LM2587T-ADJ/NOPB National Semiconductor, LM2587T-ADJ/NOPB Datasheet
LM2587T-ADJ/NOPB
Specifications of LM2587T-ADJ/NOPB
*LM2587T-ADJ/NOPB
LM2587T-ADJ
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LM2587T-ADJ/NOPB Summary of contents
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... Typical Applications ■ Flyback regulator ■ Multiple-output regulator ■ Simple boost regulator ■ Forward converter NSC Package Drawing T05D LM2587T-3.3, LM2587T-5.0, LM2587T-12, LM2587T-ADJ TS5B LM2587S-3.3, LM2587S-5.0, LM2587S-12, LM2587S-ADJ TS5B LM2587SX-3.3, LM2587SX-5.0, LM2587SX-12, LM2587SX-ADJ 12316 February 2, 2010 1231601 Order Number www.national.com ...
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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. Input Voltage Switch Voltage Switch Current (Note 2) Compensation Pin Voltage Feedback Pin Voltage Storage Temperature Range Lead Temperature (Soldering, 10 sec.) LM2587-3.3 ...
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LM2587-5.0 Electrical Characteristics Specifications with standard type face are for T Range. Unless otherwise specified, V Symbol Parameters SYSTEM PARAMETERS Test Circuit of V Output Voltage V OUT I LOAD ΔV Line Regulation V / OUT ΔV I LOAD IN ...
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LM2587-ADJ Electrical Characteristics Specifications with standard type face are for T Range. Unless otherwise specified, V Symbol Parameters SYSTEM PARAMETERS Test Circuit of V Output Voltage V OUT I ΔV Line Regulation V / OUT Δ ΔV Load ...
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Symbol Parameters I Error Amp (Note EAO Output Current (Source or Sink) I Soft Start Current Maximum Duty Cycle R (Note I Switch Leakage Switch Off L Current V V Switch Sustaining dV/dT = 1.5V/ns SUS ...
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Typical Performance Characteristics Supply Current vs Temperature ΔReference Voltage vs Supply Voltage Current Limit vs Temperature www.national.com 1231648 1231650 Feedback Pin Bias Current vs Temperature 1231652 6 Reference Voltage vs Temperature 1231649 Supply Current vs Switch Current 1231651 1231653 ...
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Switch Saturation Voltage vs Temperature 1231654 Oscillator Frequency vs Temperature 1231656 Error Amp Voltage Gain vs Temperature 1231658 Switch Transconductance vs Temperature Error Amp Transconductance vs Temperature Short Circuit Frequency vs Temperature 7 1231655 1231657 1231659 www.national.com ...
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... TO-263 (S) Top View Block Diagram For Fixed Versions3.3V 3.4k 2k5V 6.15k 2k12V 8.73k 1kFor Adj. VersionR1 = Short (0Ω), R2 = Open www.national.com 1231603 Order Number LM2587T-3.3, LM2587T-5.0, LM2587T-12 or LM2587T-ADJ See NS Package Number T05D 1231605 Order Number LM2587S-3.3, LM2587S-5.0, LM2587S-12 or LM2587S-ADJ See NS Package Number TS5B FIGURE 1 ...
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Test Circuits —100 μF, 25V Aluminum ElectrolyticC —0.1 μF CeramicT—22 μH, 1:1 Schott #67141450D—1N5820C C IN1 IN2 μF CeramicR —2k C —100 μF, 25V Aluminum ElectrolyticC —0.1 μF CeramicL—15 μH, Renco #RL-5472-5D—1N5820C C IN1 IN2 CeramicR —2kFor 12V Devices: R ...
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Flyback Regulator Operation The LM2587 is ideally suited for use in the flyback regulator topology. The flyback regulator can produce a single output voltage, such as the one shown in Figure voltages. In Figure 4, the flyback regulator generates an ...
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Typical Performance Characteristics A: Switch Voltage, 10 V/divB: Switch Current, 5 A/divC: Output Rectifier Current, 5 A/divD: Output Ripple Voltage, 100 mV/div AC-Coupled Horizontal: 2 μs/div Typical Flyback Regulator Applications Figures 11, 12 show six typical flyback ...
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FIGURE 7. Single-Output Flyback Regulator FIGURE 8. Single-Output Flyback Regulator 12 1231613 1231614 ...
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FIGURE 9. Single-Output Flyback Regulator FIGURE 10. Dual-Output Flyback Regulator 13 1231615 1231616 www.national.com ...
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FIGURE 11. Dual-Output Flyback Regulator FIGURE 12. Triple-Output Flyback Regulator 14 1231617 1231618 ...
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TRANSFORMER SELECTION (T) Figure 13 lists the standard transformers available for flyback regulator applications. Included in the table are the turns ratio Applications Figure 7 Transformers T1 V 4V– 3.3V OUT1 I (Max) 1.8A OUT1 ...
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TRANSFORMER FOOTPRINTS Figure 15 Figure 16 Figure 17 Figure 18 Figure 19 Figure 20 Figure 21 Figure 22 Figure 23 Figure 24 Figure 25 Figure 26 Figure 27 Figure 28 Figure 29 Figure 30 Figure 31 Figure 32 show the ...
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T3 1231638 Top View FIGURE 23. Pulse PE-68421 (Surface Mount) T4 1231639 Top View FIGURE 24. Pulse PE-68422 (Surface Mount) T1 1231640 Top View FIGURE 25. Renco RL-5530 T2 1231641 Top View FIGURE 26. Renco RL-5531 T3 Top View FIGURE ...
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Step-Up (Boost) Regulator Operation Figure 33 shows the LM2587 used as a step-up (boost) reg- ulator. This is a switching regulator that produces an output voltage greater than the input supply voltage. A brief explanation of how the LM2587 Boost ...
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Typical Performance Characteristics A: Switch Voltage, 10 V/divB: Switch Current, 5 A/divC: Inductor Current, 5 A/divD: Output Ripple Voltage, 100 mV/div, AC-Coupled Horizontal: 2 μs/div FIGURE 35. V Typical Boost Regulator Applications Figure 36 and Figures 38, 39 and Figure ...
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Figure 37 contains a table of standard inductors, by part num- ber and corresponding manufacturer, for the fixed output regulator of Figure 36. Coilcraft (Note R4793-A Note 19: Coilcraft Inc.,: Phone: (800) 322-2645 1102 Silver Lake Road, Cary, IL 60013: ...
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LM2587 will require a heat sink in these applications. The size of the heat sink will depend on the maximum ambient temperature. To calculate the thermal resistance of the IC and the size of the heat sink needed, see ...
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Application Hints PROGRAMMING OUTPUT VOLTAGE (SELECTING R AND Referring to the adjustable regulator in voltage is programmed by the resistors R lowing formula OUT REF 1 2 Resistors ...
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In addition, a small bypass capacitor is required due to the noise generated by the input current pulses. To eliminate the noise, insert a 1.0 μF ceramic capacitor between V ground as close as possible to the device. SWITCH VOLTAGE ...
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OUTPUT VOLTAGE LIMITATIONS The maximum output voltage of a boost regulator is the max- imum switch voltage minus a diode drop flyback regula- tor, the maximum output voltage is determined by the turns ratio, N, and the duty ...
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... To further simplify the flyback regulator design procedure, is the output voltage, National Semiconductor is making available computer design ∑ software. Switchers Made Simple software is available the sum of LOAD a (3½ ...
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... Physical Dimensions www.national.com inches (millimeters) unless otherwise noted Order Number LM2587T-3.3, LM2587T-5.0, LM2587T-12 or LM2587T-ADJ NS Package Number T05D 26 ...
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Order Number LM2587S-3.3, LM2587S-5.0, LM2587S-12 or LM2587S-ADJ NS Package Number TS5B 27 www.national.com ...
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