LTC3734EUH#TRPBF Linear Technology, LTC3734EUH#TRPBF Datasheet

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... ESR values. The LTC3734 is available in a small 5mm × 5mm QFN package. For 2-phase applications refer to the LTC3735. , LTC and LT are registered trademarks of Linear Technology Corporation. OPTI-LOOP is a registered trademark of Linear Technology Corporation. MCH_PG TG M1 0.8μ ...

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LTC3734 ABSOLUTE AXI U RATI GS (Note 1) Input Supply Voltage ( ............. 7V to – 0. Topside Driver Voltages (BOOST) ..............38V to – 0.3V Switch Voltage (SW) ....................................32V to – 5V ...

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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER I Input DC Supply Current Q Normal Mode Shutdown UVR Undervoltage RUN/SS Reset I Soft-Start Charge Current RUN/SS V RUN/SS Pin ON Threshold RUN/SS V RUN/SS Pin Latchoff Arming ...

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LTC3734 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER Operational Amp I B Input Bias Current V OS Input Offset Voltage Magnitude CM Common Mode Input Voltage Range CMRR Common Mode Rejection Ratio I CL Output Source ...

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W U TYPICAL PERFOR A CE CHARACTERISTICS Supply Current vs SV Voltage CC and Mode 2500 ON 2000 1500 1000 500 SHUTDOWN VOLTAGE (V) CC 3734 G04 Maximum Current Sense Threshold vs V (Soft-Start) RUN/SS ...

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LTC3734 W U TYPICAL PERFOR A CE CHARACTERISTICS Maximum Current Sense Threshold vs Temperature –50 – 100 125 TEMPERATURE (°C) 3734 G13 Current Sense Pin Input Current vs Temperature –12 ...

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CTIO S + – (Pins 1, 2): Inputs to the Internal Operational OA OA Amplifier. OAOUT (Pin 3): Output of the Internal Operational Amplifier. STP_CPUB (Pin 4): Deep Sleep State Input. When ...

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LTC3734 CTIO S SW (Pin 23): Switch Node Connection to Inductor. Volt- age swing at this pin is from a Schottky diode (external) voltage drop below ground (Pin 24): High ...

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CTIO AL DIAGRA R3 MCH_PG FREQSET CLK OSCILLATOR STP_CPUB DPRSLPVR VID CHANGE PGOOD – 110μs BLANKING + RUN – – – OAOUT 3V 0.5μA PSIB + PSI ...

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LTC3734 U OPERATIO (Refer to Functional Diagram) Main Control Loop The LTC3734 uses a constant frequency, current mode step-down architecture. During normal operation, the top MOSFET is turned on when the clock sets the RS latch, and turned off when ...

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U OPERATIO (Refer to Functional Diagram) Operational Amplifier and Deep Sleep Offset The internal operational amplifier provides a program- mable output offset at deep sleep state (when the STP_CPUB signal is low). The offset percentage is pro- grammed by the ...

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LTC3734 U U APPLICATIO S I FOR ATIO The basic LTC3734 application circuit is shown in Figure 1 on the first page of this data sheet. External component selection begins with the selection of the inductors based on ripple current ...

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U U APPLICATIO S I FOR ATIO Inductor Core Selection Once the value for L1 is known, the type of inductor must be selected. High efficiency converters generally cannot afford the core loss found in low cost powdered iron cores, ...

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LTC3734 U U APPLICATIO S I FOR ATIO I 2 OUT = P V • • • SWTOP IN RSS 2 ⎛ ⎜ ⎝ V – MIN ( ) TH MIN ≈ ...

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U U APPLICATIO S I FOR ATIO required. Several capacitors may also be paralleled to meet size or height requirements in the design. Always consult the capacitor manufacturer if there is any question. The selection driven by ...

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LTC3734 U U APPLICATIO S I FOR ATIO VID Output Voltage Programming After 27μs ~ 71μs t delay, the output voltage of the BOOT regulator is digitally programmed as defined in Table 1 using the VID0 to VID5 logic input ...

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U U APPLICATIO S I FOR ATIO RUN/SS 1.5V V BOOT V OUT 90% V BOOT INTERNAL PG (OUTPUT OF INTERNAL POWER GOOD COMPARATOR) MCH_PG COMPOSITE PG (=(INTERNAL PG) AND (MCH_PG)) t BOOT MD INVALID VID BITS TIME Figure 4. ...

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LTC3734 U U APPLICATIO S I FOR ATIO Table 1. VID Output Voltage Programming VID5 VID4 VID3 VID2 VID1 ...

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U U APPLICATIO S I FOR ATIO enough period as determined by the size of the C controller will be shut down until the RUN/SS pin voltage is recycled. If the overload occurs during start-up, the time can be approximated ...

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LTC3734 U U APPLICATIO S I FOR ATIO where AVP is the slope the current sense resistor SENSE m is the number of phases for LTC3734 R3 and R are defined in Figure ...

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U U APPLICATIO S I FOR ATIO Efficiency varies as the inverse square of V same external components and output power level. The combined effects of increasingly lower output voltages and higher currents required by high performance digital systems is ...

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LTC3734 U U APPLICATIO S I FOR ATIO Automotive Considerations: Plugging into the Cigarette Lighter As battery-powered devices go mobile, there is a natural interest in plugging into the cigarette lighter in order to conserve or even recharge battery packs ...

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U U APPLICATIO S I FOR ATIO voltage with T (estimated) = 85° elevated ambient J temperature • • 005 85 . TOP 21 V ...

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LTC3734 U U APPLICATIO S I FOR ATIO PC Board Layout Checklist When laying out the printed circuit board, the following checklist should be used to ensure proper operation of the LTC3734. Check the following in your layout: 1) Are ...

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U TYPICAL APPLICATIO Figure 9 shows a typical application using the LTC3734 to power the mobile CPU core. The input can vary from 5V to 24V; the output voltage can be programmed from 0.7V to 1.708V with a maximum current ...

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LTC3734 U TYPICAL APPLICATIO 3.3V MCH_PG 2k DPRSLPVR PGOOD STP_CPUB 5V PSIB 1000pF 100k VID0 Si1034X VID1 VID2 VRON VID3 VID4 + V OA VID5 1M 1% 100pF 3k 1M 680pF 470pF 100pF V 1μF OUT X5R BAT54 5V 4.7μF ...

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... SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE TOP AND BOTTOM OF PACKAGE 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 Package 32-Lead Plastic QFN (5mm × ...

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... Synchronous Step-Down Controller LTC3731 3-Phase 600kHz Synchronous Step-Down Controller LTC3735 2-Phase DC/DC Controller for Pentium (Centrino) Processors trademark of Linear Technology Corporation. Pentium is a registered trademark of Intel Corporation. SENSE Linear Technology Corporation 28 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● ...