LM3405AXMY/NOPB National Semiconductor, LM3405AXMY/NOPB Datasheet
LM3405AXMY/NOPB
Specifications of LM3405AXMY/NOPB
Related parts for LM3405AXMY/NOPB
LM3405AXMY/NOPB Summary of contents
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... Brightness LEDs in series at 1A forward current, with the single LED forward voltage of approximately 3.7V. Additional features include user accessible EN/DIM pin for enabling and PWM dimming of LEDs, thermal shutdown, cycle-by-cycle current limit and over-current protection. Typical Application Circuit © 2008 National Semiconductor Corporation Features ■ V operating range 22V IN ■ ...
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Connection Diagrams 6-Lead SOT-23 Package NS Package Number MK06A Ordering Information Part Number Package Type LM3405AXMK TSOT-6 LM3405AXMKX TSOT-6 LM3405AXMY eMSOP8 LM3405AXMYX eMSOP8 SOT23-6 Pin Descriptions Pin(s) Name 1 BOOST 2 GND EN/DIM 5 VIN 6 SW ...
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... Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications Voltage Boost Voltage Boost to SW Voltage FB Voltage EN/DIM Voltage Junction Temperature ESD Susceptibility (Note 2) Storage Temperature Electrical Characteristics limits in boldface type apply over the junction temperature (T guaranteed through test, design, or statistical correlation ...
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Typical Performance Characteristics T = 25°C. A Efficiency vs LED Current (V Efficiency vs Input Voltage ( Temperature FB www.national.com Unless otherwise specified, V =5V) Efficiency vs Input Voltage (I IN 30015271 = 0.7A) Efficiency vs Input Voltage ...
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Current Limit vs Temperature 30015272 Quiescent Current vs Temperature 30015234 SOT23 R vs Temperature (V DS(ON) Startup Response to EN/DIM Signal (V = 15V 0.2A 3V) BOOST SW 30015230 30015268 www.national.com ...
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Block Diagram Application Information THEORY OF OPERATION The LM3405A is a PWM, current-mode controled buck switching regulator designed to provide a simple, high effi- ciency solution for driving LEDs with a preset switching fre- quency of 1.6MHz. This high frequency ...
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When the LM3405A starts up, internal circuitry from V plies a 20mA current to the BOOST pin, flowing out of the BOOST pin into C3. This current charges voltage suf- ficient to turn the switch on. The ...
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The fourth method can be used in an application which has an external low voltage rail can be charged through EXT D2 from V , independent of V EXT IN Again for best performance, ensure that the ...
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LED PWM DIMMING The LED brightness can be controlled by applying a periodic pulse signal to the EN/DIM pin and varying its frequency and/ or duty cycle. This so-called PWM dimming method controls the average light output by pulsing the ...
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The catch diode (D1) forward voltage drop and the voltage drop across the internal NMOS must be included to calculate a more accurate duty cycle. Calculate D by using the following formula: V can be approximated by ...
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Given the availability and quality of MLCCs and the expected output voltage of designs using the LM3405A, there is really no need to review other capacitor technologies. A benefit of ceramic capacitors is their ability to bypass high frequency noise. ...
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The gate charge loss is associated with the gate charge Q required to drive the switch The power loss required for operation of the internal circuitry ...
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... R1 LED1 1.5A, White LED FIGURE 14. V derived from V BOOST 5V Part Number LM3405A C3216X5R0J106M GRM319R71A105KC01D 0805YC103KAT2A GRM319R71A105KC01D = 10V MBRM110LT1G R CMDSH-3 SLF6028T-4R7M1R6 WSL2010R2000FEA LXK2-PW14 13 30015242 Manufacturer National Semiconductor TDK Murata AVX Murata ON Semiconductor Central Semiconductor TDK Vishay Lumileds www.national.com ...
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... R1 LED1 1.5A, White LED www.national.com FIGURE 15. V derived from V BOOST OUT ( V = 12V Part Number LM3405A ECJ-3YB1E106K GRM319R71A105KC01D 0805YC103KAT2A GRM319R71A105KC01D = 30V SS13 R CMDSH-3 SLF6028T-4R7M1R6 WSL2010R2000FEA LXK2-PW14 14 30015243 Manufacturer National Semiconductor Panasonic Murata AVX Murata Vishay Central Semiconductor TDK Vishay Lumileds ...
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... V through a Shunt Zener Diode (D3) BOOST 18V Part Number LM3405A ECJ-3YB1E106K GRM319R71A105KC01D 0805YC103KAT2A GRM319R71A105KC01D GRM219R71C104KA01D = 30V SS13 R CMDSH-3 BZX84C4V7 SLF6028T-6R8M1R5 WSL2010R2000FEA CRCW08051K91FKEA LXK2-PW14 15 30015244 Manufacturer National Semiconductor Panasonic Murata AVX Murata Murata Vishay Central Semiconductor Fairchild TDK Vishay Vishay Lumileds www.national.com ...
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... White LED www.national.com derived from V through a Series Zener Diode (D3) BOOST 15V Part Number LM3405A ECJ-3YB1E106K GRM319R71A105KC01D 0805YC103KAT2A GRM319R71A105KC01D = 30V SS13 R CMDSH-3 BZX84C11 SLF6028T-6R8M1R5 WSL2010R2000FEA LXK2-PW14 16 30015249 Manufacturer National Semiconductor Panasonic Murata AVX Murata Vishay Central Semiconductor Fairchild TDK Vishay Lumileds ...
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... V through a Series Zener Diode (D3) BOOST OUT ( V = 18V Part Number LM3405A ECJ-3YB1E106K GRM319R71A105KC01D 0805YC103KAT2A GRM319R71A105KC01D = 30V SS13 R CMDSH-3 BZX84C3V6 SLF6028T-6R8M1R5 WSL2010R2000FEA LXK2-PW14 LXK2-PW14 17 30015250 Manufacturer National Semiconductor Panasonic Murata AVX Murata Vishay Central Semiconductor Fairchild TDK Vishay Lumileds Lumileds www.national.com ...
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... IN F Part Number LM3405A ECJ-3YB1E106K GRM319R71A105KC01D 0805YC103KAT2A ECE-A1EN221U = 30V SS13 R CMDSH-3 CMHSH5-2L CMHSH5-2L CMHSH5-2L CMHSH5-2L SLF6028T-6R8M1R5 ERJ8BQFR27 LXHL-PW09 18 30015251 Manufacturer National Semiconductor Panasonic Murata AVX Panasonic Vishay Central Semiconductor Central Semiconductor Central Semiconductor Central Semiconductor Central Semiconductor TDK Panasonic Lumileds ...
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Physical Dimensions inches (millimeters) unless otherwise noted 6-Lead TSOT Package NS Package Number MK06A 8-Lead eMSOP Package NS Package Number MUY08A 19 www.national.com ...
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