LM2578AM/NOPB National Semiconductor, LM2578AM/NOPB Datasheet
LM2578AM/NOPB
Specifications of LM2578AM/NOPB
*LM2578AM/NOPB
LM2578AM
Related parts for LM2578AM/NOPB
LM2578AM/NOPB Summary of contents
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... Connection Diagram and Ordering Information Order Number LM3578AM, LM2578AN or LM3578AN © 2005 National Semiconductor Corporation Features n Inverting and non-inverting feedback inputs n 1.0V reference at inputs n Operates from supply voltages 40V n Output current up to 750 mA, saturation less than 0 ...
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Functional Diagram www.national.com 00871101 2 ...
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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. Total Supply Voltage Collector Output to Ground Emitter Output to Ground (Note 2) Power Dissipation (Note 3) Output Current Storage Temperature Lead Temperature (soldering, 10 seconds) ...
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Electrical Characteristics These specifications apply for 2V ≤ V duty cycle ≤ 75%, unless otherwise specified. Values in standard typeface are for T operation over the specified operating junction temperature range. Symbol Parameter CURRENT LIMIT ∆V /∆T Sense Voltage Temperature ...
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Typical Performance Characteristics Input Reference Voltage Drift with Temperature Emitter Saturation Voltage (Sourcing Current, Collector Current Limit Sense Voltage Drift with Temperature (Continued) Collector Saturation Voltage 00871134 Current Limit Sense Voltage 00871136 Current Limit Response Time ...
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Typical Performance Characteristics Current Limit Sense Voltage vs Supply Voltage Supply Current Test Circuit* Parameter tests can be made using the test circuit shown. Select the desired V , collector voltage and duty cycle with in adjustable power supplies. A ...
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Test Circuit* (Continued) ± Op amp supplies are 15V > DVM input resistance 100 MΩ *LM2578 max duty cycle is 90% Definition of Terms Input Reference Voltage: The voltage (referred to ground) that must be applied to either the inverting ...
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Functional Description and R2. Thus, both inputs to the comparator will have the potential of the 1.0V reference example the non-inverting input, is pulled ∆V away from V a current of ∆V/R1 will flow through R1. This same ...
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Applications Information FIGURE 4. Current Limit Transient Suppressor, Ground Referred FIGURE 5. Current Limit Transient Suppressor, V Referred in C.L. SENSE VOLTAGE MULTIPLICATION When a larger sense resistor value is desired, the voltage divider network, consisting of R1 and R2, ...
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Applications Information FIGURE 9. Maximum Duty Cycle Limiting DUTY CYCLE ADJUSTMENT When manual or mechanical selection of the output transis- tor’s duty cycle is needed, the cirucit shown below may be used. The output will turn on with the beginning ...
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Applications Information 1.5V to 2.0V. The signal source must be capable of 1.) driving capacitive loads and 2.) delivering up to 500 µA for each LM2578A. Capacitors C1 thru CN are to be selected for a 20% slower frequency than ...
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Typical Applications www.national.com (Continued 15V R3 = 0.15Ω 1820 220 µF ripple I = 350 ...
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Typical Applications (Continued) FIGURE 16. DC/DC Inductance Calculator 13 00871131 www.national.com ...
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Typical Applications Step 1: Calculate the maximum DC current through the inductor The necessary equations are indicated at L(max) the top of the chart and show that I buck configuration. Thus 350 mA. L(max) Step 2: ...
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Typical Applications (Continued 15V R4 = 200Ω 330Ω 1820 pF ripple 330 µF o FIGURE 17. Buck Converter with Boosted ...
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Typical Applications Schottky type diode such as a 1N5818 or 1N5819 found as described in the buck converter section, using the inductance chart for Figure 16 for the boost configuration and 20% discontinuity. INVERTING REGULATOR ...
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Typical Applications (Continued) where: RS-232 LINE DRIVER POWER SUPPLY The power supply, shown in Figure 23, operates from an input voltage as low as 4.2V (5V nominal), and delivers an ± ± output of 12V with better ...
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Typical Applications A minimum value for an ideal output capacitor C3, could be calculated t/∆V where the transistor on time (typically 0.4/f osc to-peak output voltage ripple. A larger output capacitor than ...
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Physical Dimensions inches (millimeters) unless otherwise noted Plastic Surface-Mount Package (M) Order Number LM3578AM NS Package Number M08A 19 www.national.com ...
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