LM2670LD-ADJ National Semiconductor, LM2670LD-ADJ Datasheet
LM2670LD-ADJ
Specifications of LM2670LD-ADJ
Related parts for LM2670LD-ADJ
LM2670LD-ADJ Summary of contents
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... The output voltage is guaranteed to a ance. 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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... Output Voltage Order Information 12 LM2670LD-12 12 LM2670LDX-12 3.3 LM2670LD-3.3 3.3 LM2670LDX-3.3 5.0 LM2670LD-5.0 5.0 LM2670LDX-5.0 ADJ LM2670LD-ADJ ADJ LM2670LDX-ADJ www.national.com 10094201 LM2670T-12 or LM2670T-ADJ See NSC Package Number TA07B Top View LLP-14 See NS package Number LDC14A Package Marking S00006B S00006B S00004B S00004B S00005B ...
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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 10094209 10094211 Operating Quiescent Current 10094204 6 Line Regulation 10094210 Efficiency vs I LOAD 10094212 10094205 ...
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Typical Performance Characteristics Standby Quiescent Current ON/OFF Pin Current (Sourcing) Feedback Pin Bias Current (Continued) ON/OFF Threshold Voltage 10094240 10094214 10094216 7 10094213 Switching Frequency 10094215 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 10094206 www.national.com ...
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Application Hints The LM2670 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 LM2670 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) pin 5. This RC network creates a short 100nS pulse on each positive edge of the clock to reset the internal ramp oscilla- tor. The reset time of the oscillator is approximately 300nS. SIMPLE DESIGN PROCEDURE Using ...
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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 0.15Ω 0.3V and V across the forward ...
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Inductor Selection Guides FIGURE 3. LM2670-3.3 FIGURE 5. LM2670-12 For Continuous Mode Operation 10094221 10094223 15 10094222 FIGURE 4. LM2670-5.0 10094224 FIGURE 6. LM2670-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 LM2670S-3.3, LM2670S-5.0, LM2670S-12 or LM2670S-ADJ NS Package Number TS7B 24 ...
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Physical Dimensions inches (millimeters) unless otherwise noted (Continued) TO-220 Power Package Order Number LM2670T-3.3, LM2670T-5.0, LM2670T-12 or LM2670T-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 ...