point. Such an overheated condition is typically the result of internal current overloading or a cooling fan failure. If the protection circuit is nonlatching, then it should have hysteresis built in to avoid intermittent tripping.

  • Page 28: Mechanical

    Version 2.0 4. Mechanical 4.1. Labeling / Marking The following is a non-inclusive list of suggested markings for each power supply unit. Product regulation stipulations for sale into various geographies may impose additional labeling requirements. • Manufacturer information: manufacturer’s name, part number, and lot date code, etc., in human-readable text and/or bar code formats •...

  • Page 29: Figure 8. Power Supply Dimensions For Chassis That Does Not Require Top Venting

    16.0 be flush mounted. Figure 8. Power Supply Dimensions for Chassis That Does Not Require Top Venting ATX12V Power Supply Design Guide Air inlet grill, 55% open area. 150 REF 4.0X6 (2X) 146.0...

  • Page 30: Figure 9. Power Supply Dimensions For Chassis That Require Top Venting

    ATX12V Power Supply Design Guide Version 2.0 Second optional fan may be located in optional venting area or on topside. 11.0 x 5.0 cutouts (4X); min 6.0 clearance under cutout from inside top cover. Preferred location of manufacturer label No. 6-32 UNC-2B THREADED HOLE (4X) Notes;...

  • Page 31: Airflow / Fan

    Fan location/direction. In general, exhausting air from the system chassis enclosure via a power supply fan at the rear panel is the preferred, most common, and most widely applicable system-level airflow solution. Other solutions are permitted, including fans on the topside of figure 5 and the Wire harness side of figure 4 or 5.

  • Page 32: Ac Connector

    ATX12V Power Supply Design Guide Version 2.0 The ATX Specification offers two options for venting between the power supply and the system interior: • The venting shown in Figure 8 provides the most effective channeled airflow for the power supply itself, with little regard for directly cooling any system components. This venting method is nearly always used in conjunction with a fan that exhausts out the rear of the power supply.

  • Page 33: Figure 10. Atx12V Power Supply Connectors

    Figure 10. ATX12V Power Supply Connectors (Pin-side view, not to scale) ATX12V Power Supply Design Guide Version 2.0 +3.3V +3.3 +3.3 +3.3V +3.3V +3.3 - 12V PS_O PS_ON# PWR_ON PWR_ +5VSB +12V1 +12V +12V +12V1 +3.3V +3.3V Main Power Connector...

  • Page 34: Atx Main Power Connector

    ATX12V Power Supply Design Guide Version 2.0 4.5.1. ATX Main Power Connector ousing: 24 Pin Molex Mini-Fit Jr. PN# 39-01-2240 or Connector: MOLEX* h equivalent (Mating motherboard connector is Molex 44206-0007 or equivalent) 18 AWG is suggested for all wires except for the +3.3 V sense return wire, pin 11 (22 AWG).

  • Page 35: Power Connector

    (Mating motherboard connector is Molex 39-29-9042 or equivalent) Signal 4.5.3. Peripheral Connector(s) Connector: AMP 1-480424-0 or MOLEX 8981-04P or equivalent. Contacts: AMP 61314-1 or equivalent. Signal +12V1DC +5VDC ATX12V Power Supply Design Guide 18 AWG Wire Signal Black +12V2DC Black +12V2DC 18 AWG Wire Yellow...

  • Page 36: Serial Ata Power Connector

    ATX12V Power Supply Design Guide Version 2.0 4.5.4. Serial ATA Power Connector This is a required connector for systems with Serial ATA devices. The detailed requirements for the Serial ATA Power Connector can be found in the “Serial ATA: High Speed Serialized AT Attachment” specification, Section 6.3 “Cables and connector specification”.

  • Page 37: Environmental

    5. Environmental The following subsections define recommended environmental specifications and test parameters, based on the typical conditions to which an ATX12V power supply may be subjected during operation or shipment. 5.1. Temperature Operating ambient Non-operating ambient 5.2. Thermal Shock (Shipping) Non-operating 5.3.

  • Page 38: Mechanical Shock

    For power supplies designed for low noise, the following provides some general guidance. Guidelines Sound Power: The power supply assembly shall not produce a declared sound power level greater than 4.0 BA. Sound power determination is to be performed at 43C, 50% of maximum rated load, at sea level.

  • Page 39: Electromagnetic Compatibility

    6.1. Emissions The power supply shall comply with FCC Part 15, EN55022: 1998 and CISPR 22: 1997, meeting Class B for both conducted and radiated emissions with a 4 dB margin. Tests shall be conducted using a shielded DC output cable to a shielded load. The load shall be adjusted as follows for three tests: No load on each output;...

  • Page 40: Input Line Current Harmonic Content And Line Flicker

    Version 2.0 Final Review Copy 6.3. Input Line Current Harmonic Content and Line Flicker For sales in EU (European Union) or Japan the power supply shall meet the requirements of EN61000-3-2 Class D and the Guidelines for the Suppression of Harmonics in Appliances and General Use Equipment Class D for harmonic line current content at full rated power.

  • Page 41: Reliability

    ATX12V Power Supply Design Guide Version 2.0 Final Review Copy 7. Reliability 7.1. Component De-rating The de-rating process promotes quality and high reliability. All electronic components should be designed with conservative device de-ratings for use in commercial and industrial environments...

  • Page 42: Safety

    • The supply must be recognized for use in Information Technology Equipment including Electrical Business Equipment per UL 60950, 3rd edition, 2000. The certification must include external enclosure testing for the AC receptacle side of the power supply. (see Figures 8 and 9).

  • Page 43: International

    Cadmium should not be used in painting or plating. No quaternary salt electrolytic capacitors shall be used. Mercury shall not be used. The use of CFCs or HFCs shall not be used in the design or manufacturing process. ATX12V Power Supply Design Guide Version 2.0 Final Review Copy...

Table of Contents