LM2577-ADJ National Semiconductor, LM2577-ADJ Datasheet
LM2577-ADJ
Specifications of LM2577-ADJ
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LM2577-ADJ Summary of contents
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... LM1577/LM2577 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 versions: 12V, 15V, and adjustable. Requiring a minimum number of external components, these regulators are cost effective, and simple to use ...
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... See NS Package Number N16A TO-263 (S) 5-Lead Surface-Mount Package Top View www.national.com (Continued) 01146806 *No internal Connection Order Number LM2577M-12, LM2577M-15, Order Number LM2577S-12, LM2577S-15, 01146832 4-Lead TO-3 (K) 01146808 Bottom View Order Number LM1577K-12/883, LM1577K-15/883, or LM1577K-ADJ/883 See NS Package Number K04A 2 24-Lead Surface Mount (M) ...
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... A Typical Application Note: Pin numbers shown are for TO-220 (T) package. Output Voltage 12V 15V LM2577M-12 LM2577M-15 LM2577M-ADJ LM2577N-12 LM2577N-15 LM2577N-ADJ LM2577S-12 LM2577S-15 LM2577S-ADJ LM2577T-12 LM2577T-15 LM2577T-ADJ LM2577T-12 LM2577T-15 LM2577T-ADJ Flow LB03 Flow LB03 LM1577K-12/883LM1577K-15/883 3 NSC ADJ Package Package Drawing M24B SO N16A ...
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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, V Symbol Parameter SYSTEM PARAMETERS Circuit of Figure 1 (Note 6) V ...
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... Electrical Characteristics—LM1577-12, LM2577-12 Specifications with standard type face are for T Range. Unless otherwise specified, V Symbol Parameter DEVICE PARAMETERS A Error Amp VOL Voltage Gain Error Amplifier Output Swing Error Amplifier Output Current I Soft Start Current SS D Maximum Duty Cycle Switch Transconductance ...
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... Electrical Characteristics—LM1577-15, LM2577-15 Specifications with standard type face are for T Range. Unless otherwise specified, V Symbol Parameter DEVICE PARAMETERS I Input Supply Current S V Input Supply UV Undervoltage Lockout f Oscillator Frequency O V Output Reference REF Voltage Output Reference Voltage Line Regulation R Feedback Pin Input ...
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... Specifications with standard type face are for T Range. Unless otherwise specified, V Symbol Parameter DEVICE PARAMETERS NPN Switch Current Limit Electrical Characteristics—LM1577-ADJ, LM2577-ADJ Specifications with standard type face are for T Range. Unless otherwise specified, V Symbol Parameter SYSTEM PARAMETERS Circuit of Figure 3 (Note 6) V ...
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... Electrical Characteristics—LM1577-ADJ, LM2577-ADJ Specifications with standard type face are for T Range. Unless otherwise specified, V Symbol Parameter DEVICE PARAMETERS Error Amplifier Output Swing Error Amp Output Current I Soft Start Current SS D Maximum Duty Cycle ∆I / Switch SWITCH ∆V Transconductance COMP I Switch Leakage ...
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... Electrical Characteristics—LM1577-ADJ, LM2577-ADJ Note 8: Junction to ambient thermal resistance with approximately 1 square inch of pc board copper surrounding the leads. Additional copper area will lower thermal resistance further. See thermal model in “Switchers Made Simple” software. Note 9: If the TO-263 package is used, the thermal resistance can be reduced by increasing the PC board copper area thermally connected to the package. Using 0.5 square inches of copper area, θ ...
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Typical Performance Characteristics Error Amp Transconductance vs Temperature Error Amp Transconductance vs Temperature Error Amp Voltage Gain vs Temperature www.national.com (Continued) Error Amp Transconductance 01146840 01146842 01146844 10 vs Temperature 01146841 Error Amp Voltage Gain vs Temperature 01146843 Error Amp ...
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Typical Performance Characteristics Quiescent Current vs Temperature Current Limit vs Temperature Switch Saturation Voltage vs Switch Current (Continued) 01146846 Current Limit Response 01146848 Switch Transconductance 01146850 11 Quiescent Current vs Switch Current 01146847 Time vs Overdrive 01146849 vs Temperature 01146851 ...
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Typical Performance Characteristics Feedback Pin Bias Current vs Temperature Maximum Power Dissipation (TO-263) (Note 9) www.national.com (Continued) 01146852 01146831 12 Oscillator Frequency vs Temperature 01146853 ...
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... C = Sprague Type 673D 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 C = Sprague Type 673D OUT Electrolytic 680 µF, 20V Note: Pin numbers shown are for TO-220 (T) package FIGURE 2 ...
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... LM1577-ADJ, LM2577-ADJ Test Circuit L = 415-0930 (AIE any manufacturer C = Sprague Type 673D OUT Electrolytic 680 µF, 20V R1 = 48.7k in series with 511Ω (1 5.62k (1%) Note: Pin numbers shown are for TO-220 (T) package FIGURE 3. Circuit Used to Specify System Parameters for ADJ Versions Application Hints Note: Pin numbers shown are for TO-220 (T) package *Resistors are internal to LM1577/LM2577 for 12V and 15V versions ...
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... Application Hints (Continued) STEP-UP (BOOST) REGULATOR 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 directly to the regulator output ...
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... Application Hints (Continued) ditions for which the LM1577/LM2577 output switch would be operating beyond its switch current rating. The minimum operating voltage for the LM1577/LM2577 is 3.5V. From here, proceed to step C. 2. For Adjustable version Preliminary calculations: The inductor selection is based on the calculation of the following three parameters: , the maximum switch duty cycle (0 ≤ ...
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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 1.23V (1 + R1/R2) 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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... FLYBACK REGULATOR A Flyback regulator can produce single or multiple output voltages that are lower or greater than the input supply voltage. Figure 18 shows the LM1577/LM2577 used as a flyback regulator with positive and negative regulated out- puts. Its operation is similar to a step-up regulator, except the output switch contols the primary current of a flyback trans- former ...
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... Application Hints (Continued Pulse Engineering, PE-65300 D1 1N5821 FIGURE 18. LM1577-ADJ/LM2577-ADJ Flyback Regulator with www.national.com 01146818 ± Outputs 22 ...
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... At this point, refer to this same section in the Step-Up Regulator Design Procedurefor more information regard- ing 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 D ∆I P ...
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... Application Hints (Continued) step-up regulator, and this requires a larger bypass capacitor to decouple the LM1577/LM2577 V IN most applications, a low ESR, 1.0 µF cap will be sufficient connected very close to the V IN Transformer Input Type Voltage L = 100 µ 10V 10V 200 µH 10V 0.5 ...
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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 B: ...
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Application Hints (Continued) FIGURE 25. Line Regulation (Typical) of Flyback Regulator of Figure 22, −15V Output 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 ...
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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 TO-3 Metal Can Package (K) NS Package Number K04A 0.300 Wide SO Package (M) NS Package Number M24B 27 www.national.com ...
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... Physical Dimensions Order Number LM2577N-12, LM2577N-15, or LM2577N-ADJ Order Number LM2577T-12, LM2577T-15, or LM2577T-ADJ www.national.com inches (millimeters) unless otherwise noted (Continued) Molded Dual-In-Line Package (N) NS Package Number N16A TO-220, Straight Leads (T) NS Package Number TO5A 28 ...
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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 TO-220, Bent Staggered Leads (T) NS Package Number T05D 29 www.national.com ...
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... Physical Dimensions inches (millimeters) unless otherwise noted (Continued) Order Number LM2577S-12, LM2577S-15 or LM2577S-ADJ National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications. ...
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