LTC3718EG Linear Technology, LTC3718EG Datasheet
LTC3718EG
Specifications of LTC3718EG
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LTC3718EG Summary of contents
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... LTC and LT are registered trademarks of Linear Technology Corporation. OPTI-LOOP is a registered trademark of Linear Technology Corporation trademark of Linear Technology Corporation. QDR RAMs and Quad Data Rate RAMs comprise a new family of products developed by Cypress Semiconductor, IDT and Micron Technology, Inc ...
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... RNG CC FB1 REF 50mV RNG FB1 REF 50mV RNG FB1 REF V = INTV , 50mV RNG CC FB1 REF RUN/SS Pin Rising U W ORDER PART TOP VIEW NUMBER 1 BOOST 24 LTC3718EG SW1 + 4 21 SENSE – SENSE 6 19 PGND1 INTV IN1 IN2 11 14 PGND2 ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are T SYMBOL PARAMETER V RUN Pin Latchoff Threshold RUN/SS(LT) I Soft-Start Charge Current RUN/SS(C) I Soft-Start Discharge Current RUN/SS( Undervoltage Lockout IN(UVLO) IN1 Driver Pull-Up On Resistance UP ...
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... LTC3718 ELECTRICAL CHARACTERISTICS 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 as follows: D LTC3718EG • 130 C/ TYPICAL PERFOR A CE CHARACTERISTICS Boost Converter Oscillator Frequency vs Temperature 2.00 ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Frequency vs Input Voltage 450 400 LOAD = 10A 350 300 250 LOAD = 0A 200 150 100 V = 1.25V OUT 50 FIGURE 1 CIRCUIT 0 1.5 1.7 1.9 2.1 INPUT VOLTAGE ...
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LTC3718 W U TYPICAL PERFOR A CE CHARACTERISTICS INTV Load Regulation CC 0 –0.1 –0.2 –0.3 –0.4 –0 INTV LOAD CURRENT (mA) CC 3718 G14 Undervoltage Lockout Threshold vs Temperature 4.0 3.5 3.0 2.5 2.0 ...
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CTIO S RUN/SS (Pin 1): Run Control and Soft-Start Input. A capacitor to ground at this pin sets the ramp time to full output current (approximately 3s/ F) and the time delay for overcurrent latchoff ...
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LTC3718 CTIO AL DIAGRA 0.7V 2.4V V VON t = (10pF ION 20k + I CMP – 1.4V V RNG 4 0.7V 5 240k ...
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U OPERATIO Main Control Loop The LTC3718 is a current mode controller for DC/DC step-down converters designed to operate from low input voltages. It incorporates a boost converter with a buck regulator. Buck Regulator Operation In normal operation, the top ...
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LTC3718 U U APPLICATIO S I FOR ATIO A typical LTC3718 application circuit is shown in Figure 1. External component selection is primarily de- termined by the maximum load current and begins with the selection of the sense resistance and ...
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U U APPLICATIO S I FOR ATIO 2.0 1.5 1.0 0.5 0 – JUNCTION TEMPERATURE ( C) Figure Temperature DS(ON) V OUT D TOP – OUT D BOT V ...
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LTC3718 U U APPLICATIO S I FOR ATIO R VON1 30k V OUT R VON2 100k (3a) Figure 3. Adjusting Frequency Shift with Load Current Changes filter out the I variations at the switching frequency. The ...
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U U APPLICATIO S I FOR ATIO transients. The output ripple V bounded by ESR OUT OUT Since I increases with input voltage, the output ripple is L highest at maximum input voltage. Typically, ...
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LTC3718 U U APPLICATIO S I FOR ATIO due to a dropping input voltage for example, then the output will drop out of regulation. The minimum input voltage to avoid dropout is OFF MIN ( ) V ...
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U U APPLICATIO S I FOR ATIO persists until the RUN/SS pin drops to 3.5V, then the con- troller turns off both power MOSFETs, shutting down the converter permanently. The RUN/SS pin must be actively pulled down to ground in ...
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LTC3718 U U APPLICATIO S I FOR ATIO losses. These arise from the resistances of the MOSFETs, inductor and PC board traces and cause the efficiency to drop at high output currents. In continuous mode ...
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U U APPLICATIO S I FOR ATIO and double check the assumed T in the MOSFET – 013 ...
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LTC3718 U U APPLICATIO S I FOR ATIO PC Board Layout Checklist When laying out a PC board follow one of the two suggested approaches. The simple PC board layout requires a dedicated ground plane layer. Also, for higher currents, ...
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... DIMENSIONS ARE IN 3. DRAWING NOT TO SCALE 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. One Half V ...
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... High Power DDR Memory Termination Regulator LTC3778 No R Synchronous Step-Down Controller SENSE LTC3831 High Power DDR Memory Termination Regulator No R and ThinSOT are trademarks of Linear Technology Corporation. SENSE Linear Technology Corporation 20 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 C SS ...