lm2733ymfx National Semiconductor Corporation, lm2733ymfx Datasheet

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... Protection is provided through cycle-by-cycle current limiting and thermal shutdown. Internal compensation simplifies de- sign and reduces component count. Switch Frequency X 1.6 MHz 0.6 MHz Typical Application Circuit © 2007 National Semiconductor Corporation Features ■ 40V DMOS FET switch ■ 1.6 MHz (“X”), 0.6 MHz (“Y”) switching frequency ■ Low R ■ ...

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Connection Diagram www.national.com 20055401 20055440 Top View 20055402 5-Lead SOT-23 Package See NS Package Number MF05A 2 20055458 20055459 ...

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... Ordering Information Order Package Package Supplied Number Type Drawing LM2733XMF LM2733XMFX SOT23-5 MF05A LM2733YMF LM2733YMFX 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 V ...

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Block Diagram Theory of Operation The LM2733 is a switching converter IC that operates at a fixed frequency (0.6 or 1.6 MHz) using current-mode control for fast transient response over a wide input voltage range and incorporate pulse-by-pulse current limiting ...

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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.) Power Dissipation (Note 2) Electrical Characteristics Limits ...

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Typical Performance Characteristics Iq V (Active) vs Temperature - "X" IN Oscillator Frequency vs Temperature - "X" Max. Duty Cycle vs Temperature - "X" www.national.com Unless otherwise specified (Active) vs Temperature - "Y" IN 20055410 Oscillator Frequency ...

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Feedback Voltage vs Temperature Current Limit vs Temperature Efficiency vs Load Current (V = 12V) - "X" OUT R (ON) vs Temperature DS 20055406 R 20055409 Efficiency vs Load Current (V 20055414 7 20055407 vs V DS(ON) IN 20055423 = ...

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Efficiency vs Load Current (V Efficiency vs Load Current (V Efficiency vs Load Current (V www.national.com = 20V) - "X" Efficiency vs Load Current (V OUT 20055446 = 30V) - "X" Efficiency vs Load Current (V OUT 20055448 = 40V) ...

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Efficiency vs Load (V = 20V) - "Y" OUT 20055427 Efficiency vs Load (V = 30V) - "Y" OUT 20055429 Efficiency vs Load (V = 40V) - "Y" OUT 20055432 Efficiency vs Load (V OUT Efficiency vs Load (V OUT ...

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Application Hints SELECTING THE EXTERNAL CAPACITORS The best capacitors for use with the LM2733 are multi-layer ceramic capacitors. They have the lowest ESR (equivalent series resistance) and highest resonance frequency which makes them optimum for use with high frequency switching ...

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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. MINIMUM INDUCTANCE In some applications where the maximum load current is rel- atively small, it may be advantageous to use ...

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... Physical Dimensions Order Number LM2733XMF, LM2733XMFX, LM2733YMF or LM2733YMFX www.national.com inches (millimeters) unless otherwise noted 5-Lead SOT-23 Package NS Package Number MF05A 14 ...

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Notes 15 www.national.com ...

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