LM3406HVMH National Semiconductor, LM3406HVMH Datasheet
LM3406HVMH
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LM3406HVMH 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 © 2008 National Semiconductor Corporation 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 feedback pin 7 GND 8 DIM Input for PWM dimming ...
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... Absolute Maximum Ratings LM3406/LM3406HV (Note 1) 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 ...
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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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V voltage minus the diode drop to drive the MOSFET CC when its source voltage is equal FAST LOGIC PIN FOR PWM DIMMING The DIM pin is a TTL compatible input for PWM dimming of ...
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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 and the rest of the circuit increase. INPUT CAPACITORS Input capacitors at the VIN pin of the LM3406/06HV are se- lected using requirements for minimum capacitance and rms ripple current. The ...
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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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The peak LED/inductor current is then estimated. This calcu- lation uses the worst-case ripple current which occurs with three LEDs. + 0.5 x Δ L(PEAK) L L(MAX 1.5 + 0.5 x 0.56 = 1.78A L(PEAK) ...
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RECIRCULATING DIODE The input voltage of 24V ±5% requires Schottky diodes with a reverse voltage rating greater than 30V. The next highest standard voltage rating is 40V. Selecting a 40V rated diode provides a large safety margin for the ringing ...
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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 peak LED/inductor current is then estimated. This calcu- lation uses the worst-case ripple current which occurs MAX + 0.5 x Δ L(PEAK 1.5 + 0.5 x 0.516 = 1.76A L(PEAK) ...
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I = 1.5 x Sqrt(0.5 x 0.5) = 750 mA IN-RMS Ripple current ratings for 1210 size ceramic capacitors are typically higher than 2A, so two of them in parallel can tolerate more than enough for this design. RECIRCULATING DIODE ...
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FIGURE 11. Buck Converter Current Loops The dark grey, inner loop represents the high current path during the MOSFET on-time. The light grey, outer loop rep- resents the high current path during the off-time. GROUND PLANE AND SHAPE ROUTING 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 22 ...
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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 24 ...
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Notes 25 www.national.com ...
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