LM2598S-ADJ National Semiconductor, LM2598S-ADJ Datasheet
LM2598S-ADJ
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LM2598S-ADJ Summary of contents
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... Patent Number 5,382,918. SIMPLE SWITCHER ® and Switchers Made Simple ® are registered trademarks of National Semiconductor Corporation. © 1999 National Semiconductor Corporation DS012593 Power Converter 150 kHz ® ternal shutdown is included, featuring typically 85 µA standby current. Self protection features include a two stage current limit for the output switch and an over temperature shutdown for complete protection under fault conditions ...
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... Connection Diagrams and Order Information Bent and Staggered Leads, Through Hole Package 7-Lead TO-220 (T) Order Number LM2598T-3.3, LM2598T-5.0, LM2598T-12 or LM2598T-ADJ See NS Package Number TA07B www.national.com Surface Mount Package 7-Lead TO-263 (S) DS012593-50 Order Number LM2598S-3.3, LM2598S-5.0, LM2598S-12 or LM2598S-ADJ See NS Package Number TS7B 2 DS012593-22 ...
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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 ( SD/SS Pin Input Voltage (Note 2) Delay Pin Voltage (Note 2) Flag Pin Voltage Feedback Pin Voltage Output Voltage to Ground ...
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LM2598-ADJ Electrical Characteristics Specifications with standard type face are for T ture Range. Symbol Parameter SYSTEM PARAMETERS (Note 6) Test Circuit Figure 1 V Feedback Voltage 4.5V FB programmed for 3V. Circuit of Figure OUT = 12V, ...
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... Note 14: Junction to ambient thermal resistance with the TO-263 package tab soldered to a single sided printed circuit board with 2.5 in Note 15: Junction to ambient thermal resistance with the TO-263 package tab soldered to a double sided printed circuit board with 3 in the LM2598S side of the board, and approximately Switchers Made Simple ® ...
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Typical Performance Characteristics Normalized Output Voltage DS012593-2 Switch Saturation Voltage DS012593-15 Operating Quiescent Current DS012593-4 Feedback Pin Bias Current DS012593-49 www.national.com (Circuit of Figure 1 ) Line Regulation DS012593-3 Switch Current Limit DS012593-16 Shutdown Quiescent Current DS012593-5 Flag Saturation Voltage ...
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Typical Performance Characteristics Soft-start DS012593-9 Soft-start Response DS012593-12 Typical Performance Characteristics Continuous Mode Switching Waveforms = 20V 5V OUT LOAD µ 120 µF, C ESR = 100 m ...
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Typical Performance Characteristics Load Transient Response for Continuous Mode = 20V 5V 250 mA to 750 OUT LOAD µ 120 µF, C ESR = 100 m OUT OUT ...
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Test Circuit and Layout Guidelines = 15V 5V, I Component Values shown are for V IN OUT 120 µF, 50V, Aluminum Electrolytic Nichicon “PL Series” 120 µF, 35V Aluminum Electrolytic, Nichicon “PL Series” 3A, 40V Schottky Rectifier, 1N5822 ...
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Test Circuit and Layout Guidelines (Continued any switching regulator, layout is very important. Rap- idly switching currents associated with wiring inductance can generate voltage transients which can cause problems. For minimal inductance and ground loops, the wires indicated ...
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LM2598 Series Buck Regulator Design Procedure (Fixed Output) PROCEDURE (Fixed Output Voltage Version simplify the capacitor selection procedure, refer to the quick design component selection table shown in Figure 2 . This table contains different input voltages, output ...
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LM2598 Series Buck Regulator Design Procedure (Fixed Output) PROCEDURE (Fixed Output Voltage Version) 4. Input Capacitor ( low ESR aluminum or tantalum bypass capacitor is needed between the input pin and ground to prevent large voltage transients ...
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LM2598 Series Buck Regulator Design Procedure (Adjustable Output) PROCEDURE (Adjustable Output Voltage Version) Given: = Regulated Output Voltage V OUT (max) = Maximum Input Voltage V IN (max) = Maximum Load Current I LOAD F = Switching Frequency (Fixed at ...
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LM2598 Series Buck Regulator Design Procedure (Adjustable Output) (Continued) PROCEDURE (Adjustable Output Voltage Version simplify the capacitor selection procedure, refer to the quick design table shown in Figure 3 . This table contains dif- ferent output voltages, and ...
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LM2598 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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LM2598 Series Buck Regulator Design Procedure INDUCTOR VALUE SELECTION GUIDES (For Continuous Mode Operation) FIGURE 4. LM2598-3.3 FIGURE 5. LM2598-5.0 www.national.com DS012593-25 FIGURE 6. LM2598-12 DS012593-26 FIGURE 7. LM2598-ADJ 16 DS012593-27 DS012593-28 ...
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LM2598 Series Buck Regulator Design Procedure Inductance Current Schott (µH) (A) Through Hole L4 68 0.32 67143940 L5 47 0.37 67148310 L6 33 0.44 67148320 L9 220 0.32 67143960 L10 150 0.39 67143970 L11 100 0.48 67143980 L12 68 0.58 ...
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LM2598 Series Buck Regulator Design Procedure Coilcraft Inc. Coilcraft Inc., Europe Pulse Engineering Inc. Pulse Engineering Inc., Europe Renco Electronics Inc. Schott Corp. FIGURE 9. Inductor Manufacturers Phone Numbers Nichicon Corp. Panasonic AVX Corp. Sprague/Vishay FIGURE 10. Capacitor Manufacturers Phone ...
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Block Diagram Application Information PIN FUNCTIONS +V (Pin 2) — This is the positive input supply for the IC IN switching regulator. A suitable input bypass capacitor must be present at this pin to minimize voltage transients and to supply ...
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Application Information the narrow pulses and ramp controlled manner. This is a very useful feature in some switcher topologies that re- quire large startup currents (such as the inverting configura- tion) which can load down the input ...
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Application Information (Continued) DELAY CAPACITOR C — Provides delay for the error flag output. See the DELAY upper curve in Figure 13 , and also refer to timing diagrams in Figure capacitor on this pin provides a ...
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Application Information A graph shown in Figure 15 shows the relationship between an electrolytic capacitor value, its voltage rating, and the RMS current it is rated for. These curves were obtained from the Nichicon “PL” series of low ESR, high ...
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Application Information (Continued) FIGURE 18 Peak-to-Peak Inductor IND 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 ...
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Application Information mended. (See Figure 1 .) The inductance required is typically between 1 µH and 5 µH, with low DC resistance, to maintain good load regulation. A low ESR output filter capacitor is also required to assure good dynamic ...
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Application Information (Continued) 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 ...
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... PC-board with large copper areas are recommended. The curves shown in Figure 22 show the LM2598S (TO-263 package) junction temperature rise above ambient tempera- ture with a 1A load for various input and output voltages. This ...
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Application Information (Continued) FIGURE 25. Typical Circuit Using Shutdown /Soft-start and Error Flag Features FIGURE 26. Inverting −5V Regulator With Shutdown and Soft-start lNVERTING REGULATOR The circuit in Figure 26 converts a positive input voltage to a negative output voltage ...
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Application Information FIGURE 27. Maximum Load Current for Inverting Regulator Circuit An additional diode is required in this regulator configuration. Diode D1 is used to isolate input voltage ripple or noise from coupling through the C capacitor to the output, ...
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Application Information (Continued) hundred mA on the regulated positive output for the charge pump to work correctly. Also, resistor R1 is required to limit the charging current some value less than the LM2598 current limit (typically 1.5A). ...
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Application Information TYPICAL THROUGH HOLE PC BOARD LAYOUT, FIXED OUTPUT (1X SIZE), DOUBLE SIDED, THROUGH HOLE C — 150 µF/50V Aluminum Electrolytic, Panasonic “HFQ series” — 120 µF/25V Aluminum Electrolytic, Panasonic “HFQ series” OUT D1 — 3A, 40V ...
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Application Information (Continued) TYPICAL THROUGH HOLE PC BOARD LAYOUT, ADJUSTABLE OUTPUT (1X SIZE), DOUBLE SIDED, C — 150 µF/50V, Aluminum Electrolytic, Panasonic “HFQ series” — 120 µF/25V Aluminum Electrolytic, Panasonic “HFQ series” OUT D1 — 3A, 40V Schottky ...
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Physical Dimensions inches (millimeters) unless otherwise noted www.national.com 7-Lead TO-220 (T) Order Number LM2598T-3.3, LM2598T-5.0, LM2598T-12 or LM2598T-ADJ NS Package Number TA07B 32 ...
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... Physical Dimensions inches (millimeters) unless otherwise noted (Continued) Order Number LM2598S-3.3, LM2598S-5.0, LM2598S-12 or LM2598S-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 ...