LM2703MFX-ADJ/NOPB National Semiconductor, LM2703MFX-ADJ/NOPB Datasheet
LM2703MFX-ADJ/NOPB
Specifications of LM2703MFX-ADJ/NOPB
Related parts for LM2703MFX-ADJ/NOPB
LM2703MFX-ADJ/NOPB Summary of contents
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... LED applications for cellular phone back-lighting. The LM2703 can drive white LEDs from a single Li-Ion battery. Typical Application Circuit © 2006 National Semiconductor Corporation Features n 350mA, 0.7Ω, internal switch n Uses small surface mount components n Adjustable output voltage up to 21V n 2 ...
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... Connection Diagram Ordering Information Order Number Package Type LM2703MF-ADJ SOT23-5 LM2703MFX-ADJ SOT23-5 Pin Descriptions/Functions Pin Name GND SHDN SW(Pin 1): Switch Pin. This is the drain of the internal NMOS power switch. Minimize the metal trace area con- nected to this pin to minimize EMI. GND(Pin 2): Ground Pin. Tie directly to ground plane. ...
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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 Voltage FB Voltage SHDN Voltage Maximum Junction Temp (Note 2) Lead Temperature (Soldering 10 sec.) Vapor Phase (60 sec.) Electrical Characteristics Specifications in standard type face are for T Range (T = − ...
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Typical Performance Characteristics Enable Current vs V (Part Switching) Efficiency vs Load Current www.national.com IN 20030605 20030610 4 Disable Current (Part Not Switching) 20030606 Efficiency vs Load Current 20030611 ...
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Typical Performance Characteristics Efficiency vs Load Current Switch Current Limit vs V (Continued) 20030612 IN 20030614 5 SHDN Threshold 20030613 Switch DSON IN 20030615 www.national.com ...
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Typical Performance Characteristics FB Trip Point and FB Pin Current vs Temperature Step Response V = 20V 2.5V OUT IN 1) Load, 1mA to 10mA to 1mA 200mV/div, AC OUT 200mA/div, ...
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Operation V = 20V 2.5V OUT 20V/div Inductor Current, 200mA/div 200mV/div, AC OUT T = 4µs/div FIGURE 2. LM2703 Block Diagram FIGURE 3. Typical Switching Waveform 7 ...
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Operation (Continued) The LM2703 features a constant off-time control scheme. Operation can be best understood by referring to Figure 2 and Figure 3. Transistors Q1 and Q2 and resistors R3 and R4 of Figure 2 form a bandgap reference used ...
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Application Information (Continued) FIGURE 4. White LED Application FIGURE 5. Li-Ion 5V Application FIGURE 6. Li-Ion 12V Application 9 20030609 20030619 20030620 www.national.com ...
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Application Information www.national.com (Continued) FIGURE 12V Application 10 20030621 ...
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