LM2673LD-12 National Semiconductor, LM2673LD-12 Datasheet
LM2673LD-12
Specifications of LM2673LD-12
Related parts for LM2673LD-12
LM2673LD-12 Summary of contents
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... The clock frequency is ± controlled to within a 11% tolerance. Typical Application SIMPLE SWITCHER ® registered trademark of National Semiconductor Corporation. © 2003 National Semiconductor Corporation 3A Step-Down Voltage Regulator ® Features n Efficiency up to 94% n Simple and easy to design with (using off-the-shelf external components) n Resistor programmable peak current limit over a range ...
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... Connection Diagrams and Ordering Information TO-263 Package Top View Order Number LM2673S-3.3, LM2673S-5.0, LM2673S-12 or LM2673S-ADJ See NSC Package Number TS7B Ordering Information for LLP Package Output Voltage Order Information 12 LM2673LD-12 12 LM2673LDX-12 3.3 LM2673LD-3.3 3.3 LM2673LDX-3.3 5.0 LM2673LD-5.0 5.0 LM2673LDX-5.0 ADJ LM2673LD-ADJ ...
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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. Input Supply Voltage Softstart Pin Voltage Switch Voltage to Ground Boost Pin Voltage Feedback Pin Voltage Power Dissipation ESD (Note 2) Electrical Characteristics range of operation, − ...
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All Output Voltage Versions Electrical Characteristics Limits appearing in bold type face apply over the entire junction temperature range of operation, −40˚C to 125˚C. Specifica- tions appearing in normal type apply for T and Adjustable versions and V =24V for ...
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All Output Voltage Versions Electrical Characteristics Note 1: Absolute Maximum Ratings are limits beyond which damage to the device may occur. Operating Ratings indicate conditions under which of the device is guaranteed. Operating Ratings do not imply guaranteed performance limits. ...
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Typical Performance Characteristics Normalized Output Voltage Efficiency vs Input Voltage Switch Current Limit www.national.com 10091304 10091306 Operating Quiescent Current 10091308 6 Line Regulation 10091305 Efficiency vs I LOAD 10091307 10091309 ...
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Typical Performance Characteristics Switching Frequency Load Transient Response for Continuous Mode V = 20V OUT µ 200 µF, C OUT OUT A: Output Voltage, 100 mV//div, AC-Coupled. B: Load Current: 500 ...
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Block Diagram * Active Inductor Patent Number 5,514,947 † Active Capacitor Patent Number 5,382,918 www.national.com 8 10091314 ...
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Application Hints The LM2673 provides all of the active functions required for a step-down (buck) switching regulator. The internal power switch is a DMOS power MOSFET to provide power supply designs with high current capability 3A, and highly ...
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Application Hints (Continued) DESIGN CONSIDERATIONS FIGURE 1. Basic circuit for fixed output voltage applications. FIGURE 2. Basic circuit for adjustable output voltage applications Power supply design using the LM2673 is greatly simplified by using recommended external components. A wide range ...
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Application Hints (Continued) maximum ripple current of 30% of the maximum load cur- rent. If the ripple current exceeds this 30% limit the next larger value is selected. The inductors offered have been specifically manufactured to provide proper operation under ...
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Application Hints (Continued) (which could saturate with excessively high currents) and the catch diode be able to safely handle which would be conducted under load fault conditions application only requires a load current of 2A ...
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Application Hints (Continued) rms current rating greater than 1.25A (1/2 I using Table 2 for specific component characteristics the following choices are suitable 1000µF/63V Sanyo MV-GX (code C14 820µF/63V Nichicon PL (code C24 560µF/50V ...
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Application Hints (Continued) 30WQ04F MBRS340 MBRD340 Step 7: A 0.01µF capacitor will be used for Cboost. The softstart pin will be left open circuited. Step 8: Determine a value for R to provide a peak switch ADJ current limit of ...
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Inductor Selection Guides FIGURE 3. LM2673-3.3 FIGURE 5. LM2673-12 For Continuous Mode Operation 10091319 10091321 15 10091320 FIGURE 4. LM2673-5.0 10091322 FIGURE 6. LM2673-ADJ www.national.com ...
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Inductor Selection Guides Inductor Inductance Current Reference (µH) (A) Number L23 33 1.35 L24 22 1.65 L25 15 2.00 L29 100 1.41 L30 68 1.71 L31 47 2.06 L32 33 2.46 L33 22 3.02 L34 15 3.65 L38 68 2.97 ...
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Capacitor Selection Guides Capacitor AVX TPS Series Reference Code C (µF) WV (V) C1 330 C2 100 C3 220 100 C10 22 C11 C12 C13 Table 2. Input and ...
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Capacitor Selection Guides Table 2. Input and Output Capacitor Codes (continued) Capacitor Sanyo OS-CON SA Series Reference Code C (µ 6.3 C2 150 6.3 C3 330 6.3 C4 100 10 C5 220 ...
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Capacitor Selection Guides Table 3. Output Capacitors for Fixed Output Voltage Application Output Inductance Voltage (V) (µ 3 100 Output Inductance Sanyo OS-CON ...
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Capacitor Selection Guides Table 4. Input Capacitors for Fixed Output Voltage Application (Assumes worst case maximum input voltage and load current for a given inductance value) Output Inductance Voltage (V) (µ 3 ...
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Capacitor Selection Guides Reverse Voltage (V) 20V 30V 40V 50V or More International Rectifier Motorola General Semiconductor Diodes, Inc. (Continued) Table 5. Schottky Diode Selection Table Surface Mount More 3A SK32 1N5820 SR302 SK33 MBRD835L 1N5821 30WQ03F ...
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Capacitor Selection Guides Table 6. Output Capacitors for Adjustable Output Voltage Applications Output Voltage Inductance (V) (µH) 1.21 to 2.50 2.5 to 3.75 3. 6.25 6.25 to 7.5 7 12.5 12.5 to ...
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Capacitor Selection Guides Table 6. Output Capacitors for Adjustable Output Voltage Applications (continued) Output Voltage Inductance Sanyo OS-CON SA (V) (µH) No 1. 2 ...
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Physical Dimensions unless otherwise noted www.national.com inches (millimeters) TO-263 Surface Mount Power Package Order Number LM2673S-3.3, LM2673S-5.0, LM2673S-12 or LM2673S-ADJ NS Package Number TS7B 24 ...
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Physical Dimensions inches (millimeters) unless otherwise noted (Continued) TO-220 Power Package Order Number LM2673T-3.3, LM2673T-5.0, LM2673T-12 or LM2673T-ADJ NS Package Number TA07B 25 www.national.com ...
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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 ...