LM2745MTC/NOPB National Semiconductor, LM2745MTC/NOPB Datasheet
LM2745MTC/NOPB
Specifications of LM2745MTC/NOPB
*LM2745MTC/NOPB
LM2745MTC
Related parts for LM2745MTC/NOPB
LM2745MTC/NOPB Summary of contents
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... In addition, the shutdown pin of the IC can be used for providing startup delay, and the soft-start pin can be used for implementing precise tracking, for the purpose of sequencing with respect to an external rail. Typical Application © 2009 National Semiconductor Corporation Features ■ Switching frequency from 50 kHz to 1 MHz ■ ...
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Connection Diagrams 14-Lead Plastic TSSOP θ = 155°C Package Number MTC14 Ordering Information Order Number Package Type LM2745MTC LM2745MTCX TSSOP-14 LM2748MTC LM2748MTCX Pin Descriptions BOOT (Pin 1) - Bootstrap pin. This is the supply rail for the high-side ...
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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 BOOT Voltage I SEN FREQ/SYNC Voltage All other pins Junction Temperature Storage Temperature Soldering Information Electrical Characteristics V = 3.3V unless otherwise indicated. Typicals and limits appearing in plain type apply for T CC boldface type apply over full Operating Temperature Range ...
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Symbol Parameter GATE DRIVE I BOOT Pin Quiescent Current Q-BOOT R High-Side MOSFET Driver Pull-Up HG_UP ON resistance R High-Side MOSFET Driver Pull- HG_DN Down ON resistance R Low-Side MOSFET Driver Pull-Up LG_UP ON resistance R Low-Side MOSFET Driver Pull- ...
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Typical Performance Characteristics Efficiency (V = 1.2V) OUT V = 3.3V MHz CC SW Frequency vs Temperature Switch Waveforms V = 3.3V 5V OUT nF, f ...
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Start-Up (No-Load 3. Load Transient Response V = 3.3V 14V MHz SW Frequency vs. Frequency Adjust Resistor ...
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Maximum Duty Cycle 600 kHz SW 20137493 Maximum Duty Cycle MHz 20137494 www.national.com ...
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Block Diagram Application Information The LM2745 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- ers. ...
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ADJUST RESISTOR in the Typical Performance Character- istics section. When it is desired to synchronize the switching frequency with an external clock source, the LM2745 has the unique ability to synchronize from this external source within the range of 250 ...
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One way to use the tracking feature is to design the tracking resistor divider so that the master supply’s output voltage (V ) and the LM2745/8’s output voltage (represented sym- OUT1 bolically in Figure i.e. without ...
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For example, if the master supply output voltage slew rate was 1V/ms and the desired delay time between the startup of the master supply and LM2745/8 output voltage was 5 ms, then the desired SD pin slew rate would be ...
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So far, in the discussion above, the forward drop across the bootstrap diode has been ignored. But since that does affect the output of the driver somewhat good idea to include this drop in the following examples. ...
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POWER GOOD SIGNAL The open drain output on the Power Good pin needs a pull- up resistor to a low voltage source. The pull-up resistor should be chosen so that the current going into the Power Good pin is less ...
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SHUTDOWN If the shutdown pin is pulled low, (below 0.8V) the LM2745/8 enters shutdown mode, and discharges the soft-start capac- itor through a MOSFET switch. The high ...
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In this example, in order to maintain a 2% peak-to-peak output voltage ripple and a 40% peak-to-peak inductor current ripple, the required maximum ESR is 20 mΩ. The Sanyo 4SP560M electrolytic capacitor will give an equivalent ESR of 14 mΩ. ...
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FIGURE 13. Power Stage and Error Amp One popular method for selecting the compensation compo- nents is to create Bode plots of gain and phase for the power stage and error amplifier. Combined, they make the overall bandwidth and phase ...
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In most voltage mode compensation schemes, including Type III, a single pole is placed at the origin to boost DC gain as high as possible. Two zeroes f and f Z1 double pole frequency to cancel the double pole phase ...
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In practice, a good trade off between phase margin and band- width can be obtained by selecting the closest ±10% capac- itor values above what are suggested for C closest ±10% capacitor value below the suggestion for C and the ...
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The FDS6898A has a typical turn-on rise time t fall time and 16 ns, respectively. The switching f losses for this type of dual N-Channel MOSFETs are 0.061W. FET Conduction Loss (P ) CND P = ...
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Example Circuits PART PART NUMBER U1 LM2745 Q1 FDS6898A D1 MBR0520LTI L1 DO3316P-472 C 1 16SP100M 6SP220M VJ1206Y104KXXA CC BOOT VJ0805Y332KXXA C3 C VJ0805A123KXAA SS C ...
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PART PART NUMBER U1 LM2745 Q1 FDS6898A D1 MBR0520LTI L1 DO3316P-682 C 1 16SP100M 10SP56M VJ1206Y104KXXA CC BOOT VJ0805Y182KXXA C3 C VJ0805A123KXAA SS C VJ0805A821KXAA C2 ...
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PART PART NUMBER U1 LM2745 Q1 FDS6898A D1 MBR0520LTI L1 DO3316P-332 C 1 16SP100M 6SP220M VJ1206Y104KXXA CC BOOT VJ0805Y222KXXA C3 C VJ0805A123KXAA SS C VJ0805Y332KXXA C2 ...
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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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