LTC3701EGN#TR Linear Technology, LTC3701EGN#TR Datasheet
LTC3701EGN#TR
Specifications of LTC3701EGN#TR
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LTC3701EGN#TR Summary of contents
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... Small 16-Lead Narrow SSOP Package U APPLICATIO S One or Two Lithium-Ion Powered Applications Notebook and Handheld Computers Personal Digital Assistants Portable Instruments Distributed DC Power Systems , LTC and LT are registered trademarks of Linear Technology Corporation. Burst Mode is a registered trademark of Linear Technology Corporation. U TYPICAL APPLICATIO 169k 1 – + ...
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LTC3701 ABSOLUTE AXI U RATI GS (Note 1) Input Supply Voltage (V )........................ – 0.3V to 10V IN – – SENSE1 , SENSE2 , PGATE1, PGATE2 PLLLPF, SENSE1 , SENSE2 , EXTCLK/MODE Voltages .............. – ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are T PARAMETER Oscillator and Phase-Locked Loop Oscillator Frequency Phase Detector Output Current Sinking Sourcing PGOOD Output PGOOD Voltage Low PGOOD Trip Level Note 1: Absolute Maximum Ratings are those values beyond which the ...
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LTC3701 W U TYPICAL PERFOR A CE CHARACTERISTICS Undervoltage Lockout Trip Voltage (Falling) vs Temperature 2.15 2.10 2.05 2.00 1.95 1.90 1.85 –60 –40 – 100 TEMPERATURE ( C) 3701 G04 Input and Shutdown Currents ...
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CTIO S – – SENSE1 , SENSE2 (Pins 1, 8): The (–) Inputs to the Differential Current Comparators. I /RUN1, I /RUN2 (Pins 2, 6): These pins each serve TH TH two functions. Each pin ...
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LTC3701 CTIO AL DIAGRA SENSE1 VOLTAGE V REF REFERENCE 0.8V UV UNDERVOLTAGE LOCKOUT SHDN1 SHDN2 BURST DEFEAT BURSTDIS EXTCLK/MODE 10 PHASE CLOCK DETECT DETECTOR 10k PLLLPF 7 CLK1 R C ...
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U OPERATIO (Refer to Functional Diagram) Main Control Loop The LTC3701 uses a constant frequency, current mode architecture with the two controller channels operating 180 degrees out of phase. During normal operation, each external P-channel power MOSFET is turned on ...
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LTC3701 U OPERATIO (Refer to Functional Diagram) Dropout Operation When the input supply voltage decreases towards the output voltage, the rate of change of the inductor current during the ON cycle decreases. This reduction means that the external P-channel MOSFET ...
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U OPERATIO (Refer to Functional Diagram) Why the need for 2-phase operation? Until recently, con- stant frequency dual switching regulators operated both channels in phase (i.e., single phase operation). This means that both topside MOSFETs are turned on at the ...
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LTC3701 U U APPLICATIO S I FOR ATIO The basic LTC3701 application circuit is shown in Fig- ure 1. External component selection is driven by the load requirement and begins with the selection of L and R Next, the power ...
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U U APPLICATIO S I FOR ATIO size for a fixed inductor value, but is very dependent on the inductance selected. As inductance increases, core losses go down. Unfortunately, increased inductance requires more turns of wire and therefore copper losses ...
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LTC3701 U U APPLICATIO S I FOR ATIO C and C Selection IN OUT The selection simplified by the 2-phase architec- IN ture and its impact on the worst-case RMS current drawn through the input network (battery/fuse/capacitor). ...
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U U APPLICATIO S I FOR ATIO error amplifier. The regulated output voltage is deter- mined by • 1 OUT R 1 For most applications, an 80k resistor is suggested for R1. To ...
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LTC3701 U U APPLICATIO S I FOR ATIO internal oscillator frequency may be set by applying a DC voltage to the PLLLPF pin. 550kHz operation can be selected by floating the PLLLPF pin. The PLLLPF pin may be connected to ...
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U U APPLICATIO S I FOR ATIO Checking Transient Response The regulator loop response can be checked by looking at the load transient response. Switching regulators take several cycles to respond to a step in load current. When a load ...
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LTC3701 U U APPLICATIO S I FOR ATIO 2) Are the signal and power grounds kept separate? The LTC3701 signal ground consists of the feedback resistor divider, the I /RUN compensation network, and Pin 4. TH The power ground consists ...
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U U APPLICATIO S I FOR ATIO BOLD LINES INDICATE HIGH, SWITCHING CURRENT LINES. KEEP LINES TO A MINIMUM LENGTH – + SENSE1 SENSE1 /RUN1 ...
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LTC3701 U TYPICAL APPLICATIO S 2-Phase, Synchronizable Dual Output Step-Down DC/DC Converter R7 169k R6 78.7k R8 80k R9 100k Optional Output Sequencing Circuit V IN 0.01 F 15k 1N4148 LT1004-1 1 1.2V LT1797 4 – V ...
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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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... Synchronous Step-Down DC/DC Converter OUT LTC3700 Constant Frequency Step-Down Controller with LDO Regulator LTC3728/LTC3728L Dual, 550kHz, 2-Phase Synchronous Step-Down Switching Regulator PolyPhase and No R 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 – ...