LM2679S-5.0 National Semiconductor, LM2679S-5.0 Datasheet
LM2679S-5.0
Specifications of LM2679S-5.0
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LM2679S-5.0 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. © 2005 National Semiconductor Corporation 5A Step-Down Voltage Regulator ® Features n Efficiency up to 92% 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 LM2679S-3.3, LM2679S-5.0, LM2679S-12 or LM2679S-ADJ See NSC Package Number TS7B Ordering Information for LLP Package Output Voltage Order Information 12 LM2679SD-12 12 LM2679SDX-12 3.3 LM2679SD-3.3 3.3 LM2679SDX-3.3 5.0 LM2679SD-5.0 5.0 LM2679SDX-5.0 ADJ LM2679SD-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 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 10084704 10084706 Operating Quiescent Current 10084708 6 Line Regulation 10084705 Efficiency vs I LOAD 10084707 10084709 ...
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Typical Performance Characteristics Switching Frequency Continuous Mode Switching Waveforms V = 20V 5V OUT LOAD µ 400 µF, C OUT OUT A: V Pin Voltage, 10 V/div Inductor Current, ...
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Block Diagram * Active Inductor Patent Number 5,514,947 † Active Capacitor Patent Number 5,382,918 www.national.com 8 10084714 ...
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Application Hints The LM2679 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 5A, 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 LM2679 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 3A ...
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... Step 1: Operating conditions are: Vout = 14.8V Vin max = 28V Iload max = 3.5A Step 2: Select an LM2679S-ADJ. To set the output voltage to 14.9V two resistors need to be chosen (R1 and R2 in Figure 2). For the adjustable device the output voltage is set by the following relationship: Where V is the feedback voltage of typically 1.21V. ...
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Application Hints (Continued) where V is the voltage drop across the internal power SAT switch which is R times this example this would ds(ON) load be typically 0.12Ω x 3.5A or 0.42V and V across the forward ...
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Inductor Selection Guides FIGURE 3. LM2679-3.3 FIGURE 5. LM2679-12 For Continuous Mode Operation 10084719 10084721 15 10084720 FIGURE 4. LM2679-5.0 10084722 FIGURE 6. LM2679-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 Capacitor Sanyo OS-CON SA Series Reference Code C (µ 6.3 C2 150 6.3 C3 330 6.3 C4 100 10 C5 220 100 16 C8 150 16 C9 100 ...
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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 Through Hole More 3A SK32 1N5820 SR302 SK33 MBRD835L ...
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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 Output Capacitors for Adjustable Output Voltage Applications (continued) Output Voltage Inductance Sanyo OS-CON SA (V) (µH) No. 33* 1.21 to 2.50 47* 33* 2.5 to 3.75 47 ...
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... Physical Dimensions unless otherwise noted www.national.com inches (millimeters) TO-263 Surface Mount Power Package Order Number LM2679S-3.3, LM2679S-5.0, LM2679S-12 or LM2679S-ADJ NS Package Number TS7B 24 ...
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Physical Dimensions inches (millimeters) unless otherwise noted (Continued) TO-220 Power Package Order Number LM2679T-3.3, LM2679T-5.0, LM2679T-12 or LM2679T-ADJ NS Package Number TA07B 14-Lead LLP Package NS Package Number SRC14A 25 www.national.com ...
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