lm2737mtcx National Semiconductor Corporation, lm2737mtcx Datasheet
lm2737mtcx
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lm2737mtcx Summary of contents
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... The high-side power FET drain voltage can be from 2.2V to 16V and the output voltage is adjustable down to 0.6V. Typical Application © 2003 National Semiconductor Corporation Features n Input power from 2.2V to 16V n Output voltage adjustable down to 0.6V n Power Good flag, adjustable soft-start and output enable ...
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Connection Diagram Pin Description BOOT (Pin 1) - Supply rail for the N-channel MOSFET gate drive. The voltage should be at least one gate threshold above the regulator input voltage to properly turn on the high-side N-FET. LG (Pin 2) ...
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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 BOOTV Junction Temperature Storage Temperature Soldering Information Lead Temperature (soldering, 10sec) Electrical Characteristics unless ...
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Electrical Characteristics unless otherwise indicated. Typicals and limits appearing in plain type apply for T CC boldface type apply over full Operating Temperature Range. Datasheet min/max specification limits are guaranteed by design, test, or statistical analysis. Symbol ...
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Typical Performance Characteristics Efficiency (V = 1.5V 300kHz 25˚ Operating Current vs Temperature 600kHz, No-Load SW Bootpin Current vs Temperature with 5V Bootstrap F = 600kHz, Si4826DY FET, No-Load ...
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Typical Performance Characteristics R vs PWM Frequency FADJ (in 100 to 800kHz range Operating Current Plus Boot Current vs CC PWM Frequency (Si4826DY FET, T Switch Waveforms (HG Rising 5V 1. ...
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Typical Performance Characteristics Start-Up (Full-Load 10V 1. 10A 10nF 300kHz SW Start Up (Full Load, 10x 10V 1. ...
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Typical Performance Characteristics Load Transient Response ( 12V 1. 300kHz SW Line Transient Response ( 1.2V 300kHz SW www.national.com (Continued ...
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Block Diagram Application Information THEORY OF OPERATION The LM2727 is a voltage-mode, high-speed synchronous buck regulator with a PWM control scheme designed for use in set-top boxes, thin clients, DSL/Cable modems, and other applications that require high efficiency ...
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Application Information MOSFET GATE DRIVERS The LM2727/37 has two gate drivers designed for driving N-channel MOSFETs in a synchronous mode. Power for the drivers is supplied through the BOOTV pin. For the high side gate (HG) to fully turn on ...
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Application Information DESIGN CONSIDERATIONS The following is a design procedure for all the components needed to create the circuit shown in Figure 3 in the Ex- ample Circuits section 1.2V out converter, capable of delivering 10A ...
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Application Information In this example, in order to maintain a 2% peak-to-peak output voltage ripple and a 40% peak-to-peak inductor cur- rent ripple, the required maximum ESR is 6mΩ. Three Sanyo 10MV5600AX capacitors in parallel will give an equivalent ESR ...
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Application Information FET Conduction Loss P = 0.533W Cn Input Capacitor Loss 2 4.28 *0.018/2 = 0.084W Example Circuits This circuit and the one featured on the front page have been designed to deliver high current and high efficiency in ...
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Example Circuits (Continued) This circuit design, detailed in the Design Considerations section, uses inexpensive aluminum capacitors and off-the- shelf inductors. It can deliver 10A at better than 85% effi- ciency. Large bulk capacitance on input and output ensure stable operation. ...
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Example Circuits (Continued) The circuit of Figure 5 demonstrates the LM2727 delivering a low output voltage at high efficiency (87%) A separate 5V supply is required to run the chip, however the input voltage can be as low as 2.2 ...
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Example Circuits (Continued) FIGURE 6. 1.8V and 3.3V, 1A, 1.4MHz, Simultaneous The circuits in Figure 6 are intended for ADSL applications, where the high switching frequency keeps noise out of the data transmission range. In this design, the 1.8 and ...
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Example Circuits (Continued) FIGURE 7. 12V Unregulated to 3.3V, 3A, 750kHz This circuit shows the LM27x7 paired with a cost effective solution to provide the 5V chip power supply, using no extra components other than the LM78L05 regulator itself. The ...
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TABLE 1. Bill of Materials for Typical Application Circuit ID Part Number U1 LM2727 Q1, Q2 Si4884DY L1 RLF7030T-1R5N6R1 Cin1, Cin2 C2012X5R1J106M Cinx C3216X7R1E105K Co1, Co2 6MV2200WG Cboot VJ1206X104XXA Cin C3216X7R1E225K Css VJ1206X123KXX Cc1 VJ1206A2R2KXX Cc2 VJ1206A181KXX Rin CRCW1206100J Rfadj ...
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TABLE 3. Bill of Materials for Circuit of Figure 3 (Continued) ID Part Number Cc1 VJ1206A4R7KXX Cc2 VJ1206A102KXX Rin CRCW1206100J Rfadj CRCW12068872F Rc1 CRCW12062293F Rfb1 CRCW12064991F Rfb2 CRCW12064991F Rcs CRCW1206152J TABLE 4. Bill of Materials for Circuit of Figure 4 ...
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TABLE 5. Bill of Materials for Circuit of Figure 5 (Continued) ID Part Number Cc1 VJ1206A4R7KXX Cc2 VJ1206A681KXX Rin CRCW1206100J Rfadj CRCW12064992F Rc1 CRCW12061473F Rfb1 CRCW12061492F Rfb2 CRCW12064991F Rcs CRCW1206332J ID Part Number U1 LM2727 Q1/Q2 Si4826DY D1 BAT-54 Lin ...
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TABLE 8. Bill of Materials for Circuit of Figure 7 (Continued) ID Part Number U2 LM78L05 Q1/Q2 Si4826DY D1 BAT-54 Lin RLF7030T-1R0N64 L1 SLF12565T-4R2N5R5 Cin1 16MV680WG Cinx C3216X5R1C106M Co1 Co2 16MV680WG Cox C3216X5R10J06M Cboot VJ1206X104XXA Cin C3216X7R1E225K Css VJ1206X123KXX Cc1 ...
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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 ...