LM3406HVEVAL National Semiconductor, LM3406HVEVAL Datasheet
LM3406HVEVAL
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LM3406HVEVAL Summary of contents
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... LED dimming via pulse width modulation (PWM) is achieved using a dedicated logic pin or by PWM of the power input voltage. The product feature set is rounded out with low- power shutdown and thermal shutdown protection. Typical Application © 2010 National Semiconductor Corporation LM3406/06HV Features ■ Integrated 2.0A MOSFET ■ ...
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Connection Diagram Ordering Information Order Number Package Type LM3406MH LM3406MHX eTSSOP-14 LM3406HVMH LM3406HVMHX Pin Descriptions Pin(s) Name Description 1 BOOT MOSFET drive bootstrap pin Connect 5 VOUT Output voltage sense pin 6 CS Current sense ...
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... Absolute Maximum Ratings LM3406/LM3406HV (Note If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. VIN to GND VINS to GND VOUT to GND BOOT to GND SW to GND BOOT to VCC BOOT to SW VCC to GND DIM to GND Electrical Characteristics ...
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Symbol Parameter V V Under-voltage Lock-out CC-UV-TH CC Threshold V V Under-voltage Lock-out CC-UV-HYS CC Hysteresis I I Operating Current IN- Shutdown Current IN-SD IN CURRENT LIMIT I Current Limit Threshold LIM DIM COMPARATOR V Logic High ...
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Typical Performance Characteristics Efficiency Vs. Number of InGaN LEDs in Series (Note Temperature REF LM3406HV REF IN Efficiency Vs. Output Current 30020363 V REF 30020335 Current Limit vs Temperature 30020337 5 (Note 6) ...
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Current Limit www.national.com , LM3406 IN 30020339 IN 30020341 6 Current Limit LM3406HV IN 30020340 LM3406 O-MAX IN 30020342 ...
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Block Diagram Application Information THEORY OF OPERATION The LM3406 and LM3406HV are buck regulators with a wide input voltage range, low voltage reference, and a fast output enable/disable function. These features combine to make them ideal for use as a ...
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FIGURE 1. Comparator and One-Shot SWITCHING FREQUENCY The LM3406/06HV does not contain a clock, however the on- time is modulated in proportion to both input voltage and output voltage in order to maintain a relatively constant fre- quency. On-time t ...
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INTERNAL MOSFET AND DRIVER The LM3406/06HV features an internal power MOSFET as well as a floating driver connected from the SW pin to the ...
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PEAK CURRENT LIMIT The current limit comparator of the LM3406/06HV will engage whenever the power MOSFET current (equal to the inductor current while the MOSFET is on) exceeds 2.1A (typical). The power MOSFET is disabled for a cool-down time that ...
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FIGURE 4. Two Methods of Output Open Circuit Protection LOW POWER SHUTDOWN The LM3406/06HV can be placed into a low power state (I = 240 µA) by grounding the RON pin with a signal-level SD MOSFET as shown in Figure ...
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Design Considerations SWITCHING FREQUENCY Switching frequency is selected based on the trade-offs be- tween efficiency (better at low frequency), solution size/cost (smaller at high frequency), and the range of output voltage that can be regulated (wider at lower frequency.) Many ...
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... LED return connector terminal could be absorbed as calculated by: This is an extremely high energy event, so the protection measures previously described should be adequate to solve this issue – Diode datasheets will also provide a typical D , which can θ ...
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Adding a resistor in series with the CS pin causes the ob- served output LED current to shift very slightly. The reason for this is twofold: (1) the CS pin has about 20pF of inherent capacitance inside it which causes ...
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CS PIN PROTECTION WITH OVP When designing output overvoltage protection into the switch- ing converter circuit using a zener diode, transient protection on the CS pin requires additional consideration. As shown in Figure 9, adding a zener diode from the ...
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VIN PIN PROTECTION The VIN pin also has an ESD structure from the pin to GND with a breakdown voltage of approximately 80V. Any transient that exceeds this voltage may damage the device. Although transient absorption is usually present at ...
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FIGURE 12. VIN Pin with Additional Input Protection GENERAL COMMENTS REGARDING OTHER PINS Any pin that goes “off-board” through a connector should have series resistance of at least 1kΩ to 10kΩ in series with it to protect it from ESD ...
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R and moderate switching frequency of 500 kHz will balance the requirements of inductor size and overall power efficiency. The LM3406 will allow some shift in switching frequency when V changes due to the number of ...
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FIGURE 14. Calculating r from the V D Extending the tangent line to the ends of the plot yields values for ΔV and ΔI of 0.7V and 2000 mA, respectively. Dynamic F F resistance is then: = ΔV / ΔI ...
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AND The bootstrap capacitor C should always ceramic B capacitors with X7R dielectric. A 25V rating is appropriate for all application circuits. The COMP pin capacitor C linear regulator ...
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R and switching frequency of 450 kHz helps balance the require- ments of inductor size and overall power efficiency, but more importantly keeps the switching frequency below 530 kHz, where the AM radio band begins. This ...
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The most filtering (and therefore the highest output capaci- tance) is needed when ΔI is highest, which occurs Inductor ripple current with ...
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Gate charging and VCC loss the gate drive and linear G regulator IN- (600 4 ...
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FET produces a pulsating current just like the switching action of the LM3406's internal power FET and the Schottky diode. the path that the inductor current takes through the LED or through the ...
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ID Part Number U1 LM3406 L1 SLF10145T-220M1R-PF D1 CMSH2-40 Cc, Cf VJ0603Y104KXXAT Cb VJ0603Y223KXXAT Cin1 C4532X7R1H475M Cin2 Co C2012X7R1E105M Rsns ERJ14RQFR13V Ron CRCW08051433F ID Part Number U1 LM3406 L1 SLF10145T-150M2R2-P D1 CMSH2-60 Cc, Cf VJ0603Y104KXXAT Cb VJ0603Y223KXXAT Cin1 C3225X7R1H335M Cin2 ...
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Appendix The following expressions provide the best accuracy for users who wish to create computer-based simulations or circuit cal- culators: www.national.com 26 ...
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... Engineering Samples As a consideration for the right to sample preliminary pre- production devices prior to full qualification and production release ("Engineering Samples") by National Semiconductor Corporation, including its wholly-owned subsidiaries ("Nation- al"), user agrees to accept such Engineering Samples “AS IS” IN PRE-PRODUCTION FORM WITHOUT WARRANTY OF ANY KIND for the sole purpose of engineering evaluation and testing ...
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Physical Dimensions www.national.com inches (millimeters) unless otherwise noted 14-Lead Exposed Pad Plastic TSSOP Package NS Package Number MXA14A 28 ...
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Notes 29 www.national.com ...
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