LM2731YMF National Semiconductor, LM2731YMF Datasheet
LM2731YMF
Specifications of LM2731YMF
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LM2731YMF Summary of contents
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... Internal compensation simplifies de- sign and reduces component count. Switch Frequency X 1.6 MHz 0.6 MHz Typical Application Circuit © 2010 National Semiconductor Corporation LM2731 Features ■ 22V DMOS FET switch ■ 1.6 MHz (“X”), 0.6 MHz (“Y”) switching frequency ■ ...
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White LED Flash Application 2 20059153 20059156 20059155 ...
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... Connection Diagram Ordering Information Order Number Package Type LM2731XMF LM2731XMFX SOT23-5 LM2731YMF LM2731YMFX Pin Descriptions Pin Name 1 SW Drain of the internal FET switch. 2 GND Analog and power ground Feedback point that connects to external resistive divider. 4 SHDN Shutdown control input. Connect to Vin if the feature is not used. ...
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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. Storage Temperature Range Operating Junction Temperature Range Lead Temp. (Soldering, 5 sec.) Electrical Characteristics Limits in standard typeface are for T ≤ ≤ (−40°C T +125° ...
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Symbol Parameter D Maximum Duty Cycle MAX (Note 7) I Switch Leakage L Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the component may occur. Electrical specifications do not apply when operating the device outside of the ...
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Oscillator Frequency vs Temperature - "X" Max. Duty Cycle vs Temperature - "X" Iq Vin (Idle) vs Temperature www.national.com Oscillator Frequency vs Temperature - "Y" 20059105 Max. Duty Cycle vs Temperature - "Y" 20059107 Feedback Bias Current vs Temperature 20059125 ...
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Feedback Voltage vs Temperature 20059127 Current Limit vs Temperature 20059129 Efficiency vs Load Current - "X" 2.7V OUT 20059135 R (ON) vs Temperature DS R (ON Efficiency vs Load Current ...
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Efficiency vs Load Current - "X" 4.2V OUT Efficiency vs Load Current - "X" 3.3V OUT Efficiency vs Load Current - "X" 5V OUT www.national.com = 5V 20059137 ...
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Efficiency vs Load Current - "Y" 3.3V OUT 20059143 Efficiency vs Load Current - "Y" 2.7V 12V IN OUT 20059145 Efficiency vs Load Current - "Y" 5V, V ...
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Block Diagram Theory of Operation The LM2731 is a switching converter IC that operates at a fixed frequency (0.6 or 1.6 MHz) for fast transient response over a wide input voltage range and incorporates pulse-by- pulse current limiting protection. Because ...
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EMI passed back along that line to other circuitry. FEED-FORWARD COMPENSATION Although internally compensated, the feed-forward capacitor Cf is required for stability ...
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DUTY CYCLE The maximum duty cycle of the switching regulator deter- mines the maximum boost ratio of output-to-input voltage that the converter can attain in continuous mode of operation. The duty cycle for a given boost application is defined as: ...
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Switch Current Limit vs Duty Cycle - "X" Switch Current Limit vs Duty Cycle - "Y" CALCULATING LOAD CURRENT As shown in the figure which depicts inductor current, the load current is related to the average inductor current by the ...
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There will be some switching losses as well, so some derating needs to be applied when calculating IC power dissipation. INDUCTOR SUPPLIERS Recommended suppliers of inductors for this product include, but are not limited to Sumida, Coilcraft, Panasonic, TDK and ...
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... Physical Dimensions inches (millimeters) unless otherwise noted Order Number LM2731XMF, LM2731XMFX, LM2731YMF or LM2731YMFX 5-Lead SOT-23 Package NS Package Number MF05A 15 www.national.com ...
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