LTC3716EG Linear Technology, LTC3716EG Datasheet
LTC3716EG
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LTC3716EG Summary of contents
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... Internal Current Foldback and Short-Circuit Shutdown Overvoltage Soft Latch Eliminates Nuisance Trips Available in 36-Lead Narrow SSOP Package U APPLICATIO S Mobile Computer CPU Supply , LTC and LT are registered trademarks of Linear Technology Corporation. OPTI-LOOP and Burst Mode are trademarks of Linear Technology Corporation. U TYPICAL APPLICATIO 0.1 F FCB ...
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... IN Measured at FCB pin Measured at V EAIN V Ramping Down 1.2V, Sink/Source 5 A (Note 1.2V, (g • Ext Load) (Note ORDER PART TOP VIEW NUMBER 1 PGOOD 36 2 TG1 35 LTC3716EG 3 SW1 34 4 BOOST1 BG1 31 7 EXTV INTV PGND 28 10 BG2 27 11 ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER I Input DC Supply Current Q Normal Mode Shutdown I Soft-Start Charge Current RUN/SS V RUN/SS Pin ON Threshold RUN/SS V RUN/SS Pin Latchoff Arming RUN/SSLO I RUN/SS Discharge ...
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... Note calculated from the ambient temperature T J dissipation P according to the following formula: D LTC3716EG • Note 4: The LTC3716 is tested in a feedback loop that servos V specified voltage and measures the resultant V ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Efficiency vs Load Current (3 Operating Modes) (Figure 13) 100 Burst Mode 90 OPERATION 80 70 FORCED 60 CONTINUOUS MODE 50 CONSTANT 40 FREQUENCY 30 (BURST DISABLE ...
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LTC3716 W U TYPICAL PERFOR A CE CHARACTERISTICS Maximum Current Sense Threshold vs V (Soft-Start) RUN/ 1.6V SENSE(CM (V) RUN/SS 3716 G10 Load Regulation 0.0 FCB ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Load Step (Figure 13 15V 1.25V, SLEW RATE = 30A OUT V CC 50mV/DIV I CC 4A/DIV FCB = 0V 25 s/DIV 3716 G19 Current Sense Pin ...
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LTC3716 CTIO S RUN/SS (Pin 1): Combination of Soft-Start, Run Control Input and Short-Circuit Detection Timer. A capacitor to ground at this pin sets the ramp time to full current output. Forcing this pin below ...
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CTIO S V (Pin 32): Main Supply Pin. Should be closely de- IN coupled to the IC’s signal ground pin CTIO AL DIAGRA PLLIN f PHASE DET IN 50k PLLFLTR R LP ...
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LTC3716 U OPERATIO (Refer to Functional Diagram) Main Control Loop The LTC3716 uses a constant frequency, current mode step-down architecture with the two output stages oper- ating 180 degrees out of phase. During normal operation, each top MOSFET is turned ...
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U OPERATIO (Refer to Functional Diagram) Frequency Synchronization The phase-locked loop allows the internal oscillator to be synchronized to an external source via the PLLIN pin. The output of the phase detector at the PLLFLTR pin is also the DC ...
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... LTC3716 and external component values yields 2(50mV/I ) SENSE MAX PolyPhase is a registered trademark of Linear Technology Corporation. 12 vated when the output voltage falls below 70% of its nominal level whether or not the short-circuit latchoff circuit is enabled ...
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U U APPLICATIO S I FOR ATIO directly with frequency. In addition to this basic tradeoff, the effect of inductor value on ripple current and low current operation must also be considered. The PolyPhase approach reduces both input and output ...
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LTC3716 U U APPLICATIO S I FOR ATIO (see EXTV Pin Connection). Consequently, logic-level CC threshold MOSFETs must be used in most applications. The only exception is if low input voltage is expected (V < 5V); then, sublogic-level threshold MOSFETs ...
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U U APPLICATIO S I FOR ATIO much relief. Note that capacitor manufacturer’s ripple current ratings are often based on only 2000 hours of life. This makes it advisable to further derate the capacitor choose a capacitor rated ...
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LTC3716 U U APPLICATIO S I FOR ATIO INTV Regulator CC An internal P-channel low dropout regulator produces 5V at the INTV pin from the V supply pin. The INTV CC IN regulator powers the drivers and internal circuitry of ...
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U U APPLICATIO S I FOR ATIO OPTIONAL EXTV CC + CONNECTION V 5V < V < SEC 1N4148 TG1 LTC3716 N-CH EXTV CC SW1 R6 FCB BG1 N-CH R5 PGND Figure 5a. Secondary Output ...
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LTC3716 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 Fault Conditions: Overcurrent Latchoff The RUN/SS pin also provides the ability to latch off the controllers when an overcurrent condition is detected. The RUN/SS capacitor used initially to limit the ...
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LTC3716 U U APPLICATIO S I FOR ATIO If the external frequency ( greater than the oscil- PLLIN lator frequency f , current is sourced continuously, 0SC pulling up the PLLFLTR pin. When the external frequency is less ...
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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 0.18 A internal current source pulling the pin high. Include this ...
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LTC3716 U U APPLICATIO S I FOR ATIO 2) Transition losses apply only to the topside MOSFET(s), and are significant only when operating at high input voltages (typically 12V or greater). Transition losses can be estimated from ...
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U U APPLICATIO S I FOR ATIO loop and is the filtered and compensated control loop response. The gain of the loop will be increased by increasing R and the bandwidth of the loop will be C increased by decreasing ...
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LTC3716 U U APPLICATIO S I FOR ATIO 005 110 . MAIN 013 . 300 kHz 0 ...
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U U APPLICATIO S I FOR ATIO – Are the SENSE and SENSE leads routed together with minimum PC trace spacing? The filter capacitors between + – SENSE and SENSE pin pairs should be as close as possible ...
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LTC3716 U U APPLICATIO S I FOR ATIO of the input capacitor(s) with a short isolated PC trace since very high switched currents are present. A separate isolated path from the negative plate(s) of the input capacitor(s) should be used ...
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... Figure 13 20V Input, 0.6V to 1.75V/30A IMVPII Compatible Power Supply with Active Voltage Positioning 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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... High Efficiency Synchronous Step-Down Controller with 5-Bit VID TM LTC1778 No R Synchronous Current Mode Step-Down Controller SENSE Adaptive Power and No R are a trademarks of Linear Technology Corporation. SENSE Linear Technology Corporation 28 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 www.linear-tech.com U G Package 36-Lead Plastic SSOP (5 ...