LP3871EMPX-1.8 NSC [National Semiconductor], LP3871EMPX-1.8 Datasheet

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LP3871/LP3874 0.8A Fast Ultra Low Dropout Linear Regulators General Description The LP3871/LP3874 series of fast ultra low-dropout linear regulators operate from a +2.5V to +7.0V input supply. Wide range of preset output voltage options are available. These ultra low dropout ...

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Typical Application Circuits *SD must be pulled high through a 10kΩ pull-up resistor. See application hints for more information. Connection Diagrams Top View TO220-5 Package Bent, Staggered Leads 20063190 Top View SOT223-5 Package www.national.com (Continued) 20063105 TO263-5 Package 2 20063145 ...

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Pin Description for TO220-5 and TO263-5 Packages Pin # Name GND 4 V OUT 5 ERROR Pin Description for SOT223-5 Package Pin # Name OUT 4 ERROR ...

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... Error Flag 5.0 LP3871EMPX-5.0 0.8A, Error Flag 3.3 LP3871EMP-3.3 0.8A, Error Flag 3.3 LP3871EMPX-3.3 0.8A, Error Flag 2.5 LP3871EMP-2.5 0.8A, Error Flag 2.5 LP3871EMPX-2.5 0.8A, Error Flag 1.8 LP3871EMP-1.8 0.8A, Error Flag 1.8 LP3871EMPX-1.8 0.8A, Error Flag www.national.com Description Package (Current, Option) Type TO263-5 TO263-5 TO263-5 TO263-5 TO263-5 TO263-5 TO263-5 TO263-5 TO263-5 TO263-5 TO263-5 TO263-5 TO263-5 ...

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Ordering Information (Continued) TABLE 1. Package Marking and Ordering Information (Continued) Output Order Number Voltage (Current, Option) 5.0 LP3874EMP-5.0 0.8A, SENSE 5.0 LP3874EMPX-5.0 0.8A, SENSE 3.3 LP3874EMP-3.3 0.8A, SENSE 3.3 LP3874EMPX-3.3 0.8A, SENSE 2.5 LP3874EMP-2.5 0.8A, SENSE 2.5 LP3874EMPX-2.5 0.8A, ...

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Block Diagrams www.national.com LP3871 20063103 LP3874 20063129 6 ...

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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. Storage Temperature Range Lead Temperature (Soldering, 5 sec.) ESD Rating (Note 3) Power Dissipation (Note 2) Input Supply Voltage ...

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Electrical Characteristics LP3871/LP3874 (Continued) Limits in standard typeface are for T Unless otherwise specified Symbol Parameter Shutdown Input V Shutdown Threshold SDT T Turn-off delay dOFF T Turn-on delay dON I SD Input Current SD Error ...

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Typical Performance Characteristics C = 10µF, S/D pin is tied OUT Dropout Voltage vs Output Load Current Shutdown I vs Junction Temperature Q DC Load Reg. vs Junction Temperature Unless ohterwise specified ...

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Typical Performance Characteristics C = 10µF, S/D pin is tied Noise vs Frequency Load Transient Response 100µF, OSCON IN OUT Load Transient Response 10µF, TANTALUM IN OUT www.national.com ...

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Application Hints V RESTRICTIONS FOR PROPER START- prevent misoperation, ensure that V before start-up is initiated. This scenario can occur in sys- tems with a backup battery using reverse-biased "blocking" diodes which may allow enough leakage current to ...

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Application Hints (Continued) Any applications using aluminum electrolytics should be thoroughly tested at the lowest ambient operating tempera- ture where ESR is maximum. PCB LAYOUT Good PC layout practices must be used or instability can be induced because of ground ...

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Application Hints (Continued) SENSE PIN In applications where the regulator output is not very close to the load, LP3874 can provide better remote load regulation using the SENSE pin. Figure 2 depicts the advantage of the SENSE option. LP3871 regulates ...

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Application Hints (Continued) DROPOUT VOLTAGE The dropout voltage of a regulator is defined as the minimum input-to-output differential required to stay within 2% of the nominal output voltage. For CMOS LDOs, the dropout volt- age is the product of the ...

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Application Hints (Continued) FIGURE 5. θ vs Copper(1 Ounce) Area for SOT-223 JA package The following figures show different layout scenarios for SOT-223 package. FIGURE 6. SCENARIO A, θ 20063191 FIGURE 7. SCENARIO B, θ 15 20063192 = 148˚C/W JA ...

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Physical Dimensions TO220 5-lead, Molded, Stagger Bend Package (TO220-5) For Order Numbers, refer to the “Ordering Information” section of this document. www.national.com inches (millimeters) unless otherwise noted NS Package Number T05D 16 ...

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Physical Dimensions inches (millimeters) unless otherwise noted (Continued) TO263 5-Lead, Molded, Surface Mount Package (TO263-5) For Order Numbers, refer to the “Ordering Information” section of this document. NS Package Number TS5B 17 www.national.com ...

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Physical Dimensions SOT223, 5-Lead, Molded, Surface Mount Package (SOT223-5) For Order Numbers, refer to the “Ordering Information” section of this document. LIFE SUPPORT POLICY NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS ...