ltc3872ets8-trpbf Linear Technology Corporation, ltc3872ets8-trpbf Datasheet
ltc3872ets8-trpbf
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ltc3872ets8-trpbf Summary of contents
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... High switching frequency of 550kHz allows the use of a small inductor. The LTC3872 is available in an 8-lead low profi le (1mm) ThinSOT DFN package. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation and ThinSOT are trademarks of Linear Technology Corporation. SENSE All other trademarks are the property of their respective owners. ...
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... JMAX JA ORDER PART NUMBER TS8 PART MARKING LTC3872ETS8 Order Options Tape and Reel: Add #TR Lead Free: Add #PBF Lead Free Tape and Reel: Add #TRPBF Lead Free Part Marking: http://www.linear.com/leadfree/ Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T PARAMETER Oscillator Frequency Normal Operation Gate Drive Rise Time Gate Drive Fall Time Peak Current Sense Voltage Default Internal Soft-Start Time Note 1: Stresses beyond those listed under Absolute Maximum ...
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LTC3872 W U TYPICAL PERFOR A CE CHARACTERISTICS Shutdown (V) IN 3872 G04 Gate Drive Rise and Fall ...
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CTIO S (TS8/DD8) IPRG (Pin 1/Pin 4): Current Sense Limit Select Pin. I (Pin 2/Pin 3): It serves as the error amplifi er com- TH pensation point. Nominal voltage range for this pin is 0.7V ...
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LTC3872 U OPERATIO Main Control Loop The LTC3872 constant frequency, current SENSE mode controller for DC/DC boost, SEPIC and fl yback converter applications. The LTC3872 is distinguished from conventional current mode controllers because the current control ...
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U U APPLICATIO S I FOR ATIO Output Voltage Programming The output voltage is set by a resistor divider according to the following formula: ⎛ ⎞ • 1 ⎝ ⎜ ⎠ ...
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LTC3872 U U APPLICATIO S I FOR ATIO mode gain and avoid subharmonic oscillation recom- mended that the ripple current in the inductor fall in the range of 20% to 40% of the maximum average current. For example, ...
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U U APPLICATIO S I FOR ATIO the maximum drain current (I D(MAX) thermal resistances (R and R TH(JC) TH(JA threshold MOSFETs should be used when input GS-RATED voltage is high, otherwise if low input voltage operation is ...
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LTC3872 U U APPLICATIO S I FOR ATIO result, some iterative calculation is normally required to determine a reasonably accurate value. Since the controller is using the MOSFET as both a switching and a sensing element, care should be taken ...
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U U APPLICATIO S I FOR ATIO where: χ ⎛ ⎞ MAX ( ) = + ⎜ ⎟ • IN PEAK ( ) ⎝ ⎠ – D MAX For the bulk C component, which ...
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LTC3872 U U APPLICATIO S I FOR ATIO Input Capacitor Selection The input capacitor of a boost converter is less critical than the output capacitor, due to the fact that the inductor is in series with the input and the ...
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U U APPLICATIO S I FOR ATIO Power MOSFET Selection. 3. The losses in the inductor are simply the DC input cur- rent squared times the winding resistance. Expressing this loss as a function of the output current yields: 2 ...
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LTC3872 U U APPLICATIO S I FOR ATIO 3. Assuming a MOSFET junction temperature of 125°C, the room temperature MOSFET R than: 1 ≤ • SENSE MAX ( ) χ ⎛ ⎝ ...
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TYPICAL APPLICATIONS 2.2nF 23.2k 100pF 11. COUPLED STEP FROM 500mA TO 1.5A High Effi ciency 3.3V Input, 12V Output Boost Converter 4.7M 0.1μF I RUN/ IPRG 2.2μH LTC3872 GND SW V NGATE M1 PDS1040 ...
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LTC3872 TYPICAL APPLICATIONS High Effi ciency 5V Input, 12V Output Boost Converter 4.7M 1nF 2.2nF 11k I RUN/ 100p IPRG LTC3872 GND SW V NGATE FB 11.8k 1% 107k 1% COUT1: TAIYO YUDEN TMK325BJ226MM L1: TOKO D124C ...
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TYPICAL APPLICATIONS 63.4k 2.2nF 1% V 12.1k 1% Soft-Start RUN/SS 5V/DIV I L 5A/DIV V OUT 20V/DIV 40ms/DIV High Effi ciency 5V Input, 48V Output Boost Converter 1M 0.33μF I RUN/ IPRG IN L1 10μH LTC3872 GND ...
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LTC3872 PACKAGE DESCRIPTIO 0.61 ±0.05 (2 SIDES) 2.55 ±0.05 1.15 ±0.05 0.25 ± 0.05 RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS PIN 1 BAR TOP MARK (SEE NOTE 6) 0.200 REF NOTE: 1. DRAWING CONFORMS TO VERSION (WECD-1) IN JEDEC PACKAGE ...
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... MOLD FLASH SHALL NOT EXCEED 0.254mm 6. JEDEC PACKAGE REFERENCE IS MO-193 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. U ...
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... Step-Up or Step Down, 600kHz, SSOP-16, SSOP-28 Optimized for Driving 6V MOSFETs ThinSOT ● www.linear.com 10μ OUT 5V C OUT 2A 100μF ×2 3872 TA02 16V, Miniature Design IN ≤ ≤ 36V IN LT 0407 REV A • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2007 3872fa ...