LM3409EVAL National Semiconductor, LM3409EVAL Datasheet
LM3409EVAL
Specifications of LM3409EVAL
Related parts for LM3409EVAL
LM3409EVAL Summary of contents
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... This board can be easily modified to demonstrate other op- erating points as shown in the Alternate Designs section. The LM3409/09HV datasheet Design Procedure can be used to design for any set of specifications. Schematic © 2009 National Semiconductor Corporation National Semiconductor Application Note 1954 James Patterson November 20, 2009 ...
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Pin Descriptions Pin(s) Name Description 1 UVLO Input under-voltage lockout 2 IADJ Analog LED current adjust 3 EN Logic level enable 4 COFF Off-time programming 5 GND 6 PGATE 7 CSN Negative current sense 8 CSP Positive current sense 9 ...
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PCB Layout Top Layer Bottom Layer 3 30093650 30093651 www.national.com ...
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Design Procedure SPECIFICATIONS V = 24V 42V IN IN-MAX V = 15V 525kHz LED Δi = Δi = 450mA LED-PP L-PP Δv = 720mV IN- 10V 1.1V ...
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P-CHANNEL MOSFET Determine minimum Q1 voltage rating and current rating: A 70V, 5.7A PFET is chosen with R DS-ON 20nC. Determine I and P : T-RMS T The chosen component from step 6 is: 7. RE-CIRCULATING DIODE Determine minimum ...
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PWM DIMMING / SHUTDOWN METHOD The LM3409 demonstration board allows for PWM dimming and low power shutdown to be evaluated. The desired method is chosen as follows: Method # PWM dimming is desired, a jumper should be ...
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Alternate Designs Alternate designs with the LM3409 demonstration board are possible 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 can re- main ...
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