LM3503SQX-44 National Semiconductor Corporation, LM3503SQX-44 Datasheet
LM3503SQX-44
Related parts for LM3503SQX-44
LM3503SQX-44 Summary of contents
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... LM3503 offers superior performance over other step-up white LED drivers. Features n Drives White LEDs for Dual Display Backlighting Typical Application © 2005 National Semiconductor Corporation > 80% Peak Efficiency n n Output Voltage Protection Options: 16V, 25V, 35V & 44V n Input Under-Voltage Protection ...
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Connection Diagrams 10-Bump Thin MicroSMD Package (TLP10) Top View www.national.com 16-Lead Thin Leadless Leadframe Package (SQA16A) 20128602 2 20128603 Top View ...
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Pin Descriptions/Functions Bump # Pin # Name A1 9 Cntrl OUT2 OUT1 D2 2 and and 16 Pgnd C3 14 Agnd ...
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... L00047B 35 LM3503SQX-35 L00047B 44 LM3503ITL-44 SDNB 44 LM3503ITLX-44 SDNB 44 LM3503SQ-44 L00053B 44 LM3503SQX-44 L00053B www.national.com Package Marking 250 Units, Tape-and-Reel 3000 Units, Tape-and-Reel 1000 Units, Tape-and-Reel 4500 Units, Tape-and-Reel 250 Units, Tape-and-Reel 3000 Units, Tape-and-Reel 1000 Units, Tape-and-Reel 4500 Units, Tape-and-Reel 250 Units, Tape-and-Reel ...
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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. V Pin IN Sw Pin Fb Pin Cntrl Pin V Pin OUT1 V Pin OUT2 En1 En2 Continuous Power ...
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Electrical Characteristics typeface apply over the full operating junction temperature range (−40˚C ≤ T 2.5V. (Continued) Symbol Parameter I V Pin Bias V V OUT1(ON) OUT1 Current (Note Pin Leakage Fb = En1 = ...
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Block Diagram FIGURE 1. Block Diagram 7 20128604 www.national.com ...
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Detailed Description of Operation The LM3503 utilizes an asynchronous current mode pulse- width-modulation (PWM) control scheme to regulate the feedback voltage over specified load conditions. The DC/DC converter behaves as a controlled current source for white LED applications. The operation ...
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Typical Performance Characteristics D=B150-13. Efficiency: η [(V OUT IN I (Non-Switching (Switching LED Efficiency vs LED Current (See Typical Application Circuit : L=DO1608C-223 and – ...
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Typical Performance Characteristics D=B150-13. Efficiency: η OUT 6 LED Efficiency vs LED Current Cntrl Pin Current vs Cntrl Pin Voltage En1 Pin Current vs En1 Pin Voltage www.national.com (See Typical Application Circuit : L=DO1608C-223 and = ...
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Typical Performance Characteristics D=B150-13. Efficiency: η [(V OUT IN V Pin Current vs V OUT1 OUT1 NMOS R (Figure 1: N2 DS(ON) Feedback Voltage vs Cntrl Pin Voltage (See Typical Application Circuit : ...
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Typical Performance Characteristics D=B150-13. Efficiency: η OUT Current Limit (LM3503-16 Current Limit (LM3503-25 Current Limit (LM3503-35/44 www.national.com (See Typical Application Circuit : L=DO1608C-223 and = [(V – ...
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Typical Performance Characteristics D=B150-13. Efficiency: η [(V OUT IN Feedback Voltage (V = 1.6V) vs Temp Cntrl V = 3.6V at 15mA & 2 Leds IN (See Typical Application Circuit : L=DO1608C-223 and – V ...
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Application Information WHITE LED CURRENT SETTING The white LED current is controlled voltage at the Cntrl pin. The relationship between the Cntrl pin voltage and Fb pin voltage can be computed with the following Cntrl ...
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Application Information PWM Dimming Duty Cycle vs. LED Current The results are based on the 2LEDs on Main display and 2LEDs on Sub display Duty 200Hz 500Hz (%) R = 787k ohms R =316k ohms 10 0.78mA 1.59mA 20 1.85mA ...
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Application Information Fs: Switching Frequency White LED Current/Load Current. OUT L: Inductance Magnitude/Inductor Value. D: Duty Cycle for CCM operation. : Inductor Ripple Current. ∆ (avg): Average Inductor Current. L For CCM operation, the duty cycle ...
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Application Information the LM3503’s proper operation, and reduces the effect of the LM3503 on other devices sharing the same supply voltage. To ensure low input voltage ripple, the input capacitor must have an extremely low ESR result of ...
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Application Information directly effects output voltage ripple and efficiency. The cur- rent setting resistor, R1, should be kept close to the Fb pin to minimize copper trace connections that can inject noise into the system. The ground connection for the ...
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Physical Dimensions inches (millimeters) unless otherwise noted TLP10: 10-Bump Thin Micro SMD Package X1 = 1.958 2.135 0 Package Number TLP10 16-Lead Thin Leadless Leadframe Package NS Package Number SQA16A 19 www.national.com ...
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National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications. For the most current product information ...