LM2672N-ADJ National Semiconductor, LM2672N-ADJ Datasheet
LM2672N-ADJ
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LM2672N-ADJ Summary of contents
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... Typical Application (Fixed Output Voltage Versions) SIMPLE SWITCHER ® registered trademark of National Semiconductor Corporation. Windows ® registered trademark of Microsoft Corporation. © 2005 National Semiconductor Corporation Power Converter High Efficiency ® To simplify the LM2672 buck regulator design procedure, there exists computer design software, LM267X Made Simple version 6 ...
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... LM2672M-ADJ 2672M-ADJ LM2672MX-ADJ 2672M-ADJ LM2672N-12 LM2672N-12 LM2672N-3.3 LM2672N-3.3 LM2672N-5.0 LM2672N-5.0 LM2672N-ADJ LM2672N-ADJ 2 8-Lead Package Top View 01293402 SO-8/DIP Package Supplied as: 1000 Units on Tape and Reel 4500 Units on Tape and Reel 1000 Units on Tape and Reel 4500 Units on Tape and Reel 1000 Units on Tape and Reel ...
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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. Supply Voltage ON/OFF Pin Voltage Switch Voltage to Ground Boost Pin Voltage Feedback Pin Voltage ESD Susceptibility Human Body Model (Note 2) Power Dissipation ...
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LM2672-ADJ (Continued) Symbol Parameter η Efficiency V = 12V All Output Voltage Versions Specifications with standard type face are for T Range. Unless otherwise specified, V and I = 100 mA. LOAD Symbol Parameters DEVICE PARAMETERS I Quiescent ...
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Typical Performance Characteristics Normalized Output Voltage Efficiency Switch Current Limit 01293403 01293405 01293407 5 Line Regulation 01293404 Drain-to-Source Resistance 01293406 Operating Quiescent Current 01293408 www.national.com ...
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Typical Performance Characteristics Standby Quiescent Current ON/OFF Pin Current (Sourcing) Feedback Pin Bias Current www.national.com (Continued) 01293409 01293411 01293413 6 ON/OFF Threshold Voltage 01293410 Switching Frequency 01293412 Peak Switch Current 01293414 ...
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Typical Performance Characteristics Dropout Voltage — 3.3V Option Block Diagram * Patent Number 5,514,947 † Patent Number 5,382,918 (Continued) Dropout Voltage — 5.0V Option 01293415 FIGURE 1. 7 01293416 01293417 www.national.com ...
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Typical Performance Characteristics (Circuit of Figure 2) Continuous Mode Switching Waveforms V = 20V 5V OUT µ µF, C OUT A: V Pin Voltage, 10 V/div Inductor Current, ...
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Test Circuit and Layout Guidelines µF, 50V Tantalum, Sprague “199D Series” µF, 25V Tantalum, Sprague “595D Series” OUT D1 - 3.3A, 50V Schottky Rectifier, IR 30WQ05F µH Sumida # RCR110D-680L ...
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LM2672 Series Buck Regulator Design Procedure (Fixed Output) PROCEDURE (Fixed Output Voltage Version) To simplify the buck regulator design procedure, National Semiconductor is making available computer design software to be used with the SIMPLE SWITCHER line of switching regulators. LM267X ...
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LM2672 Series Buck Regulator Design Procedure (Fixed Output) PROCEDURE (Fixed Output Voltage Version) The capacitor list contains through-hole electrolytic capacitors from four different capacitor manufacturers and surface mount tantalum capacitors from two different capacitor manufacturers recommended that both ...
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LM2672 Series Buck Regulator Design Procedure (Fixed Output) PROCEDURE (Fixed Output Voltage Version) 4. Input Capacitor ( low ESR aluminum or tantalum bypass capacitor is needed between the input pin and ground to prevent large voltage transients ...
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LM2672 Series Buck Regulator Design Procedure (Fixed Output) PROCEDURE (Fixed Output Voltage Version) 7. Frequency Synchronization (optional) The LM2672 (oscillator) can be synchronized to run with an external oscillator, using the sync pin (pin 3). By doing so, the LM2672 ...
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Ind. Inductance Current Ref. Through (µH) (A) Desg. Hole L4 68 0.32 67143940 67144310 L5 47 0.37 67148310 67148420 L6 33 0.44 67148320 67148430 L7 22 0.52 67148330 67148440 L9 220 0.32 67143960 67144330 L10 150 0.39 67143970 67144340 L11 ...
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Surface Mount Output Inductance Voltage Sprague (µH) (V) 594D Series (µF/V) 22 120/6.3 33 120/6.3 47 68/10 3.3 68 120/6.3 100 120/6.3 150 120/6.3 22 100/16 33 68/10 47 68/10 5.0 68 100/16 100 100/16 150 100/16 22 120/20 33 ...
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International Rectifier Corp. Motorola, Inc. General Instruments Corp. Diodes, Inc. FIGURE 14. RMS Current Ratings for Low ESR Electrolytic Capacitors (Typical) www.national.com 1A Diodes 3A Diodes V Surface Through Surface R Mount Hole Mount SK12 1N5817 ...
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FIGURE 15. Recommended Application Voltage for AVX TPS and Sprague 594D Tantalum Chip Capacitors Derated for 85˚C. LM2672 Series Buck Regulator Design Procedure (Adjustable Output) PROCEDURE (Adjustable Output Voltage Version) To simplify the buck regulator design procedure, National Semiconductor is ...
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LM2672 Series Buck Regulator Design Procedure (Adjustable Output) (Continued) PROCEDURE (Adjustable Output Voltage Version) 2. Inductor Selection (L1) A. Calculate the inductor Volt • microsecond constant E • • µs), from the following formula: where V =internal switch ...
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LM2672 Series Buck Regulator Design Procedure (Adjustable Output) (Continued) PROCEDURE (Adjustable Output Voltage Version) 4. Catch Diode Selection (D1 normal operation, the average current of the catch diode is the load current times the catch diode duty cycle, ...
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LM2672 Series Buck Regulator Design Procedure (Adjustable Output) (Continued) Case Output Style (Note 7) Voltage (V) SM and TH 1.21–2.50 SM and TH 2.50–3.75 SM and TH 3.75–5.0 SM and TH 5.0–6.25 SM and TH 6.25–7.5 SM and TH 7.5–10.0 ...
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LM2672 Series Buck Regulator Design Procedure (Adjustable Output) (Continued) Surface Mount Cap. Sprague AVX TPS Ref. Desg. 594D Series Series # (µF/V) (µF/V) C1 120/6.3 100/10 C2 120/6.3 100/10 C3 120/6.3 100/10 C4 68/10 100/10 C5 100/16 100/10 C6 100/16 ...
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Application Information TYPICAL SURFACE MOUNT PC BOARD LAYOUT, FIXD OUTPUT (4X SIZE µF, 50V, Solid Tantalum Sprague, “594D series” µF, 16V, Solid Tantalum Sprague, “594D series” OUT D1 - 1A, 40V Schottky Rectifier, ...
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Application Information LLP PACKAGE DEVICES The LM2672 is offered in the 16 lead LLP surface mount package to allow for increased power dissipation compared to the SO-8 and DIP. The Die Attach Pad (DAP) can and should be connected to ...
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Physical Dimensions unless otherwise noted 8-Lead (0.150" Wide) Molded Small Outline Package, JEDEC www.national.com inches (millimeters) Order Number LM2672M-3.3, LM2672M-5.0, LM2672M-12 or LM2672M-ADJ NS Package Number M08A 24 ...
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... Physical Dimensions inches (millimeters) unless otherwise noted (Continued) 8-Lead (0.300" Wide) Molded Dual-In-Line Package Order Number LM2672N-3.3, LM2672N-5.0, LM2672N-12 or LM2672N-ADJ NS Package Number N08E 25 www.national.com ...
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... BANNED SUBSTANCE COMPLIANCE National Semiconductor manufactures products and uses packing materials that meet the provisions of the Customer Products Stewardship Specification (CSP-9-111C2) and the Banned Substances and Materials of Interest Specification (CSP-9-111S2) and contain no ‘‘Banned Substances’’ as defined in CSP-9-111S2. ...