LM3429BSTEVAL/NOPB National Semiconductor, LM3429BSTEVAL/NOPB Datasheet
LM3429BSTEVAL/NOPB
Specifications of LM3429BSTEVAL/NOPB
*LM3429BSTEVAL/NOPB
LM3429BSTEVAL
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LM3429BSTEVAL/NOPB Summary of contents
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... Note that design modifications can change the system effi- ciency for better or worse. See the LM3429 datasheet for a comprehensive explanation of the device and application in- formation. Schematic © 2009 National Semiconductor Corporation National Semiconductor Application Note 1986 James Patterson August 3, 2009 EFFICIENCY WITH 9 SERIES LEDS AT 1A ...
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Pin Descriptions Pin Name Description 1 V Input Voltage IN 2 COMP Compensation 3 CSH Current Sense High 4 RCT Resistor Capacitor Timing 5 AGND Analog Ground 6 OVP Over-Voltage Protection 7 nDIM Not DIM input Connection ...
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Bill of Materials Qty Part C2, C3, C16, C18 3 C6, C17, C19 C12 J1, J2, J4 ...
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PCB Layout www.national.com 30100903 Top Layer 30100904 Bottom Layer 4 ...
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Design Procedure Refer to LM3429 datasheet for design considerations. SPECIFICATIONS 3.5V LED r = 325 mΩ LED V = 24V 10V 27V IN-MIN IN-MAX f = 700 kHz SW V ...
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OUTPUT CAPACITANCE Solve for total value of 6.6 µF (using 3 2.2 µF X7R ceramic capaci- tors) is chosen therefore the actual Δi Determine minimum allowable RMS current rating: The chosen components from step 5 ...
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NFET Determine minimum Q1 voltage rating and current rating: A 100V NFET is chosen with a current rating of 40A due to the low mΩ. Determine I DS-ON T-RMS The chosen component from step 9 is: ...
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Typical Waveforms T = +25° 24V and V = 31.5V STANDARD OPERATION TP1 switch node voltage (V LED current (I Alternate Designs Alternate designs with the LM3429 evaluation board are pos- sible with very few ...
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