LM5085EVAL National Semiconductor, LM5085EVAL Datasheet
LM5085EVAL
Specifications of LM5085EVAL
Related parts for LM5085EVAL
LM5085EVAL Summary of contents
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... LM5085 Evaluation Board Introduction The LM5085EVAL evaluation board provides the design en- gineer with a fully functional buck regulator, employing the LM5085 PFET switching controller which uses the constant on-time (COT) operating principle. This evaluation board pro- vides a 5V output over an input range of 5.5V to 55V. The circuit delivers load currents to 4.5A, with current limit set at ≊ ...
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Refer to the LM5085 data sheet for a detailed block diagram, and a complete description of the various functional blocks. Board Layout and Probing The pictorial in Figure 1 shows the placement of the circuit components. The following should be ...
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A) Sense resistor method – This evaluation board is sup- plied configured for the sense resistor method of current limit detection. Jumpers A-B are in place at both jumper locations (JP1, JP2), which connects the ADJ pin resistor (R3) and ...
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B) Reduced Ripple Level Configuration: This configuration generates more ripple at V than the above configuration, OUT but uses one less capacitor. If some ripple is acceptable in the application, this configuration is slightly more economical, and simpler. R6 and ...
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C) Lowest Cost Configuration: This configuration is the same as option B above, but with C5 removed. The ripple at the FB pin is attenuated from that at V ≥ resistors (R1, R2). Since 25 mVp-p are required at the ...
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... TKD C2012X7R2A332K On Semi MBRB2060CT Wurth XXL 7447709150 Vishay Si7465DP Vishay CRCW08051002F Vishay CRCW08053401F Vishay CRCW08051911F Vishay CRCW08059092F Vishay WSL2010R0100F Vishay CRCW08050000Z Vishay CRCW08052322F National Semiconductor LM5085MY 6 Package Value 2220 6.8 µF, 100V 1812 4.7 µF, 100V 0805 0.47 µF, 16V 0805 ...
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Circuit Performance FIGURE 10. Switching Frequency vs. Input Voltage 30072015 FIGURE 8. Efficiency vs Load Current 30072032 FIGURE 9. Efficiency vs Input Voltage 30072017 7 www.national.com ...
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FIGURE 11. Output Voltage Ripple 30072030 FIGURE 12. Line Regulation 8 ...
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FIGURE 13. Load Regulation 9 www.national.com ...
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Typical Waveforms Trace 4 = Inductor Current Trace OUT Trace Node V = 48V 1Amp IN OUT Minimum Ripple Configuration (Option A) Trace 4 = Inductor Current Trace OUT ...
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Trace 4 = Inductor Current Trace OUT Trace Node V = 48V OUT FIGURE 16. Discontinuous Conduction Mode (Expanded Scale) 30072021 11 www.national.com ...
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PC Board Layout www.national.com Board Silkscreen Board Top Layer Board Bottom Layer (Viewed from Top) 12 30072022 30072023 30072024 ...
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