LT3695EMSE-3.3#PBF Linear Technology, LT3695EMSE-3.3#PBF Datasheet
LT3695EMSE-3.3#PBF
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LT3695EMSE-3.3#PBF Summary of contents
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... Automotive Entertainment Systems n Distributed Supply Regulation Industrial Supplies n L, LT, LTC, LTM, Burst Mode, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. TYPICAL APPLICATION 5V Step-Down Converter V IN 6.9V TO 36V TRANSIENT TO 60V 2.2μ ...
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... WITHOUT EXPOSED PAD SOLDERED JA ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL LT3695EMSE#PBF LT3695EMSE#TRPBF LT3695IMSE#PBF LT3695IMSE#TRPBF LT3695HMSE#PBF LT3695HMSE#TRPBF LT3695EMSE-3.3#PBF LT3695EMSE-3.3#TRPBF 369533 LT3695IMSE-3.3#PBF LT3695IMSE-3.3#TRPBF LT3695HMSE-3.3#PBF LT3695HMSE-3.3#TRPBF 369533 LT3695EMSE-5#PBF LT3695EMSE-5#TRPBF LT3695IMSE-5#PBF LT3695IMSE-5#TRPBF LT3695HMSE-5#PBF LT3695HMSE-5#TRPBF Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. *The temperature grade is identifi label on the shipping container. ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T PARAMETER CONDITIONS Minimum Operating Voltage (Note 6) LT3695 LT3695-3.3 V OUT1,2 LT3695-5 V OUT1,2 V Overvoltage Lockout IN Quiescent Current from RUN/SS LT3695 ...
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LT3695 Series ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T PARAMETER CONDITIONS Switch V I CESAT SW DA Pin Current to Stop OSC Switch Leakage Current V SW Boost Schottky Diode Voltage Drop I BSD Boost Schottky Diode ...
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TYPICAL PERFORMANCE CHARACTERISTICS Effi ciency (V = 5V, SYNC = 0V) OUT 10μ 800kHz 12V 34V 24V 0.1 ...
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LT3695 Series TYPICAL PERFORMANCE CHARACTERISTICS Switch Current Limit 1.9 1.7 SYNC < 0.3V 1.5 1.3 SYNC > 0.8V OR CLOCKED 1.1 0.9 0.7 0 100 DUTY CYCLE (%) 3695 G10 BOOST Pin Current 35 30 ...
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TYPICAL PERFORMANCE CHARACTERISTICS Frequency Foldback: LT3695-5 1200 R = 29.4k RT 1000 800 600 400 200 OUTPUT VOLTAGE (V) 3695 G19 RUN/SS Pin Current ...
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LT3695 Series TYPICAL PERFORMANCE CHARACTERISTICS Minimum Input Voltage 6 OUT L = 10μ 800kHz 6.0 5.5 5.0 4 100 LOAD CURRENT (mA) 3695 G28 Maximum V for Full Frequency ...
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PIN FUNCTIONS (LT3695/LT3695-3.3, LT3695-5) PGND (Pin 1, Exposed Pad Pin 17/Pin 1, Exposed Pad Pin 17): This is the power ground used by the catch diode (D1 in the Block Diagram) when its anode is connected to the DA pin. ...
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LT3695 Series BLOCK DIAGRAM INTERNAL 0.8V REF SYNC 7 RUN/SS 5 SOFT-START 0.720V – GND INTERNAL 0.8V ...
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OPERATION The LT3695 series are constant-frequency, current mode step-down regulators. An oscillator, with frequency set enables an RS fl ip-fl op, turning on the internal power T switch. An amplifi er and comparator monitor the current fl ...
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LT3695 Series APPLICATIONS INFORMATION FB Resistor Network (LT3695) The output voltage of the LT3695 is programmed with a resistor divider between the output and the FB pin. Choose the resistor values according to: ⎛ ⎞ − OUT R ...
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APPLICATIONS INFORMATION A good choice of switching frequency should allow an adequate input voltage range (see Input Voltage Range sec- tion) and keep the inductor and capacitor values small. Input Voltage Range The minimum input voltage is determined by either ...
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LT3695 Series APPLICATIONS INFORMATION Inductor Selection and Maximum Output Current A good fi rst choice for the inductor value is • OUT where f is the switching ...
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APPLICATIONS INFORMATION Choosing an inductor value so that the ripple current is small will allow a maximum output current near the switch current limit. Table 2. Inductor Vendors VENDOR URL PART SERIES Murata www.murata.com LQH55D TDk www.componenttdk.com SLF7045 SLF10145 Toko ...
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LT3695 Series APPLICATIONS INFORMATION Table 3. 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 Low ESR is important, so choose one that is intended for use in ...
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APPLICATIONS INFORMATION Audible Noise Ceramic capacitors are small, robust and have very low ESR. However, ceramic capacitors can sometimes cause problems when used with the LT3695 regulators due to their piezoelectric nature. When in Burst Mode operation, the LT3695 regulators’ ...
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LT3695 Series APPLICATIONS INFORMATION Low Ripple Burst Mode Operation The LT3695 regulators are capable of operating in either low ripple Burst Mode operation or pulse-skipping mode which are selected using the SYNC pin. See the Synchro- nization section for more ...
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APPLICATIONS INFORMATION BOOST LT3695 GND PGND (4a) For V > 2.8V 4. OUT IN(MIN BOOST LT3695 D1 DA GND PGND ...
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LT3695 Series APPLICATIONS INFORMATION This reduces the minimum input voltage to approximately 300mV above higher load currents, the inductor OUT current is continuous and the duty cycle is limited by the maximum duty cycle of the LT3695 ...
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APPLICATIONS INFORMATION then the LT3695 regulators’ internal circuitry will pull its quiescent current through its SW pin. This is fi your system can tolerate a few mA in this state. If you ground the RUN/SS pin, the SW ...
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LT3695 Series APPLICATIONS INFORMATION High Temperature Considerations The PCB must provide heat sinking to keep the LT3695 regulators cool. The exposed pad on the bottom of the package may be soldered to a copper area which should be tied to ...
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APPLICATIONS INFORMATION Table 5: Effects of Pin Shorts PINS EFFECT PGND-DA No effect if V < IN(MAX) SW-RUN/SS The result of this short depends on the load resistance and on R3 (Figure 10). See the following discussion. RUN/SS-RT ...
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LT3695 Series APPLICATIONS INFORMATION + R2, and the BD pin (if connected to V the LT3695 and the OUT1,2 pins in the LOAD case of the LT3695-3.3 and LT3695-5. Since this causes V to rise, ...
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... Make sure not to exceed V to RUN/SS as shown details) during start-up or overload conditions. Other Linear Technology Publications Application Notes 19, 35 and 44 contain more detailed descriptions and design information for buck regulators and other switching regulators. The LT1376 data sheet ...
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LT3695 Series TYPICAL APPLICATIONS Fully Tolerant 3.3V Step-Down Converter with Soft-Start 28.5V TRANSIENT TO 36V 2.2μ 3.6V TO 25V 26 324k RUN/SS BOOST LT3695 47Ω ...
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TYPICAL APPLICATIONS V IN 10V TO 16.5V TRANSIENT TO 36V 2.2μF Fully Tolerant 5V Step-Down Converter with Soft-Start 365k V IN RUN/SS BOOST V C LT3695 47Ω 13.3k 9.76k SYNC 100k 0.22μF 680pF GND PGND f = 2MHz ...
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LT3695 Series PACKAGE DESCRIPTION 2.845 0.102 (.112 .004) 5.23 (.206) MIN 0.305 0.038 (.0120 .0015) TYP RECOMMENDED SOLDER PAD LAYOUT DETAIL “A” 0.254 (.010) GAUGE PLANE 0.18 (.007) NOTE: 1. DIMENSIONS IN MILLIMETER/(INCH) 2. DRAWING NOT TO SCALE 3. DIMENSION ...
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... All Sections Revised to Include LT3695-3.3 and LT3695-5 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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... V = 1.2V 1.9mA, I OUT(MAX 5.5V to 60V 1.2V 2.5mA, I OUT(MAX 1109 REV A • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2009 = 2μA, Q < 1μA, < 1μA, < 1μA, = 1μA, = 2μA, < 10μA, < 1μA, < 1μA, < 1μA, < 1μA, < 1μA, < ...