lm2676sx-12 National Semiconductor Corporation, lm2676sx-12 Datasheet
lm2676sx-12
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lm2676sx-12 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. © 2005 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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Connection Diagrams and Ordering Information TO-263 Package Top View Order Number LM2676S-3.3, LM2676S-5.0, LM2676S-12 or LM2676S-ADJ See NSC Package Number TS7B Ordering Information for LLP Package Output Voltage Order Information 12 LM2676SD-12 12 LM2676SDX-12 3.3 LM2676SD-3.3 3.3 LM2676SDX-3.3 5.0 LM2676SD-5.0 ...
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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 ...
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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) ADDITIONAL APPLICATON INFORMATION When the output voltage is greater than approximately 6V, and the duty cycle at minimum input voltage is greater than approximately 50%, the designer should exercise caution in selection of the output filter components. ...
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Application Hints (Continued) Step 6: From Table Schottky diode must be selected. For through-hole components 20V rated diodes are sufficient and 2 part types are suitable: 1N5820 SR302 Step 7: A 0.01µF capacitor will be used for ...
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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 Input and Output Capacitor ...
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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) (µH) 33* 2.5 to 3.75 47 6.25 to ...
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Capacitor Selection Guides Output Capacitors for Adjustable Output Voltage Applications (continued) Output Voltage Inductance Sanyo OS-CON SA (V) (µH) 33* 1.21 to 2.50 47* 33* 2.5 to 3.75 47 6.25 ...
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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 14-Lead LLP Package NS Package Number SRC14A 24 ...
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National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications. For the most current product information ...