LM5008AEVAL/NOPB National Semiconductor, LM5008AEVAL/NOPB Datasheet
LM5008AEVAL/NOPB
Specifications of LM5008AEVAL/NOPB
Related parts for LM5008AEVAL/NOPB
LM5008AEVAL/NOPB Summary of contents
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... R1 and VIN according to the equation: The on-time of this evaluation board ranges from ≊ VIN = 8V, to 517 ns at VIN = 75V. The on-time varies in- versely with VIN to maintain a nearly constant switching fre- © 2010 National Semiconductor Corporation National Semiconductor Application Note 1925 Dennis Morgan March 25, 2010 • ...
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Board Layout and Probing The pictorial in Figure 1 shows the placement of the circuit components. The following should be kept in mind when the board is powered: 1) When operating at high input voltage and high load current, forced ...
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Option B) Intermediate Ripple Configuration: This config- uration generates less ripple at V than option A above by OUT Since the output ripple is passed by Cff to the FB pin with little or no attenuation, R5 can be reduced ...
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Current Limit Off-Time When current limit is detected the on-time period is immedi- ately terminated, and the off-time forced by the LM5008A must be greater than the maximum normal off-time, which occurs at maximum input voltage. The longer-than-normal off-time is ...
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... R5 Resistor R6 Resistor U1 Switching Regulator Mfg., Part Number TDK C1608X7R1H103M Vishay CRCW06032803F Vishay CRCW06037153F Vishay CRCW06033011F Panasonic ERJ-3RQFR82V Vishay CRCW08050000Z National Semiconductor LM5008AMM 5 Package Value 1206 1 µF, 100V 1210 22 µF, 16V 0603 0.47 µF, 16V 0603 0.01 µF, 50V 0805 0.1 µF, 100V ...
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Circuit Performance www.national.com FIGURE 6. Efficiency vs Load Current FIGURE 7. Efficiency vs Input Voltage 6 30086310 30086311 ...
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FIGURE 8. Output Voltage Ripple FIGURE 9. Switching Frequency vs. Input Voltage 7 30086312 30086313 www.national.com ...
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FIGURE 10. Current Limit vs Input Voltage FIGURE 11. Line Regulation 8 30086314 30086320 ...
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FIGURE 12. Load Regulation 9 www.national.com ...
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Typical Waveforms Trace Pin Trace OUT Trace 4 = Inductor Current Vin = 12V, Iout = 200 mA Trace Pin Trace OUT Trace 4 = Inductor Current Vin ...
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Trace Pin Trace OUT Trace 4 = Inductor Current Vin = 12V, Iout = 0 mA FIGURE 15. Discontinuous Conduction Mode 11 30086322 www.national.com ...
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PC Board Layout www.national.com Board Silkscreen Board Top Layer 12 30086317 30086318 ...
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Board Bottom Layer (Viewed from Top) 13 30086319 www.national.com ...
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