LM2705MFX-ADJ/NOPB National Semiconductor, LM2705MFX-ADJ/NOPB Datasheet
LM2705MFX-ADJ/NOPB
Specifications of LM2705MFX-ADJ/NOPB
Related parts for LM2705MFX-ADJ/NOPB
LM2705MFX-ADJ/NOPB 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 © 2010 National Semiconductor Corporation LM2705 Features ■ 150mA, 0.7Ω, internal switch ■ ...
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... Connection Diagram Ordering Information Order Number Package Type LM2705MF-ADJ SOT23-5 LM2705MFX-ADJ SOT23-5 Pin Descriptions/Functions Pin Name 1 SW Power Switch input. 2 GND Ground Output voltage feedback input. 4 SHDN Shutdown control input, active low Analog and Power input. IN SW(Pin 1): Switch Pin. This is the drain of the internal NMOS power switch ...
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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.) 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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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 100mA/div ...
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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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The LM2705 features a constant off-time control scheme. Operation can be best understood by referring to Figure 3. Transistors Q1 and Q2 and resistors R3 and R4 of Figure 2 form a bandgap reference used to control the output voltage. ...
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Copt / Ropt included www.national.com 20039749 FIGURE 4. Output Ripple Voltage 20039709 FIGURE 5. 2 White LED Application and Efficiency 8 Copt / Ropt excluded 20039750 20039742 ...
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FIGURE 6. 3 White LED Application and Efficiency FIGURE 7. Li-Ion 12V Application 9 20039743 20039735 www.national.com ...
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FIGURE 12V Application FIGURE 9. 3.3V SEPIC Application 10 20039736 20039739 ...
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FIGURE 10. 5V SEPIC Application 11 20039740 www.national.com ...
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Physical Dimensions www.national.com inches (millimeters) unless otherwise noted 5-Lead Small Outline Package (M5) For Ordering, Refer to Ordering Information Table NS Package Number MA05B 12 ...
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Notes 13 www.national.com ...
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