LM2676LD-ADJ National Semiconductor, LM2676LD-ADJ Datasheet
LM2676LD-ADJ
Specifications of LM2676LD-ADJ
Related parts for LM2676LD-ADJ
LM2676LD-ADJ Summary of contents
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... The output voltage is guaranteed to a ance. The clock frequency is controlled to within a tolerance. Typical Application SIMPLE SWITCHER ® registered trademark of National Semiconductor Corporation. © 2003 National Semiconductor Corporation High Efficiency 3A Step-Down ® Features n Efficiency up to 94% n Simple and easy to design with (using off-the-shelf external components) n 150 mΩ ...
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... Order Information 12 LM2676LD-12 12 LM2676LDX-12 3.3 LM2676LD-3.3 3.3 LM2676LDX-3.3 5.0 LM2676LD-5.0 5.0 LM2676LDX-5.0 ADJ LM2676LD-ADJ ADJ LM2676LDX-ADJ www.national.com 10091401 LM2676T-3.3, LM2676T-5.0, LM2676T-12 or LM2676T-ADJ See NSC Package Number TA07B Top View 10091441 LLP-14 See NS package Number LDC14A Package Marking S0000EB 250 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. Input Supply Voltage ON/OFF 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 versions and V =24V for the 12V ...
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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 10091409 10091411 Operating Quiescent Current 10091404 6 Line Regulation 10091410 Efficiency vs I LOAD 10091412 10091405 ...
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Typical Performance Characteristics Standby Quiescent Current ON/OFF Pin Current (Sourcing) Feedback Pin Bias Current (Continued) ON/OFF Threshold Voltage 10091440 10091414 10091416 7 10091413 Switching Frequency 10091415 www.national.com ...
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Typical Performance Characteristics Continuous Mode Switching Waveforms V = 20V 5V OUT µ 200 µF, C OUT A: V Pin Voltage, 10 V/div Inductor Current, 1 A/div C: Output ...
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Block Diagram * Active Inductor Patent Number 5,514,947 † Active Capacitor Patent Number 5,382,918 9 10091406 www.national.com ...
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Application Hints The LM2676 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 LM2676 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) SIMPLE DESIGN PROCEDURE Using the nomographs and tables in this data sheet (or use the available design software at http://www.national.com) a complete step-down regulator can be designed in a few simple steps. Step 1: Define the power ...
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Application Hints (Continued) be typically 0.15Ω 0.3V and V across the forward bisased Schottky diode, typically 0.5V. The switching frequency of 260KHz is the nominal value to use to estimate the ON time of the switch during ...
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Inductor Selection Guides ous Mode Operation FIGURE 3. LM2676-3.3 FIGURE 4. LM2676-5.0 For Continu- 10091421 10091422 15 10091423 FIGURE 5. LM2676-12 10091424 FIGURE 6. LM2676-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 Nichicon Panasonic AVX Sprague/Vishay Sanyo Kemet Table 3. Output Capacitors for Fixed Output Voltage Application Output Inductance Voltage (V) (µ 3 ...
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Capacitor Selection Guides Output Inductance Sanyo OS-CON SA Voltage (V) (µH) Series No 100 1 No. represents the number of identical capacitor types to be connected in ...
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Capacitor Selection Guides Output Inductance Sanyo OS-CON SA Voltage (V) (µH) No 100 * * Check voltage rating of capacitors to be greater than application input voltage. ...
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Capacitor Selection Guides Table 6. Output Capacitors for Adjustable Output Voltage Applications (Continued) Output Voltage Inductance (V) (µ 2 ...
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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) (µ 1. 2 ...
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Physical Dimensions inches (millimeters) unless otherwise noted TO-263 Surface Mount Power Package Order Number LM2676S-3.3, LM2676S-5.0, LM2676S-12 or LM2676S-ADJ NS Package Number TS7B 23 www.national.com ...
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Physical Dimensions www.national.com inches (millimeters) unless otherwise noted (Continued) TO-220 Power Package Order Number LM2676T-3.3, LM2676T-5.0, LM2676T-12 or LM2676T-ADJ NS Package Number TA07B 24 ...
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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 ...