LM3500TLX-21/NOPB National Semiconductor, LM3500TLX-21/NOPB Datasheet
LM3500TLX-21/NOPB
Specifications of LM3500TLX-21/NOPB
Related parts for LM3500TLX-21/NOPB
LM3500TLX-21/NOPB Summary of contents
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... In shutdown, the LM3500 completely dis- connects the input from output, creating total isolation and preventing any leakage currents from trickling into the LEDs. Typical Application Circuit © 2007 National Semiconductor Corporation Features ■ Synchronous rectification, high efficiency and no external schottky diode required ■ ...
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... Connection Diagram Ordering Information Maximum Order Number Output Voltage 16V LM3500TL-16 16V LM3500TLX-16 21V LM3500TL-21 21V LM3500TLX-21 Pin Description/Functions Pin Name A1 AGND Analog ground Analog and Power supply input PMOS source connection for synchronous rectification. OUT C2 V Switch pin. Drain connections of both NMOS and PMOS power devices. ...
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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 (LM3500-16)(Note 2) OUT V (LM3500-21)(Note 2) OUT V (Note 2) SW FB, SHDN, and NC Voltages Maximum Junction Temperature Lead Temperature (Note 3) ESD Ratings (Note 4) Human Body Model ...
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Symbol Parameter OVP Output Overvoltage Protection (LM3500-16) Output Overvoltage Protection (LM3500-21 Bias Current Vout OUT (LM3500-16) V Bias Current OUT (LM3500-21) I PMOS Switch Leakage VL Current (LM3500-16) PMOS Switch Leakage Current (LM3500-21) SHDN SHDN Low Threshold SHDN ...
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... IN OUT Note 3: For more detailed soldering information and specifications, please refer to National Semiconductor Application Note 1112: Micro SMD Wafer Level Chip Scale Package (AN-1112), available at www.national.com. Note 4: The human body model is a 100 pF capacitor discharged through a 1.5 kΩ resistor into each pin. The machine model is a 200 pF capacitor discharged directly into each pin ...
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LED Efficiency vs LED Current L = Coilcraft DT1608C-223, Efficiency = 100*( LED Efficiency vs LED Current L = Coilcraft DT1608C-223, Efficiency = 100*( LED Efficiency vs LED Current L = Coilcraft DT1608C-223, Efficiency = ...
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LED Efficiency Coilcraft DT1608C-223, Efficiency = 100*(P /( LED LED 20065769 4 LED Efficiency Coilcraft DT1608C-223, Efficiency = 100*(P /( LED LED 20065773 ...
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Switch Current Limit vs V Switch Current Limit vs Temperature LM3500-16, V OUT Switch Current Limit vs Temperature LM3500-21, V www.national.com : LM3500-16 IN 20065762 =12V 20065776 =8V OUT 20065792 8 Switch Current Limit vs Temperature LM3500-16, V =8V OUT ...
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Switch Current Limit vs Temperature LM3500-21, V =18V OUT 20065794 V DC Bias vs V Voltage: LM3500-16 OUT OUT 20065765 FB Voltage vs Temperature 20065766 Oscillator Frequency Bias vs V Voltage: LM3500-21 OUT OUT FB Voltage ...
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NMOS R DSON (I = 300mA) SW Typical V Ripple IN = 22Ω, V LM3500-16, 3 LEDs 3.0V LED IN 1) SW, 10V/div 100mA/div 100mV/div ...
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Typical V Ripple, OVP Functioning: LM3500-16 OUT V open circuit and equals approximately 15V DC, V OUT 200mV/div, AC OUT T = 1ms/div Typical V OUT 20065782 V open circuit and equals approximately 20V DC ...
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Operation The LM3500 utilizes a synchronous Current Mode PWM con- trol scheme to regulate the feedback voltage over almost all load conditions. The DC/DC controller acts as a controlled current source ideal for white LED applications. The LM3500 is internally ...
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Application Information ADJUSTING LED CURRENT The White LED current is set using the following equation: The LED current can be controlled using a PWM signal on the SHDN pin with frequencies in the range of 100Hz (greater than visible frequency ...
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Typical Peak Inductor Currents (mA) # LEDs LED Current (V) series 2 100 134 3 118 138 190 4 142 174 244 5 191 232 319 3 ...
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FIGURE 2. Evaluation Board Layout (2X Magnification) Top Layer FIGURE 3. Evaluation Board Layout (2X Magnification) Bottom Layer (as viewed from the top) 15 20065777 20065778 www.national.com ...
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FIGURE 4. 2 White LED Application FIGURE 5. Multiple 2 LED String Application 16 20065709 20065754 ...
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FIGURE 6. Multiple 3 LED String Application FIGURE 7. LM3500-21 5 LED Application 17 20065783 20065790 www.national.com ...
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www.national.com 18 ...
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Physical Dimensions inches (millimeters) unless otherwise noted For Ordering, Refer to Ordering Information Table X1 = 1.92mm (±0.03mm 1.92mm (±0.03mm 0.6mm (±0.075mm) 8-Bump Micro SMD Package (TL) NS Package Number TLA08SSA 19 www.national.com ...
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