TFX12V Power Supply Design Guide
Thin Form Factor with
Version 2.0
Contents
1 | Introduction | 7 | ||
| 1.1 | TFX12V Scope | 7 | |
| 1.2 | TFX12V Overview | 7 | |
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| 1.2.1 | Small System Optimized Profile | 7 |
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| 1.2.2 | Improved Acoustics | 8 |
| 1.3 | Key Changes for TFX12V Version 2.0 | 8 | |
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| 1.3.1 | Increased +12 VDC Output Capability | 8 |
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| 1.3.2 | Minimum Efficiency | 8 |
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| 1.3.3 | Main Power Connector | 8 |
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| 1.3.4 | Separate Current Limit for 12V2 on the 2x2 Connector | 8 |
| 1.4 | Terminology | 9 | |
2 | Electrical | ........................................................................................................ | 10 |
2.1AC Input 10
| 2.1.1 | Input Over Current Protection | 10 |
| 2.1.2 | Inrush Current Limiting | 10 |
| 2.1.3 | Input Under Voltage | 10 |
| 2.1.4 | Regulatory | 11 |
| 2.1.5 | Catastrophic Failure Protection | 12 |
2.2 | DC Output | 12 | |
| 2.2.1 | DC Voltage Regulation | 12 |
| 2.2.2 | Remote Sensing | 12 |
| 2.2.3 | Typical Power Distribution | 13 |
| 2.2.4 | Power Limit / Hazardous Energy Levels | 16 |
| 2.2.5 | Efficiency General | 16 |
| 2.2.6 | Other Low Power System Requirements | 18 |
| 2.2.7 | Output Ripple/Noise | 18 |
| 2.2.8 | Output Transient Response | 19 |
| 2.2.9 | Capacitive Load | 20 |
| 2.2.10 | 20 | |
| 2.2.11 | +5 VDC / +3.3 VDC Power Sequencing | 20 |
| 2.2.12 | Voltage | 20 |
2.3 Timing / Housekeeping / Control | 21 | ||
| 2.3.1 | PWR_OK | 22 |
| 2.3.2 | PS_ON# | 22 |
| 2.3.3 | +5 VSB | 23 |
| 2.3.4 | 23 | |
| 2.3.5 | Rise Time | 24 |
| 2.3.6 | Overshoot at | 24 |
| 2.3.7 | Reset after Shutdown | 24 |
| 2.3.8 | +5 VSB at AC | 24 |
2.4 | Output Protection | 24 | |
| 2.4.1 | Over Voltage Protection | 24 |
| 2.4.2 | 25 |
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