LM3404MA National Semiconductor, LM3404MA Datasheet
LM3404MA
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LM3404MA Summary of contents
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... LED arrays of varying number and type. LED dimming via pulse width modulation (PWM), broken/open LED protection, low- power shutdown and thermal shutdown complete the feature set. Typical Application © 2010 National Semiconductor Corporation LM3404/04HV Features ■ Integrated 1.0A MOSFET ■ ...
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... Connection Diagrams 8-Lead Plastic SO-8 Package NS Package Number M08A Ordering Information Order Number Package Type LM3404MA LM3404MAX SO-8 LM3404HVMA LM3404HVMAX LM3404MR LM3404MRX PSOP-8 LM3404HVMR LM3404HVMRX Pin Descriptions Pin(s) Name Description BOOT MOSFET drive bootstrap pin 3 DIM Input for PWM dimming 4 GND ...
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... Absolute Maximum Ratings (LM3404) (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 (LM3404HV) (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 specification limits are guaranteed by design, test, or statistical analysis. LM3404 Symbol Parameter SYSTEM ...
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Symbol Parameter DIM COMPARATOR V Logic High IH V Logic Low IL I DIM Pull-up Current DIM-PU MOSFET AND DRIVER R Buck Switch On Resistance DS-ON V BST Under-voltage Lock-out DR-UVLO Threshold V BST Under-voltage Lock-out DR-HYS Hysteresis THERMAL SHUTDOWN ...
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Typical Performance Characteristics V vs Temperature (V REF LM3404HV (T REF IN Current Limit LM3404 ( 24V) IN 20205450 = 25°C) Current Limit vs Temperature (V A 20205452 = 25°C) Current ...
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100 kΩ 25° LM3404HV 25°C) A www.national.com , IN = 25°C) A 20205435 , IN 20205437 20205438 ...
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LM3404 O-MAX 25°C) A 20205440 LM3404HV O-MAX 25°C) A 20205442 LM3404 O-MIN 25° LM3404HV ...
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Block Diagram Application Information THEORY OF OPERATION The LM3404 and LM3404HV 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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CCM operation, the converter maintains a constant switching frequency that can be selected using the following equation forward voltage of each LED number of LEDs in F series AVERAGE LED CURRENT ACCURACY The COT architecture regulates ...
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V exceeds 300 mV. This threshold provides a hard limit SNS for the output current. Output current overshoot is limited to 300 this comparator during transients. SNS The OVP/OCP comparator can also be used to prevent ...
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THERMAL SHUTDOWN Internal thermal shutdown circuitry is provided to protect the IC in the event that the maximum junction temperature is ex- ceeded. The threshold for thermal shutdown is 165°C with a 25°C hysteresis (both values typical). During thermal shut- ...
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Small values also be used to control EMI generated by the switching action of the LM3404/04HV. EMI reduction becomes more important as the length of the connections between the LED and ...
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Consequently, with a maxi- mum Vcc voltage of 7.4V, current will be observed in the LEDs if the total stack voltage is less than about forward current of several microamps. No current is ...
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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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FIGURE 8. CS Pin with OVP, Transient Path FIGURE 9. CS Pin with OVP, Transient Path with Protection 17 20205459 20205460 www.national.com ...
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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 11. 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 is needed in this application to balance the requirements of magnetics size and efficiency selected from the equation for switching frequency as ON follows 7.1 / (1.34 ...
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R SNS A preliminary value for R was determined in selecting SNS Δi . This value should be re-evaluated based on the calcula- L tions for Δ 0.33Ω 220 ns, R SNS SNS Sub-1Ω resistors ...
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Design Example 2: LM3404HV The second example circuit will guide the user through com- ponent selection for an outdoor general lighting application. A regulated DC voltage input of 48V ±10% will power ten se- R and ...
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The inductor ripple current and peak cur- rent in this condition would be equal to: Δi = [(48 – 0. L(LED-SHORT) = 0.598A P 0.5 + 0.5 x 0.598 = ...
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C AND The bootstrap capacitor C should always ceramic B capacitor with X7R dielectric. A 25V rating is appropriate for all application circuits. The linear regulator filter capacitor C should always be a ...
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PCB. Multiple vias in parallel should be used right at the pad of the input capacitor to connect the component side shapes to the ground plane. A ...
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ID Part Number U1 LM3404 L1 SLF10145T-470M1R4 D1 CMSH2-40 Cf VJ0805Y104KXXAT Cb VJ0805Y103KXXAT Cin C3225X7R1H335M Co C2012X7R1E105M Rsns ERJ8BQFR33V Ron CRCW08051333F ID Part Number U1 LM3404HV L1 DO5022P-334 D1 CMSH1-60M Cf VJ0805Y104KXXAT Cb VJ0805Y103KXXAT Cin C4532X7R2A225M Co C3216X7R2A154M Rsns ERJ6BQFR43V ...
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Physical Dimensions inches (millimeters) unless otherwise noted SO-8 Package NS Package Number M08A PSOP-8 Package NS Package Number MRA08B 27 www.national.com ...
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