LTC1771EMS8 Linear Technology, LTC1771EMS8 Datasheet
LTC1771EMS8
Specifications of LTC1771EMS8
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LTC1771EMS8 Summary of contents
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... LTC1771 ideal for a wide variety of battery-powered appli- cations where maximizing battery life is important. The LTC1771’s availability in both 8-lead MSOP and SO packages provides for a minimum area solution. , LTC and LT are registered trademarks of Linear Technology Corporation. Burst Mode is a trademark of Linear Technology Corporation ...
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... Operating Temperature Range (Note 3) + 0.3V)* LTC1771E ......................................... – LTC1771I ......................................... – Storage Temperature Range ................. – 150 C + 0.3V)* Lead Temperature (Soldering, 10 sec).................. 300 0.3V)* IN *RUN/SS and SENSE cannot exceed 20V ORDER PART NUMBER RUN/SS 1 LTC1771EMS8 GND 4 MS8 PART MARKING 8-LEAD PLASTIC SO LTKD T JMAX CONDITIONS (Note 5) (Note 5) V ...
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ELECTRICAL CHARACTERISTICS The denotes specifications which apply over the full operating temperature range, otherwise specifications are 10V open unless otherwise specified. IN RUN SYMBOL PARAMETER V RUN/SS Pin Threshold RUN/SS I ...
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LTC1771 W U TYPICAL PERFOR A CE CHARACTERISTICS Load Regulation 0.4 FIGURE 1 CIRCUIT 0.2 Burst Mode OPERATION DISABLED 15V IN –0.2 Burst Mode OPERATION –0.4 ENABLED –0.6 –0.8 –1.0 0 0.5 1.0 ...
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CTIO S RUN/SS (Pin 1): The voltage level on this pin controls shutdown/run mode (ground = shutdown, open/high = run). Connecting an external capacitor to this pin provides soft-start. I (Pin 2): Error Amplifier Compensation ...
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LTC1771 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 ...
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U U 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 Once R ...
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LTC1771 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 ...
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... Manufacturers such as Nichicon, United Chemicon and Sanyo should be considered for high performance through- hole capacitors. The OS-CON semiconductor dielectric capacitor available from Sanyo has the lowest ESR for its OPTI-LOOP is a trademark of Linear Technology Corporation size of any aluminum electrolytic at a somewhat higher price ...
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LTC1771 U U APPLICATIO S I FOR ATIO continuous mode GATECHG charge of the internal switch. Both the DC bias and gate charge losses are proportional to V effects will be more pronounced at higher supply voltages. ...
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U U APPLICATIO S I FOR ATIO limiting should be added to reduce the current in propor- tion to the severity of the fault. Foldback current limiting is implemented by adding two diodes in series between the output and the ...
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LTC1771 U U APPLICATIO S I FOR ATIO 2. Is the 0.1 F input decoupling capacitor closely con- nected between V (Pin 6) and ground (Pin 4)? This IN capacitor carries the high frequency peak currents. 3. Does the V ...
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U U APPLICATIO S I FOR ATIO With a 0.05 sense resistor I SC(AVG) increasing the 0.5V Schottky diode dissipation to 1W chosen for a RMS current rating of at least temperature chosen ...
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LTC1771 U TYPICAL APPLICATIO S 0.01 F 330pF 10k TAIYO YUDEN LMK550BJ476MM SANYO POSCAP 4TPB220M OUT D1: MICROSEMI UPS5817 L1: SUMIDA CR75-150 V IN 3.01M 220pF 1% Q1 280k 1% 402k 1% C ...
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... FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE 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. ...
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... LTC1174 with Internal Schottky Diode Constant Frequency 10V V 95% DC, 3.5V to 36V Quiescent Current Quiescent Current SOT-23, 2. 550kHz, MS8 10V 600mA OUT 550kHz, MS8 6V 600mA OUT 1771f LT/TP 1000 4K • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 2000 , MS8 IN Noise RMS Noise RMS = ...