LM2594N-12 National Semiconductor, LM2594N-12 Datasheet
LM2594N-12
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LM2594N-12 Summary of contents
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... Typical Application (Fixed Output Voltage Versions) SIMPLE SWITCHER and Switchers Made Simple ™ are registered trademarks of National Semiconductor Corporation. © 2000 National Semiconductor Corporation Power Converter 150 kHz 0.5A ® The LM2594HV is for applications requiring an input voltage up to 60V. ...
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... Connection Diagrams and Order Information 8-Lead DIP (N) DS012439-2 Top View Order Number LM2594N-3.3, LM2594N-5.0, LM2594N-12 or LM2594N-ADJ LM2594HVN-3.3, LM2594HVN-5.0, LM2594HVN-12 or LM2594HVN-ADJ See NS Package Number N08E *No internal connection, but should be soldered to pc board for best heat transfer. ‡ Patent Number 5,382,918. www.national.com 8-Lead Surface Mount (M) ...
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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. Maximum Supply Voltage LM2594 LM2594HV ON /OFF Pin Input Voltage Feedback Pin Voltage Output Voltage to Ground (Steady State) Power Dissipation Storage Temperature Range ESD Susceptibility LM2594/LM2594HV-3 ...
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LM2594/LM2594HV-ADJ Electrical Characteristics Specifications with standard type face are for T ture Range Symbol Parameter SYSTEM PARAMETERS (Note 5) Test Circuit Figure 1 V Feedback Voltage 4. OUT Efficiency V IN All Output Voltage Versions Electrical Characteristics Specifications ...
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All Output Voltage Versions Electrical Characteristics Note 2: The human body model is a 100 pF capacitor discharged through a 1.5k resistor into each pin. Note 3: Typical numbers are at 25˚C and represent the most likely norm. Note 4: ...
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Typical Performance Characteristics Quiescent Current DS012439-10 ON /OFF Threshold Voltage DS012439-13 Feedback Pin Bias Current DS012439-16 www.national.com (Continued) Standby Quiescent Current DS012439-11 ON /OFF Pin Current (Sinking) DS012439-14 6 Minimum Operating Supply Voltage DS012439-12 Switching Frequency DS012439-15 ...
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Typical Performance Characteristics Continuous Mode Switching Waveforms V = 20V 5V 400 mA IN OUT LOAD L = 100 µ 120 µF, C ESR = 140 m OUT OUT A: Output Pin Voltage, 10V/div. ...
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Typical Circuit and Layout Guidelines C — 68 µF, 35V, Aluminum Electrolytic Nichicon “PL Series” — 120 µF, 25V Aluminum Electrolytic, Nichicon “PL Series” OUT D1 — 1A, 40V Schottky Rectifier, 1N5819 L1 — 100 µH, L20 Select ...
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LM2594/LM2594HV Series Buck Regulator Design Procedure (Fixed Output) PROCEDURE (Fixed Output Voltage Version) Given Regulated Output Voltage (3.3V 12V) OUT V (max) = Maximum DC Input Voltage IN I (max) = Maximum Load Current LOAD 1. ...
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LM2594/LM2594HV Series Buck Regulator Design Procedure (Fixed Output) (Continued) PROCEDURE (Fixed Output Voltage Version) 3. Catch Diode Selection (D1) A. The catch diode current rating must be at least 1.3 times greater than the maximum load current. Also, if the ...
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LM2594/LM2594HV Series Buck Regulator Design Procedure (Fixed Output) (Continued) Conditions Output Load Max Input Voltage Current Voltage (V) (A) (V) 3 ...
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LM2594/LM2594HV Series Buck Regulator Design Procedure (Adjustable Output) (Continued) PROCEDURE (Adjustable Output Voltage Version) 1. Programming Output Voltage (Selecting R shown in Figure 1 . Use the following formula to select the appropriate resistor values. Select a value for R ...
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LM2594/LM2594HV Series Buck Regulator Design Procedure (Adjustable Output) (Continued) PROCEDURE (Adjustable Output Voltage Version) 4. Feedforward Capacitor (C ) (See Figure For output voltages greater than approximately 10V, an addi- tional capacitor is required. The compensation capacitor ...
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LM2594/LM2594HV Series Buck Regulator Design Procedure (Adjustable Output) (Continued) PROCEDURE (Adjustable Output Voltage Version) 6. Input Capacitor ( low ESR aluminum or tantalum bypass capacitor is needed between the input pin and ground to prevent large voltage ...
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LM2594/LM2594HV Series Buck Regulator Design Procedure INDUCTOR VALUE SELECTION GUIDES (For Continuous Mode Operation) FIGURE 4. LM2594/LM2594HV-3.3 FIGURE 6. LM2594/LM2594HV-12 DS012439-24 FIGURE 5. LM2594/LM2594HV-5.0 DS012439-26 FIGURE 7. LM2594/LM2594HV-ADJ 15 DS012439-25 DS012439-27 www.national.com ...
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LM2594/LM2594HV Series Buck Regulator Design Procedure Induc- Cur- tance rent Through (µH) (A) Hole L1 220 0.18 67143910 L2 150 0.21 67143920 L3 100 0.26 67143930 L4 68 0.32 67143940 L5 47 0.37 67148310 L6 33 0.44 67148320 L7 22 ...
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LM2594/LM2594HV Series Buck Regulator Design Procedure VR 1A Diodes Surface Mount Through Hole Ultra Fast Schot- Schottky tky Recovery 20V All of 1N5817 these diodes are SR102 MBRS130 rated to at 1N5818 30V least 60V. SR103 11DQ03 MBRS140 MURS120 1N5819 ...
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Application Information Feedback — Senses the regulated output voltage to com- plete the feedback loop. ON /OFF — Allows the switching regulator circuit to be shut down using logic level signals thus dropping the total input supply current to approximately ...
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Application Information (see Figure 14 ). Often, capacitors with much higher voltage ratings may be needed to provide the low ESR values re- quired for low output ripple voltage. The output capacitor for many different switcher designs of- ten can ...
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Application Information FIGURE 16 Peak-to-Peak IND Inductor Ripple Current (as a Percentage of the Load Current) vs Load Current By allowing the percentage of inductor ripple current to in- crease for low load currents, the inductor value ...
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Application Information reduction. The ESR of this capacitor may be as low as de- sired, because it is out of the regulator feedback loop. The photo shown in Figure 17 shows a typical output ripple volt- age, with and without ...
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Application Information These magnetic lines of flux will induce a voltage into any wire or PC board copper trace that comes within the induc- tor’s magnetic field. The strength of the magnetic field, the orientation and location of the PC ...
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Application Information The curves shown in Figure 19 and Figure 20 show the LM2594 junction temperature rise above ambient tempera- ture with a 500 mA load for various input and output volt- ages. This data was taken with the circuit ...
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Application Information This circuit has hysteresis Regulator starts switching 13V IN Regulator stops switching FIGURE 24. Undervoltage Lockout with Hysteresis for Inverting Regulator C — 68 µF/25V Tant. Sprague 595D IN 120 ...
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Application Information put reaches its nominal output voltage. The actual time de- pends on the output voltage and the size of the output capacitor. Input power sources that are current limited or sources that can not deliver these currents without ...
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Application Information TYPICAL SURFACE MOUNT PC BOARD LAYOUT, FIXED OUTPUT (2X SIZE) C — 10 µF, 35V, Solid Tantalum AVX, “TPS series” — 100 µF, 10V Solid Tantalum AVX, “TPS series” OUT D1 — 1A, 40V Schottky Rectifier, ...
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Physical Dimensions inches (millimeters) unless otherwise noted 8-Lead (0.150" Wide) Molded Small Outline Package, Order Number LM2594M-3.3, LM2594M-5.0, LM2594M-12 or LM2594M-ADJ JEDEC NS Package Number M08A 27 www.national.com ...
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... Physical Dimensions 8-Lead (0.300" Wide) Molded Dual-In-Line Package, Order Number LM2594N-3.3, LM2594N-5.0, LM2594N-12 or LM2594N-ADJ LIFE SUPPORT POLICY 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 ...