LM2742MTC National Semiconductor, LM2742MTC Datasheet
LM2742MTC
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LM2742MTC Summary of contents
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... MOSFET gate-drivers and high-side boot- strap structure helps to further maximize efficiency. The high- side power FET drain voltage can be from 1V to 16V and the output voltage is adjustable down to 0.6V. Typical Application © 2007 National Semiconductor Corporation Features ■ Input power from 1V to 16V ■ ...
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... Connection Diagram Ordering Information Order Number LM2742MTC LM2742MTCX Pin Descriptions 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) - Gate drive for the low-side N-channel MOSFET. ...
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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 LG and HG to GND (Note 3) Junction Temperature Storage Temperature Soldering Information Electrical Characteristics unless otherwise indicated. Typicals and limits appearing in plain type apply for T CC type apply over full Operating Temperature Range ...
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Symbol Parameter GATE DRIVE I BOOT Pin Quiescent Current Q-BOOT R Top FET Driver Pull-Up ON DS1 resistance R Top FET Driver Pull-Down ON DS2 resistance R Bottom FET Driver Pull-Up ON DS3 resistance R Bottom FET Driver Pull-Down ON ...
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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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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 3A 600kHz ...
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Start-Up (Full-Load 10V 1. 10A 10nF 300kHz SW 20087522 Start Up (Full Load, 10x 10V 1. ...
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Shutdown (No Load 12V 10A 300kHz SW Load Transient Response ( 12V 300kHz SW Line Transient Response ( 1.2V, ...
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Peak Current During Current Limit V = 12V 3.3V 4A LIM SW Block Diagram Peak Current During Current Limit = 300kHz µ 12V 20087552 9 = ...
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Application Information THEORY OF OPERATION The LM2742 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 buck convert- ...
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R can be found by using the following equa- CS tion (LOW DSON LIM For example, a conservative 15A current limit in a 10A design with a minimum R of 10mΩ would ...
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Each capacitor has a maximum ESR of 18mΩ at 100 kHz. Power loss in each device is then 0.05W, and total loss is 0.1W. Other possibilities for input and output capacitors include MLCC, tantalum, OSCON, SP, and POSCAPS. ...
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P the result is a loss of 0.533W. If this CND design were for 2.5V circuit, an equal number of FETs on the high and low sides would be the best solution. With the ...
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Example Circuits This circuit and the one featured on the front page have been designed to deliver high current and high efficiency in a small package, both in area and in height The tallest component in This circuit design, detailed ...
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The example circuit of Figure 5 has been designed for mini- mum component count and overall solution size. A switching frequency of 600kHz allows the use of small input/output ca- pacitors and a small inductor. The availability of separate 5V ...
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The circuits in Figure 7 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 3.3V out- puts come up simultaneously by using the same softstart ...
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FIGURE 8. 12V Unregulated to 3.3V, 3A, 750kHz This circuit shows the LM2742 paired with a cost effective solution to provide the 5V chip power supply, using no extra components other than the LM78L05 regulator itself. The in- put voltage ...
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TABLE 1. Bill of Materials for Typical Application Circuit ID Part Number U1 LM2742 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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ID Part Number Cc1 VJ1206A4R7KXX Cc2 VJ1206A102KXX Rin CRCW1206100J Rfadj CRCW12068872F Rc1 CRCW12062293F Rfb1 CRCW12064991F Rfb2 CRCW12064991F Rcs CRCW1206152J ID Part Number U1 LM2742 Q1/Q2 Si4826DY L1 DO3316P-222 Cin1 10TPB100ML Co1 4TPB220ML Cc C3216X7R1E105K Cin C3216X7R1E225K Css VJ1206X123KXX Cc1 VJ1206A100KXX ...
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ID Part Number Cc1 VJ1206A4R7KXX Cc2 VJ1206A681KXX Rin CRCW1206100J Rfadj CRCW12064992F Rc1 CRCW12061473F Rfb1 CRCW12061492F Rfb2 CRCW12064991F Rcs CRCW1206332J ID Part Number U1 LM2742 Q1/Q2 Si4826DY D1 BAT-54 Lin RLF7030T-1R0N64 L1 RLF7030T-3R3M4R1 Cin1 C4532X5R1E156M Co1 C4532X5R1E156M Cboot VJ1206X104XXA Cin C3216X7R1E225K ...
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ID Part Number U1 LM2742 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 VJ1206A8R2KXX Cc2 VJ1206X102KXX Cc3 VJ1206X472KXX Rfadj CRCW12063252F Rc1 CRCW12065232F ...
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ID Part Number Rfb2 CRCW12061002F Rcs CRCW1206122F www.national.com Type Size Resistor 1206 Resistor 1206 22 Parameters Qty. Vendor 10kΩ Vishay 1.2kΩ Vishay ...
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Physical Dimensions inches (millimeters) unless otherwise noted TSSOP-14 Pin Package NS Package Number MTC14 23 www.national.com ...
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