LM2577-12 NSC [National Semiconductor], LM2577-12 Datasheet
LM2577-12
Related parts for LM2577-12
LM2577-12 Summary of contents
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... LM1577/LM2577 Series SIMPLE SWITCHER General Description The LM1577/LM2577 are monolithic integrated circuits that provide all of the power and control functions for step-up (boost), flyback, and forward converter switching regulators. The device is available in three different output voltage ver- sions: 12V, 15V, and adjustable. ...
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... Output Switch Voltage Output Switch Current (Note 2) Power Dissipation Storage Temperature Range Lead Temperature (Soldering, 10 sec.) Maximum Junction Temperature Electrical Characteristics — LM1577-12, LM2577-12 Specifications with standard type face are for T Range. Unless otherwise specified Symbol Parameter SYSTEM PARAMETERS Circuit of Figure 1 (Note 6) ...
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... Electrical Characteristics — LM1577-12, LM2577-12 Specifications with standard type face are for T = 5V, and I Range. Unless otherwise specified Symbol Parameter DEVICE PARAMETERS Error Amplifier Upper Limit Output Swing V FEEDBACK Lower Limit V FEEDBACK Error Amplifier V FEEDBACK Output Current V COMP I Soft Start Current ...
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... Electrical Characteristics — LM1577-15, LM2577-15 Specifications with standard type face are for T Range. Unless otherwise specified Symbol Parameter DEVICE PARAMETERS Undervoltage Lockout f Oscillator Frequency O V Output Reference REF Voltage Output Reference Voltage Line Regulation R Feedback Pin Input FB Voltage Line Regulator ...
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... Electrical Characteristics — LM1577-ADJ, LM2577-ADJ Specifications with standard type face are for T = 5V, V Range. Unless otherwise specified Symbol Parameter SYSTEM PARAMETERS Circuit of Figure 3 (Note 6) V Output Voltage V OUT IN I LOAD (Note Line Regulation V OUT LOAD V / Load Regulation ...
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... For guaranteed specifications and test conditions, see the Electrical Characteristics. Note 2: Due to timing considerations of the LM1577/LM2577 current limit circuit, output current cannot be internally limited when the LM1577/LM2577 is used as a step-up regulator. To prevent damage to the switch, its current must be externally limited to 6.0A. However, output current is internally limited when the LM1577/ LM2577 is used as a flyback or forward converter regulator in accordance to the Application Hints ...
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Typical Performance Characteristics Reference Voltage vs Temperature DS011468-34 Reference Voltage vs Supply Voltage DS011468-37 Error Amp Transconductance vs Temperature DS011468-40 Reference Voltage vs Temperature DS011468-35 Reference Voltage vs Supply Voltage DS011468-38 Error Amp Transconductance vs Temperature DS011468-41 7 Reference Voltage ...
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Typical Performance Characteristics Error Amp Voltage Gain vs Temperature DS011468-43 Quiescent Current vs Temperature DS011468-46 Current Limit Response Time vs Overdrive DS011468-49 www.national.com (Continued) Error Amp Voltage Gain vs Temperature DS011468-44 Quiescent Current vs Switch Current DS011468-47 Switch Saturation Voltage ...
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... Top View Order Number LM2577T-12, LM2577T-15, or LM2577T-ADJ See NS Package Number T05A (Continued) Oscillator Frequency vs Temperature Bent, Staggered Leads 5-Lead TO-220 (T) DS011468-4 Top View Order Number LM2577T-12 Flow LB03, LM2577T-15 Flow LB03, or LM2577T-ADJ Flow LB03 See NS Package Number T05D 9 DS011468-53 DS011468-5 www.national.com ...
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... Side View Order Number LM2577S-12, LM2577S-15, or LM2577S-ADJ See NS Package Number TS5B www.national.com 24-Lead Surface Mount (M) DS011468 internal Connection Order Number LM2577M-12, LM2577M-15, or LM2577M-ADJ See NS Package Number M24B DS011468-32 Order Number LM1577K-12/883, LM1577K-15/883, See NS Package Number K04A 10 DS011468-7 Top View ...
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... LM1577-12, LM2577-12 Test Circuit L = 415-0930 (AIE any manufacturer = Sprague Type 673D C OUT Electrolytic 680 µF, 20V Note: Pin numbers shown are for TO-220 (T) package FIGURE 1. Circuit Used to Specify System Parameters for 12V Versions LM1577-15, LM2577-15 Test Circuit L = 415-0930 (AIE any manufacturer ...
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... Application Hints Note: Pin numbers shown are for TO-220 (T) package * Resistors are internal to LM1577/LM2577 for 12V and 15V versions. FIGURE 4. LM1577/LM2577 Block Diagram and Boost Regulator Application www.national.com DS011468-10 12 ...
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... Figure 4 shows the LM1577-ADJ/LM2577-ADJ used as a Step-Up Regulator. This is a switching regulator used for producing an output voltage greater than the input supply voltage. The LM1577-12/LM2577-12 and LM1577-15/ LM2577-15 can also be used for step-up regulators with 12V or 15V outputs (respectively), by tying the feedback pin di- rectly to the regulator output ...
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... Find the lowest value inductor that is greater than L 2. Find where E • T intersects this inductor value to determine if it has prefix • T intersects both the L and H re- gions, select the inductor with an H prefix. D 0.9): FIGURE 7. LM2577-12 Inductor Selection Guide . IND,DC 0.85, then calcu- FIGURE 8. LM2577-15 Inductor Selection Guide 14 ...
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... Greater ripple current causes higher peak switch currents and greater output ripple voltage; lower ripple current is achieved with larger-value inductors. The factor 30% is chosen as a convenient balance between the two extremes. FIGURE 9. LM1577-ADJ/LM2577-ADJ Inductor Selection Graph C. Select an inductor from the table of Figure 10 which cross-references the inductor codes to the part numbers of three different manufacturers ...
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Application Hints (Continued) Inductor Manufacturer’s Part Number Code Schott Pulse L47 67126980 PE - 53112 L68 67126990 PE - 92114 L100 67127000 PE - 92108 L150 67127010 PE - 53113 L220 67127020 PE - 52626 L330 67127030 PE - 52627 ...
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... Application Hints (Continued) 3. Output Voltage Selection (R1 and R2) This section is for applications using the LM1577-ADJ/ LM2577-ADJ. Skip this section if the LM1577-12/LM2577-12 or LM1577-15/LM2577-15 is being used. With the LM1577-ADJ/LM2577-ADJ, the output voltage is given by = 1.23V (1 + R1/R2) V OUT Resistors R1 and R2 divide the output down so it can be compared with the LM1577-ADJ/LM2577-ADJ internal 1 ...
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Application Hints (Continued) Note: Pin numbers shown are for TO-220 (T) package. FIGURE 13. Step-up Regulator Delivers 12V from a 5V Input FIGURE 14. Line Regulation (Typical) of Step-Up Regulator of Figure 13 A: Output Voltage Change, 100 mV/div. (AC-coupled) ...
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... A Flyback regulator can produce single or multiple output voltages that are lower or greater than the input supply volt- age. Figure 18 shows the LM1577/LM2577 used as a fly- back regulator with positive and negative regulated outputs. Its operation is similar to a step-up regulator, except the out- put switch contols the primary current of a flyback trans- former ...
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... Design Procedurefor more information regarding the selection OUT 3. Output Voltage Selection This section is for applications using the LM1577-ADJ/ LM2577-ADJ. Skip this section if the LM1577-12/LM2577-12 or LM1577-15/LM2577-15 is being used. With the LM1577-ADJ/LM2577-ADJ, the output voltage is given by = 1.23V (1 + R1/R2) V OUT www ...
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Application Hints (Continued) Dual Transformer Input Type Voltage Output Voltage = 100 µH ± 10V P ± 12V ± 5V 15V ± 10V 10V ± 10V 12V ± = 200 µ ...
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Application Hints (Continued Pulse Engineering, PE-65300 D1 1N5821 FIGURE 22. Flyback Regulator Easily Provides Dual Outputs FIGURE 23. Line Regulation (Typical) of Flyback Regulator of Figure 22 , +15V Output A: Output Voltage Change, 100 mV/div ...
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Application Hints (Continued) A: Switch pin voltage, 20 V/div B: Primary current, 2 A/div C: +15V Secondary current, 1 A/div D: +15V Output ripple voltage, 100 mV/div Horizontal: 5 µs/div FIGURE 27. Switching Waveforms of Flyback Regulator of Figure 22 ...
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... Physical Dimensions inches (millimeters) unless otherwise noted Order Number LM1577K-12/883, LM1577K-15/883, or LM1577K-ADJ/883 Order Number LM2577M-12, LM2577M-15 or LM2577M-ADJ www.national.com TO-3 Metal Can Package (K) NS Package Number K04A 0.300 Wide SO Package (M) NS Package Number M24B 24 ...
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... Physical Dimensions inches (millimeters) unless otherwise noted (Continued) Order Number LM2577N-12, LM2577N-15, or LM2577N-ADJ Order Number LM2577T-12, LM2577T-15, or LM2577T-ADJ Molded Dual-In-Line Package (N) NS Package Number N16A TO-220, Straight Leads (T) NS Package Number TO5A 25 www.national.com ...
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... Physical Dimensions inches (millimeters) unless otherwise noted (Continued) Order Number LM2577T-12 Flow LB03, LM2577T-15 Flow LB03, or LM2577T-ADJ Flow LB03 www.national.com TO-220, Bent Staggered Leads (T) NS Package Number T05D 26 ...
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... Physical Dimensions inches (millimeters) unless otherwise noted (Continued) Order Number LM2577S-12, LM2577S-15 or LM2577S-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 ...