LM5073MH/NOPB National Semiconductor, LM5073MH/NOPB Datasheet
LM5073MH/NOPB
Specifications of LM5073MH/NOPB
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LM5073MH/NOPB Summary of contents
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... Versatile Auxiliary Power Options ■ 13V Minimum Front Auxiliary Power Range ■ 9V Minimum Rear Auxiliary Power Range Simplified Application Diagram © 2010 National Semiconductor Corporation LM5073 ■ Programmable DC Current Limit up to 800 mA ■ 100V, 0.7Ω Hot Swap MOSFET ■ ...
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Connection Diagram Ordering Information Order Number LM5073MH LM5073MHX Pin Descriptions Pin Number Name 1 UVLORTN 2 UVLO 3 VIN 4 RCLASS 5 FAUX 6 DCCL 7 VEE RTN nPGOOD 12 nSD ...
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... Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. VIN, FAUX, UVLO, RTN to VEE (Note 6) UVLORTN to VEE DCCL, RCLASS to VEE nPGOOD, nSD RTN RAUX to RTN Electrical Characteristics over the junction temperature (T ) range of -40° ...
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... Note 2: The human body model is a 100 pF capacitor discharged through a 1.5 kΩ resistor into each pin. Note 3: For detailed information on soldering the plastic TSSOP package, refer to the Packaging Databook available from National Semiconductor. Note 4: Minimum and Maximum limits are guaranteed through test, design, or statistical correlation using Statistical Quality Control (SQC) methods. Typical values represent the most likely parametric norm at T Outgoing Quality Level (AOQL) ...
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Typical Performance Characteristics Default UVLO Threshold vs Temperature Inrush Current Limit vs Temperature Default DC Current Limit vs Temperature DC Current Limit vs. DCCL Resistor 30000203 Programmed DC Current Limit vs Temperature 30000205 Input Current vs Input Voltage 30000207 5 ...
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Block Diagram Description of Operation and Applications Information The LM5073 integrates a fully IEEE 802.3af compliant PD in- terface with versatile auxiliary power support. When com- bined with a separate DC-DC converter, it provides a complete power solution for Powered ...
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A power good flag pin allows an accurate power good delay to be programmed and provides the option of driving a power good indicator LED. 7. Input line over voltage protection for downstream circuits, including the DC-DC converter. DC-DC ...
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Detection Signature In the detection mode must present a signature resis- tance between 23.75 kΩ and 26.25 kΩ to the PoE power sourcing equipment. This signature impedance distinguishes the PD from non-PoE equipment to protect the latter from ...
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FIGURE 4. PD Classification – Fulfilled With a Single External Resistor Undervoltage Lockout (UVLO) The LM5073 contains both programmable and default input Under Voltage Lock Out (UVLO) circuits. the block diagram of the LM5073 UVLO circuit. When the UVLO pin ...
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FIGURE 5. Programmable and Default Input UVLO Functions Over-Voltage Protection To protect the downstream DC-DC converter from excessive voltage, the hot swap MOSFET is disabled when the 65V (nominal) over-voltage protection (OVP) threshold is exceed- ed. This allows the 100V ...
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The analysis should include evaluations of the dissipation ca- pability of LM5073 package, heat sinking properties of the PC board, ambient temperature, and other heat dissipation fac- tors of the operating environment. FIGURE 6. Input DC Current Limit Programming via ...
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The nPGOOD pin can also be used to implement a delay timer by adding a capacitor from the nPGOOD pin to the RTN pin. This delay timer will prevent the interruption of the DC-DC converter’s operation in the event of ...
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FIGURE 8. The FAUX Configuration FIGURE 9. The RAUX Configuration 13 30000219 30000220 www.national.com ...
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TABLE 3. Comparison Between FAUX and RAUX Operation Tradeoff Hot Swap Protection / Current Limit Protection Minimum Auxiliary Voltage (at the IC pins) Auxiliary Dominance Over PoE Use of nPGOOD Pin as “Powered from PoE” Indicator Transient Protection The term ...
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... It should be noted that rear auxiliary non-dominance does not imply PoE dominance. PoE dominance requires a different circuit configuration if continuity of power is desired. Please contact National Semiconductor for support on PoE dominant solutions. A Note About FAUX and RAUX Pin False Input State Detection The FAUX and RAUX pins are used to sense the presence of auxiliary power sources ...
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Application Examples The following are a few application examples. Figure 12 shows the LM5073 PD interface supporting front auxiliary power configuration. According to particular application re- quirements, users can select an appropriate DC-DC converter to optimize the PD design. National’s ...
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Figure 13 shows the LM5073 PD interface supporting rear auxiliary power configuration. Similarly, users can select a DC-DC converter to optimize the PD design. National’s LM5025/26 active clamp forward converter evaluation board is recommended for a high efficiency, isolated application; ...
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www.national.com 18 ...
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Physical Dimensions inches (millimeters) unless otherwise noted 14 Lead TSSOP-EP NS Package Number MXA14A 19 www.national.com ...
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