LM5072EVAL National Semiconductor, LM5072EVAL Datasheet
LM5072EVAL
Specifications of LM5072EVAL
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LM5072EVAL Summary of contents
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... PoE input UVLO hysteresis: 7V nominal This application note focuses on the evaluation board. Please refer to the datasheet for detailed information about the complete functions and features of the LM5072 IC. © 2006 National Semiconductor Corporation National Semiconductor Application Note 1455 Youhao Xi March 2006 ...
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Connection and Proper Test Methods FIGURE 2. LM5072 Evaluation Board Connections Figure 2 shows the connections for the LM5072 evaluation board. The LM5072 evaluation board has the following four ports for connections. • J1, the RJ45 connector for PoE input ...
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Power Up (Continued) (+3.3V) and J5 (3.3V RTN), will allow direct measurement of the 3.3V output line. If the 3.3V output voltage is not ob- served within a few seconds, turn the power supply off and review connections. A final ...
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Input UVLO and UVLO Hysteresis The input Under Voltage Lock-Out (UVLO integrated function of the LM5072. The UVLO release threshold is set to approximately 38.5V (at the pins of the IC) and the UVLO hysteresis is approximately 7V. ...
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Auxiliary Input “OR-ing” Diode Selection (Continued) diodes and prevent false states at the ICL_FAUX and RAUX pins. Please see the LM5072 datasheet for more details about the selection of these two resistors. Flyback Converter Topology The dc-dc converter stage of ...
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Factors Limiting the Minimum Operating Input Voltage To optimize efficiency over the maximum input voltage range of 10.5V to 60V (9V min seen at the VIN pin, after R1 and R2 are replaced with 1Ω), a larger magnetic core like ...
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Performance Characteristics (Continued) Horizontal Resolution: 5 ms/Div. Trace 1: VOUT, cross-regulating VCC after output regulation is established. 2V/Div. Trace 2: VCC, first regulated by startup regulator at 7.6V, then elevated by auxiliary winding to 11V. 2V/Div. Trace 3: Input Current, ...
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Performance Characteristics (Continued) Horizontal Resolution: 1 ms/Div. Trace 1: VOUT, 1V/Div. Trace 2: SS pin voltage (referenced to RTN), 1V/Div Trace 3: Input current (AC coupled), 200 mA/Div FIGURE 8. Output Voltage Vout (+3.3V) Soft-start Detail OUTPUT DEAD SHORT FAULT ...
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Performance Characteristics (Continued) STEP RESPONSE Figure 11 shows the step load response at Vin = 48V. Horizontal Resolution: 0.2 ms/Div. Trace 1: Output voltage (AC coupled), 200 mV/Div. Trace 2: Output current (DC coupled), 0.5 A/Div. FIGURE 11. Regulator Response ...
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Reconfiguration of the Evaluation Board for Non-Isolated Output For applications where output isolation is not required, the non-isolated version of the evaluation board can be used to reduce the BOM cost. Reconfiguration of the circuit board to the non-isolated version ...
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A Note For Using The Efficiency Optimized EP13 Power Transformer DA2383 Please note that the DA2383 is a single output transformer. When using a DA2383 to obtain better efficiency (See Figure 3 for the applicable load and AUX input voltage ...
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Appendix: LM5072 Evaluation Board Bill of Materials ITEM PART NUMBER Q1 SUD15N15-95 R1 CRCW2512200J R2 CRCW2512200J R3 CRCW080520R0F R4 CRCW120610R0F R5 CRCW08053321F R6 CRCW08051002F R7 CRCW080510R0F R9 CRCW08051000F R11 CRCW08051002F R12 CRCW08052432F R13 CRCW08054991F R14 CRCW12060R301F R15 CRCW12060R301F R16 CRCW08051001F ...
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