LM2705MF-ADJ National Semiconductor, LM2705MF-ADJ Datasheet
LM2705MF-ADJ
Specifications of LM2705MF-ADJ
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LM2705MF-ADJ Summary of contents
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... The LM2705 can drive white LEDs from a single Li-Ion battery. The low peak inductor current of the LM2705 makes it ideal for USB applications. Typical Application Circuit © 2003 National Semiconductor Corporation Features n 150mA, 0.7Ω, internal switch n Uses small surface mount components n Adjustable output voltage up to 20V n 2 ...
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... Connection Diagram Ordering Information Order Number Package Type LM2705MF-ADJ SOT23-5 LM2705MFX-ADJ SOT23-5 Pin Description/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 SHDN Threshold vs V www.national.com IN 20039705 20039724 IN 20039713 4 Disable Current (Part Not Switching) 20039706 Efficiency vs Load Current 20039725 Switch Current ...
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Typical Performance Characteristics Switch DSON Output Voltage vs Load Current Step Response V = 20V 3.0V OUT IN 1) Load, 0.5mA to 5mA to 0.5mA 200mV/div, AC OUT ...
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Operation V = 20V 2.7V 2.5mA OUT IN OUT 20V/div Inductor Current, 100mA/div 200mV/div, AC OUT T = 10µs/div www.national.com FIGURE 2. LM2705 Block Diagram 20039730 ...
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Operation (Continued) The LM2705 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 ground connection for the feedback network should tie di- www.national.com rectly to the GND pin. Trace connections made to the induc- (Continued) tor and schottky diode should be minimized to reduce power dissipation and increase overall efficiency. 20039709 ...
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Application Information (Continued) FIGURE 6. Li-Ion 12V Application FIGURE 12V Application 9 20039735 20039736 www.national.com ...
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Application Information www.national.com (Continued) FIGURE 8. 3.3V SEPIC Application FIGURE 9. 5V SEPIC Application 10 20039739 20039740 ...
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... NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT AND GENERAL COUNSEL OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant ...