LTC1736IG Linear Technology, LTC1736IG Datasheet

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... Notebook and Palmtop Computers, PDAs Power Supply for Mobile Pentium Pentium III Processors Low Voltage Power Supplies , LTC and LT are registered trademarks of Linear Technology Corporation. OPTI-LOOP and Burst Mode are trademarks of Linear Technology Corporation. Pentium is a registered trademark of Intel Corporation. U TYPICAL APPLICATIO ...

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... 0.7V FB – 0.8V SENSE SENSE Tested with a Square Wave (Note 8) (Note 3300pF LOAD C = 3300pF LOAD U W ORDER PART TOP VIEW NUMBER BOOST LTC1736CG LTC1736IG INTV PGND 18 8 EXTV VIDV 16 CC VID4 15 VID3 14 VID2 13 G PACKAGE = 125 C, = 110 C unless otherwise noted. MIN ...

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... Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note calculated from the ambient temperature T J dissipation P according to the following formulas: D LTC1736CG, LTC1736IG • 110 C/ Note 3: The LTC1736 is tested in a feedback loop that servos V balance point for the error amplifier ( ...

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LTC1736 W U TYPICAL PERFOR A CE CHARACTERISTICS Efficiency vs Load Current (3 Operating Modes) 100 EXTV OPEN CC 90 BURST 80 SYNC 70 CONT 1.6V OUT 0.01 ...

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W U TYPICAL PERFOR A CE CHARACTERISTICS Maximum Current Sense Threshold vs Normalized Output Voltage (Foldback 100 NORMALIZED OUTPUT VOLTAGE (%) 1736 G10 Maximum Current Sense Threshold ...

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LTC1736 W U TYPICAL PERFOR A CE CHARACTERISTICS Oscillator Frequency vs Temperature 300 C = 47pF OSC 290 280 270 260 250 –40 – 135 110 TEMPERATURE ( C) 1736 G19 Start-Up V OUT 1V/DIV V ...

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CTIO S C (Pin 1): External capacitor C OSC ground sets the operating frequency. RUN/SS (Pin 2): Combination of Soft-Start and Run Control Inputs. A capacitor to ground at this pin sets the ramp time ...

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LTC1736 CTIO AL DIAGRA C 6 PGOOD C OSC – + 0.74V OV + – 0.86V V OSENSE 10k – 47pF + SGND 0.8V 5 VIDV ...

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U OPERATIO (Refer to Functional Diagram) The main control loop is shut down by pulling Pin 2 (RUN/ SS) low. Releasing RUN/SS allows an internal 1.2 A current source to charge soft-start capacitor C C reaches 1.5V, the main control ...

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LTC1736 U OPERATIO (Refer to Functional Diagram) INTV /EXTV Power CC CC Power for the top and bottom MOSFET drivers and most of the internal circuitry of the LTC1736 is derived from the INTV pin. When the EXTV pin is ...

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U U APPLICATIO S I FOR ATIO – 11 OSC Frequency A graph for selecting C versus frequency is given in OSC Figure 2. The maximum recommended switching fre- ...

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LTC1736 U U APPLICATIO S I FOR ATIO ® molypermalloy or Kool M cores. Actual core loss is independent of core size for a fixed inductor value, but it is very dependent on the inductance selected. As induc- tance increases, ...

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U U APPLICATIO S I FOR ATIO Larger diodes can result in additional transition losses due to their larger junction capacitance. The diode may be omitted if the efficiency loss can be tolerated. C Selection IN In continuous mode, the ...

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LTC1736 U U APPLICATIO S I FOR ATIO Manufacturers such as Nichicon, United Chemicon and Sanyo can be considered for high performance through- hole capacitors. The OS-CON semiconductor dielectric capacitor available from Sanyo has the lowest (ESR)(size) product of any ...

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U U APPLICATIO S I FOR ATIO regulator shuts off, the switch closes and INTV supplied via EXTV until EXTV drops below 4.5V. This CC CC allows the MOSFET gate drive and control power to be derived from the output ...

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LTC1736 U U APPLICATIO S I FOR ATIO Table 1. VID Output Voltage Programming VID4 VID3 VID2 VID1 ...

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U U APPLICATIO S I FOR ATIO Soft-Start/Run Function The RUN/SS pin is a multipurpose pin that provides a soft- start function and a means to shut down the LTC1736. Soft-start reduces surge currents from V increasing the controller’s current ...

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LTC1736 U U APPLICATIO S I FOR ATIO Why should you defeat overcurrent latchoff? During the prototyping stage of a design, there may be a problem with noise pickup or poor layout causing the protection circuit to latch off. Defeating ...

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U U APPLICATIO S I FOR ATIO Minimum On-Time Considerations Minimum on-time t is the smallest amount of time ON(MIN) that the LTC1736 is capable of turning the top MOSFET on and off again determined by internal timing ...

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LTC1736 U U APPLICATIO S I FOR ATIO In order to prevent erratic operation if no external connec- tions are made to the FCB pin, the FCB pin has a 0.17 A internal current source pulling the pin high. Remember ...

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U U APPLICATIO S I FOR ATIO 0.06 . This results in losses ranging from 3% to 17% as the output current increases from for a 1.8V output 20% for a 1.5V output. Efficiency ...

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... C11 2 18 PGND 4 10V C10 EXTV VIDV (OPTIONAL) VID4 14 VID3 13 VID2 D2: MOTOROLA MBRS340 L1: PANASONIC ETQP6F1R0SA M1 TO M3: FAIRCHILD FDS6680A R6: IRC LRF2512-01-R003-J U1: LINEAR TECHNOLOGY LTC1736CG V IN 7.5V TO 24V C12 TO C14 10 F 35V GND 0.003 V OUT 0. 15A + C15 TO C17 180 F/ MBRS340 C18 1 F GND ...

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U U APPLICATIO S I FOR ATIO accuracy is 1%, so the output transient voltage cannot exceed 0.097V 1.5V, the maximum output OUT voltage change controlled by the I TH Input Offset V • OUT V OSENSE ...

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LTC1736 U U APPLICATIO S I FOR ATIO To calculate the resistor values, first determine the ratio between them: V – INTVCC ITH NOM ( ) 085 ITH NOM ( ) V ...

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U U APPLICATIO S I FOR ATIO 50A I RATING 12V TRANSIENT VOLTAGE SUPPRESSOR GENERAL INSTRUMENT 1.5KA24A Figure 9. Plugging into the Cigarette Lighter Design Example As a design example, assume V = 12V(nominal 22V(max), ...

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LTC1736 U U APPLICATIO S I FOR ATIO 2. Does the V pin connect as close as possible to OSENSE the load? The optional 50pF to 100pF capacitor from V to SGND should be as close as possible to the ...

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... FLASH SHALL NOT EXCEED 0.254mm (0.010") 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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... Dual Output Synchronous Step-Down DC/DC Controller LTC1735 High Efficiency Synchronous Step-Down Controller, N-Ch Drive LTC1735-1 High Efficiency Step-Down Controller with Power Good Adaptive Power and No R are trademarks of Linear Technology Corporaton. SENSE Linear Technology Corporation 28 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 www.linear-tech.com ...