LTC1771I Linear Technology, LTC1771I Datasheet

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... Figure 1. High Efficiency Step-Down Converter 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 represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. Low Quiescent Current ...

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... OFF V Mode Pin Threshold MODE 2 U (Note 1) Junction Temperature (Note 2) ............................ 125 C Operating Temperature Range (Note 3) + 0.3V) LTC1771E ......................................... – LTC1771I ......................................... – Storage Temperature Range ................. – 150 C + 0.3V) Lead Temperature (Soldering, 10 sec).................. 300 0.3V ORDER PART NUMBER RUN/SS ...

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... Note 3: The LTC1771E is guaranteed to meet performance specifications from Specifications over the – operating temperature range are assured by design, characterization and correlation with statistical process controls. The LTC1771I is guaranteed and tested over the – operating temperature range. U ...

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LTC1771 U U FUNCTIONAL BLOCK DIAGRA RUN/SS 1 MODE (BURST ENABLE 1.23V ON EA – 10% CURRENT V OUT * GND – 4 ...

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U OPERATIO (Refer to Functional Block Diagram) Main Control Loop The LTC1771 uses a constant off-time, current mode step-down architecture. During normal operation, the P-channel MOSFET is turned on at the beginning of each cycle and turned off when the ...

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LTC1771 APPLICATIO S I FOR ATIO The basic LTC1771 application circuit is shown in Figure 1 on the first page. External component selection is driven by the load requirement and begins with the selection ...

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U U APPLICATIO S I FOR ATIO Power MOSFET Selection An external P-channel power MOSFET must be selected for use with the LTC1771. The main selection criteria for the power MOSFET are the threshold voltage V the “on” resistance R ...

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... In surface mount applications multiple capacitors may have to be paralleled to meet the ESR or RMS current handling requirements of the application. Aluminum OPTI-LOOP is a trademark of Linear Technology Corporation electrolytics and dry tantalum capacitors are both available in surface mount configurations. In case of tantalum critical that the capacitors are surge tested for use in switching power supplies ...

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U U APPLICATIO S I FOR ATIO between the P-channel MOSFET in series with R and the output diode. The MOSFET R multiplied by the duty cycle can be summed with the 2 resistance obtain I R ...

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LTC1771 APPLICATIO S I FOR ATIO Minimum On-Time Considerations Minimum on-time t is the smallest amount of time ON(MIN) that the LTC1771 is capable of turning the top MOSFET on and off again determined by ...

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U U APPLICATIO S I FOR ATIO Design Example As a design example, assume V = 10V (nominal 15V , V = 3.3V, and I = 2A. With this informa- (MAX) OUT MAX tion, we can easily calculate ...

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LTC1771 U TYPICAL APPLICATIO S 3.3V to 2.5V/1A Regulator with Burst Mode Operation Enabled 0. 220pF 10k 0. 220pF 10k RUN/SS MODE 7 I ...

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U TYPICAL APPLICATIO S 0. RUN/SS 220pF 10k GND 1M 1% 0.01 F 220pF 10k 1M 1% Low Dropout Single Cell Lithium-Ion MODE MODE 7 SENSE TH 1000pF LTC1771 6 ...

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LTC1771 U TYPICAL APPLICATIONS 0. RUN/SS 220pF 10k GND 1M 1% U1: INTERNATIONAL RECTIFIER TM FETKY IRF7422D2 0. RUN/SS 220pF 10k GND 1M ...

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PACKAGE DESCRIPTIO 0.007 (0.18) * DIMENSION DOES NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS. MOLD FLASH, PROTRUSIONS OR GATE BURRS SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE ** DIMENSION DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSIONS. INTERLEAD FLASH OR ...

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... Monolithic 400mA, MS8 Q LTC1174 with Internal Schottky Diode Constant Frequency 10V V 95% DC, 3.5V to 36V Quiescent Current RMS 30 A Quiescent Current RMS SOT-23, 2. 1771i LT/TP 0200 4K • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 2000 , MS8 IN Noise Noise ...