ATX12V Power Supply Design Guide
Version 2.0
Table 4. Typical Power Distribution for a 300 W ATX12V Configuration
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| Min. | Max. | Peak |
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| Current | Current | Current |
Output | (amps) | (amps) | (amps) | |
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+12 V1DC | 1.0 | 8.0 | 10.0 | |
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+12 V2DC | 1.0 | 14.0 |
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+5 | VDC | 0.3 | 20.0 |
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+3.3 | VDC | 0.5 | 20.0 |
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VDC | 0.0 | 0.3 |
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+5 VSB | 0.0 | 2.0 | 2.5 | |
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Note: Total combined output of 3.3 V and 5 V is î:
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.
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| 300W Cross Regulation |
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| (5V rail + 3.3V rail vs. 12V1 +12V2) |
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| 120 |
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(w atts) | 100 |
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80 |
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er |
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p ow | 60 |
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| Combined Power |
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| (5V rail + 3.3V rail) | ||
3.3V | 40 |
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+ |
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5V | 20 |
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| 0 |
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| 0 | 20 | 40 | 60 | 80 | 100 | 120 | 140 | 160 | 180 | 200 | 220 | 240 | 260 | 280 |
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| 12V power (watts) |
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Figure 2. Cross Loading Graph for 300W Configuration
14
