LM3679TL-1.8EV National Semiconductor, LM3679TL-1.8EV Datasheet
LM3679TL-1.8EV
Specifications of LM3679TL-1.8EV
Related parts for LM3679TL-1.8EV
LM3679TL-1.8EV Summary of contents
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... Only three ex- ternal surface-mount components, an inductor and two ce- ramic capacitors, are required. . Typical Application Circuit FIGURE 1. Typical Low Profile Application Circuit (0.55mm max height using LM3679UR) © 2008 National Semiconductor Corporation Features ■ 16 µA typical quiescent current ■ 350 mA maximum load capability ■ ...
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... Name GND Ordering Information Order Number Spec LM3679TL - 1.8 NOPB LM3679TLX - 1.8 NOPB LM3679UR - 1.8 NOPB LM3679UR X -1.8 NOPB LM3679UR - 1.5 NOPB LM3679UR X -1.5 NOPB LM3679UR - 1.2 NOPB LM3679UR X -1.2 NOPB Contact National Semiconductor for future voltage options www.national.com Description Power supply input. Connect to the input filter capacitor (Figure 1). ...
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... Continuous Power Dissipation (Note 3) Junction Temperature (T ) J-MAX Storage Temperature Range Maximum Lead Temperature (Soldering, 10 sec.) Electrical Characteristics Limits in boldface type apply over the operating ambient temperature range (−30°C specifications apply to the LM3679TL/UR with V Symbol Parameter V Input Voltage IN V Feedback Voltage FB V ...
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Dissipation Rating Table θ JA 85°C/W (4-layer board) Block Diagram www.national.com ≤ 60°C T 25° Power Rating Power Rating 1176 mW 765 mW FIGURE 3. Simplified Functional Diagram 85°C A Power Rating 470 ...
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... Typical Performance Characteristics LM3679TL/UR, Circuit of Figure 3.6V Quiescent Supply Current vs. Supply Voltage (Switching) Switching Frequency vs. Temperature Open/Closed Loop Current Limit vs. Temperature = 1.8V 25°C, unless otherwise noted. OUT A Shutdown Current vs. Temperature 30016381 R DS(ON) 30016383 Output Voltage vs. Supply Voltage 30016349 5 30016382 vs. Temperature 30016351 ( ...
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Output Voltage vs. Temperature (V = 1.8V) OUT Output Current vs. Input Voltage at Mode Change Point (V = 1.8V) OUT Line Transient Response V = 1.8V (PWM Mode) OUT www.national.com Output Voltage vs. Output Current 30016385 Line Transient Response ...
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Load Transient Response (V = 1.8V) OUT (PFM Mode 50mA to 1mA) Mode Change by Load Transients V = 1.8V (PWM to PFM) OUT Start Up into PWM Mode V = 1.8V (Output Current = 300mA) OUT Mode Change by ...
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Operation Description DEVICE INFORMATION The LM3679, a high efficiency step down DC-DC switching buck converter, delivers a constant voltage from a single Li- Ion battery and input voltage rails from 2.5V to 5.5V such as cell phones and PDAs. Using ...
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FIGURE 5. Typical PFM Operation During PFM operation, the converter positions the output volt- age slightly higher than the nominal output voltage during PWM operation allowing additional headroom for voltage drop during a load transient from light to heavy load. ...
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Application Information INDUCTOR SELECTION There are two main considerations when choosing an induc- tor; the inductor should not saturate, and the inductor current ...
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Model LQM21PN1R0M * MIPSA2520D 1R0 LQM2HP 1R0 BRL2518T1R0M Note : *For Low Profile Solution OUTPUT CAPACITOR SELECTION A ceramic output capacitor of 10 µF, 6.3V is sufficient for most applications. Use X7R or X5R types; do not use Y5V. DC ...
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... Micro SMD PACKAGE ASSEMBLY AND USE Use of the Micro SMD package requires specialized board layout, precision mounting and careful re-flow techniques, as detailed in National Semiconductor Application Note 1112. Refer to the section "Surface Mount Technology (SMD) As- sembly Considerations". For best results in assembly, align- ment ordinals on the PC board should be used to facilitate placement of the device ...
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LM3679 and inductor to the output filter capacitor and back through ground, forming a current loop. In the second half of each cycle, current is pulled up from ground, through the LM3679 by the inductor, to the output ...
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Physical Dimensions www.national.com inches (millimeters) unless otherwise noted 5-Bump (Large) Micro SMD Package, 0.5mm Pitch NS Package Number TLA05FEA The dimensions for X1, X2, and X3 are as given 1.107 mm +/- 0.030mm X2 = 1.488 mm +/- ...
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