LM2733 National Semiconductor, LM2733 Datasheet
LM2733
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LM2733 Summary of contents
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... LM2733 0.6/1.6 MHz Boost Converters With 40V Internal FET Switch in SOT-23 General Description The LM2733 switching regulators are current-mode boost converters operating fixed frequency of 1.6 MHz (“X” option) and 600 kHz (“Y” option). The use of SOT-23 package, made possible by the minimal ...
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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 protection. Because this is current mode control mΩ sense resistor ...
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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 in standard typeface are for T J ≤ ...
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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 converters. ...
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... E =L/2 X (lp) 2 Where “lp” is the peak inductor current. An important point to observe is that the LM2733 will limit its switch current based on peak current. This means that since lp(max) is fixed, in- creasing L will increase the maximum amount of power avail- able to the load. Conversely, using too little inductance may limit the amount of load current which can be drawn from the output ...
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... FET and diode. For actual load current in typical applications, we took bench data for various input and output voltages for both the "X" and "Y" versions of the LM2733 and www.national.com displayed the maximum load current available for a typical ...
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... The minimum inductance should be selected such that the inductor (switch) current peak on each cycle does not reach the 1A current limit maximum. To understand how to do this, an example will be presented. In the example, the LM2733X will be used (nominal switching frequency 1.6 MHz, minimum switching 1 ...
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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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