551600003-001A National Semiconductor, 551600003-001A Datasheet

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... LEDs of varying number and type, LED dimming by pulse width modulation (PWM), broken/open LED protection, low-power shutdown and ther- mal shutdown complete the feature set. Typical Application © 2010 National Semiconductor Corporation LM3402/LM3402HV Features ■ Integrated 0.5A N-channel MOSFET ■ ...

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Connection Diagrams 8-Lead Plastic MSOP-8 Package NS Package Number MUA08A Ordering Information Order Number Package Type LM3402MM LM3402MMX MSOP-8 LM3402HVMM LM3402HVMMX LM3402MR LM3402MRX PSOP-8 LM3402HVMR LM3402HVMRX Pin Descriptions Pin(s) Name Description BOOT MOSFET drive bootstrap pin 3 ...

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... Absolute Maximum Ratings (LM3402) (Note 1) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. VIN to GND BOOT to GND SW to GND BOOT to VCC BOOT to SW VCC to GND DIM to GND CS to GND RON to GND Junction Temperature Storage Temp ...

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... Absolute Maximum Ratings (LM3402HV) (Note 1) If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. VIN to GND BOOT to GND SW to GND BOOT to VCC BOOT to SW VCC to GND DIM to GND CS to GND RON to GND Junction Temperature www ...

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Electrical Characteristics for +25°C. (Note 4) Limits appearing in boldface type apply over full Operating Temperature Range. Datasheet min/max A J specification limits are guaranteed by design, test, or statistical analysis. LM3402 Symbol Parameter SYSTEM PARAMETERS ...

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Symbol Parameter DIM COMPARATOR V Logic High IH V Logic Low IL I DIM Pull-up Current DIM-PU N-MOSFET AND DRIVER R Buck Switch On Resistance DS-ON V BOOT Under-voltage Lock-out DR-UVLO Threshold V BOOT Under-voltage Lock-out DR-HYS Hysteresis THERMAL SHUTDOWN ...

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Typical Performance Characteristics V vs Temperature (V REF LM3402HV (T REF IN Current Limit LM3402 ( 24V) IN 20192129 = 25°C) Current Limit vs Temperature (V A 20192131 = 25°C) Current ...

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100 kΩ 25° LM3402HV 25°C) A www.national.com , IN = 25°C) A 20192135 , IN 20192137 20192138 ...

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LM3402 O-MAX 25°C) A 20192140 LM3402HV O-MAX 25°C) A 20192142 LM3402 O-MIN 25° LM3402HV ...

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Block Diagram Application Information THEORY OF OPERATION The LM3402 and LM3402HV 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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The LM3402/02HV regulators should be operated in contin- uous conduction mode (CCM), where inductor current stays positive throughout the switching cycle. During steady-state operationin the CCM, the converter maintains a constant switching frequency, which can be selected using the follow- ...

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HIGH VOLTAGE BIAS REGULATOR The LM3402/02HV contains an internal linear regulator with a 7V output, connected between the VIN and the VCC pins. The VCC pin should be bypassed to the GND pin with a 0.1 µF ceramic capacitor connected ...

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LOW POWER SHUTDOWN The LM3402/02HV can be switched to a low power state ( µA) by grounding the RON pin with a signal-level SD MOSFET as shown in Figure 3. Low power MOSFETs like the 2N7000, 2N3904, or ...

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Design Considerations SWITCHING FREQUENCY Switching frequency is selected based on the tradeoffs 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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INPUT CAPACITORS Input capacitors at the VIN pin of the LM3402/02HV are se- lected using requirements for minimum capacitance and rms ripple current. The input capacitors supply pulses of current approximately equal to I while the power MOSFET is on, ...

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DIM mode is also application de- pendent. It will not affect regular PWM dimming operation. The fix for this issue is extremely simple. Place a resistor from the SW pin to ground according to the chart below. ...

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FIGURE 7. CS Pin, Transient Path with Protection 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 ...

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FIGURE 9. CS Pin with OVP, Transient Path with Protection 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 ...

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LC tank circuit) and causes voltages at the VIN pin to rise well in excess of both V and the voltage at the module input connector as clamped IN by the input TVS. If the ...

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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 or other transients. These series resistors limit the ...

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To select R the expression relating the Controlled On-time Overview section can be re-written as: Minimum on-time occurs at the maximum V 110% = 26.4V therefore calculated as (300 ...

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To select the proper output capacitor the equation from Buck Regulators with Output Capacitors is re-arranged to yield the following: The target tolerance for LED ripple current is ± and the LED datasheet gives ...

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DCR loss the inductor DCR = 0. 0.096 = 11 Recirculating diode loss 119 mW D Current Sense Resistor Loss ...

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I = 0.35 + 0.027 = 377 mA L(PEAK) In the case of a short circuit across the LED array, the LM3402HV will continue to deliver rated current through the short but will reduce the output voltage to equal the ...

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DCR loss the inductor DCR = 0. 1.1 = 135 Recirculating diode loss Current Sense Resistor Loss ...

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ID Part Number U1 LM3402 L1 SLF7045T-330MR82 D1 CMHSH5-4 Cf VJ0805Y104KXXAT Cb VJ0805Y103KXXAT Cin C3216X7R1H105M Co C2012X7R1A225M Rsns ERJ6BQFR75V Ron CRCW08055902F ID Part Number U1 LM3402HV L1 DO5022P-684 D1 CMMSH1-100 Cf VJ0805Y104KXXAT Cb VJ0805Y103KXXAT Cin C4532X7R2A225M Rsns ERJ6BQFR56V Ron CRCW08051214F ...

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Physical Dimensions inches (millimeters) unless otherwise noted 8-Lead MSOP Package NS Package Number MUA08A 8-Lead PSOP Package NS Package Number MRA08B 27 www.national.com ...

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