lt3685emse-trpbf Linear Technology Corporation, lt3685emse-trpbf Datasheet
lt3685emse-trpbf
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lt3685emse-trpbf Summary of contents
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... The LT3685 is available in 10-Pin MSOP and 3mm × 3mm DFN packages with exposed pads for low thermal resistance. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. Burst Mode is a registered trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. V OUT 3 ...
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... TAPE AND REEL LT3685EDD#PBF LT3685EDD#TRPBF LT3685IDD#PBF LT3685IDD#TRPBF LT3685EMSE#PBF LT3685EMSE#TRPBF LT3685IMSE#PBF LT3685IMSE#TRPBF Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. Consult LTC Marketing for information on non-standard lead based fi nish parts. *For more information on lead free part marking, go to: For more information on tape and reel specifi ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T noted. (Note 2) PARAMETER Quiescent Current from BD Minimum Bias Voltage (BD Pin) Feedback Voltage FB Pin Bias Current (Note 3) FB Voltage Line Regulation Error Amp g m Error ...
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LT3685 W U TYPICAL PERFOR A CE CHARACTERISTICS Effi ciency 100 V = 12V 34V 24V NEC PLC-0745-5R6 800kHz OUT 50 0 0.2 0.4 ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Feedback Voltage 840 820 800 780 760 –50 – 100 125 TEMPERATURE (°C) 3685 G09 Minimum Switch On-Time 140 120 100 –50 –25 0 ...
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LT3685 W U TYPICAL PERFOR A CE CHARACTERISTICS Minimum Input Voltage 5.0 4.5 4.0 3.5 3.0 2 3.3V OUT L = 4.7μ 800kHz 2 100 1000 10000 LOAD CURRENT (A) 3685 G17 Power Good ...
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CTIO S BD (Pin 1): This pin connects to the anode of the boost Schottky diode. BD also supplies current to the internal regulator. BOOST (Pin 2): This pin is used to provide a drive ...
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LT3685 OPERATION The LT3685 is a constant frequency, current mode step- down regulator. An oscillator, with frequency set by RT, enables an RS fl ip-fl op, turning on the internal power switch. An amplifi er and comparator monitor the current ...
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APPLICATIONS INFORMATION FB Resistor Network The output voltage is programmed with a resistor divider between the output and the FB pin. Choose the 1% resis- tors according to: ⎛ ⎞ V OUT = – 1 ⎝ ...
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LT3685 APPLICATIONS INFORMATION + V V OUT – MAX MIN where V is the maximum operating input voltage, IN(MAX the output voltage, ...
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APPLICATIONS INFORMATION Table 1. Inductor Vendors VENDOR URL PART SERIES Murata www.murata.com LQH55D TDK www.componenttdk.com SLF7045 SLF10145 Toko www.toko.com D62CB D63CB D75C D75F Sumida www.sumida.com CR54 CDRH74 CDRH6D38 CR75 Of course, such a simple design guide will not always re- ...
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LT3685 APPLICATIONS INFORMATION Table 2. Capacitor Vendors VENDOR PHONE Panasonic (714) 373-7366 Kemet (864) 963-6300 Sanyo (408) 749-9714 Murata (408) 436-1300 AVX Taiyo Yuden (864) 963-6300 where MHz, and C SW OUT output capacitance in μF. Use ...
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APPLICATIONS INFORMATION Ceramic Capacitors A precaution regarding ceramic capacitors concerns the maximum input voltage rating of the LT3685. A ceramic input capacitor combined with trace or cable inductance forms a high quality (under damped) tank circuit. If the LT3685 circuit ...
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LT3685 APPLICATIONS INFORMATION BOOST and BIAS Pin Considerations Capacitor C3 and the internal boost Schottky diode (see the Block Diagram) are used to generate a boost volt- age that is higher than the input voltage. In most cases a 0.22μF ...
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APPLICATIONS INFORMATION 6.0 5.5 TO START (WORST CASE) 5.0 4.5 4.0 TO RUN 3.5 3 3.3V OUT T = 25° 8.2μ 700kHz 2 100 LOAD CURRENT (A) 8.0 TO START ...
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LT3685 APPLICATIONS INFORMATION Shorted and Reversed Input Protection If the inductor is chosen so that it won’t saturate exces- sively, an LT3685 buck regulator will tolerate a shorted output. There is another situation to consider in systems where the output ...
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APPLICATIONS INFORMATION live supply (see Linear Technology Application Note 88 for a complete discussion). The low loss ceramic capacitor, combined with stray inductance in series with the power source, forms an under damped tank circuit, and the voltage at the ...
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LT3685 APPLICATIONS INFORMATION CLOSING SWITCH SIMULATES HOT PLUG + LOW IMPEDANCE ENERGIZED 24V SUPPLY + 0.1μF + 22μF 35V AI.EI. Figure 9. A Well Chosen Input Network Prevents Input Voltage Overshoot and Ensures Reliable Operation when the LT3685 is Connected ...
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TYPICAL APPLICATIONS V IN 6.8V TO 38V TRANSIENT TO 60V* 4.7μF 470pF D: DIODES INC. DFLS240L L: TAIYO YUDEN NP06DZB6R8M *USE SCHOTTKY DIODE RATED 4.4V TO 38V TRANSIENT TO 60V* 4.7μF 470pF D: DIODES INC. DFLS240L ...
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LT3685 TYPICAL APPLICATIONS 38V TRANSIENT TO 60V* 4.7μF 330pF D1: DIODES INC. DFLS240L D2: MBR0540 L: TAIYO YUDEN NP06DZB4R7M *USE SCHOTTKY DIODE RATED 8.6V TO 22V TRANSIENT TO 36V 2.2μF 470pF D: ...
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TYPICAL APPLICATIONS V IN 15V TO 38V TRANSIENT TO 60V* 10μF 26.1k 330pF D: DIODES INC. DFLS240L L: NEC/TOKIN PLC-0755-100 *USE SCHOTTKY DIODE RATED 3.5V TO 27V 4.7μF 330pF D: DIODES INC. DFLS240L L: TAIYO YUDEN ...
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LT3685 PACKAGE DESCRIPTION 3.50 ±0.05 1.65 ±0.05 2.15 ±0.05 (2 SIDES) 0.25 ± 0.05 0.50 BSC 2.38 ±0.05 (2 SIDES) RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS NOTE: 1. DRAWING TO BE MADE A JEDEC PACKAGE OUTLINE M0-229 VARIATION OF (WEED-2). ...
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... LEAD COPLANARITY (BOTTOM OF LEADS AFTER FORMING) SHALL BE 0.102mm (.004") MAX Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...
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... I = 100μA, I <1μA, 16-Pin TSSOP OUT(MIN 0.79V 70μA, I <1μA, 10-Pin 3mm x OUT(MIN 1.26V 50μA, I <1μA, 10-Pin 3mm x OUT(MIN 1.26V 1.5mA, I <1μA, 10-Pin 3mm x OUT(MIN 0607 • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2007 3685f ...