LM3424BSTEVAL/NOPB National Semiconductor, LM3424BSTEVAL/NOPB Datasheet
LM3424BSTEVAL/NOPB
Specifications of LM3424BSTEVAL/NOPB
Related parts for LM3424BSTEVAL/NOPB
LM3424BSTEVAL/NOPB Summary of contents
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... Input Voltage IN TP8 SYNC Synchronization Input TP9 NTC Temp Sense Input TP10 PGND Power Ground © 2009 National Semiconductor Corporation National Semiconductor Application Note 1969 James Patterson August 21, 2009 Key Features • Input: 10V to 26V • Output LEDs at 1A • Thermal Foldback / Analog Dimming • ...
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Schematic www.national.com 2 30097079 ...
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LM3424 Pin Descriptions Pin Name Description 1 V Input Voltage Enable 3 COMP Compensation 4 CSH Current Sense High 5 RT Resistor Timing 6 nDIM Not DIM input 7 SS Soft-start 8 TGAIN Temperature Foldback Gain 9 ...
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Bill of Materials Qty Part ID 3 C1, C5, C23 4 C2, C3, C16, C18 4 C4, C6, C17, C19 2 C7, C22 C10 1 C11 1 C12 2 C13, C14 1 C15 1 D1 ...
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PCB Layout Top Layer Bottom Layer 5 30097084 30097085 www.national.com ...
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Design Procedure SPECIFICATIONS 3.5V LED r = 325 mΩ LED V = 24V 10V IN-MIN V = 70V IN-MAX f = 500 kHz 100 mV SNS ...
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INDUCTOR RIPPLE CURRENT Solve for L1: The closest standard inductor is 33 µH therefore Δi Determine minimum allowable RMS current rating: The chosen component from step 5 is: 6. OUTPUT CAPACITANCE Solve for The closest capacitance ...
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C Assume The chosen components from step 9 are: 10. INPUT CAPACITANCE Solve for the minimum minimize power supply interaction a 200% larger capaci- tance of approximately 20 ...
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OUTPUT OVLO Solve for R : OV2 The closest standard resistor is 499 kΩ therefore V Solve for R : OV1 The closest standard resistor is 15.8 kΩ making V The chosen components from step 14 are: Typical Waveforms ...
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Alternate Designs Alternate designs with the LM3429 evaluation board are pos- sible with very few changes to the existing hardware. The evaluation board FETs and diodes are already rated higher than necessary for design flexibility. The input UVLO, output OVP, ...
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