ltc3773euhf-trpbf Linear Technology Corporation, ltc3773euhf-trpbf Datasheet
ltc3773euhf-trpbf
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ltc3773euhf-trpbf Summary of contents
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... LT, LTC, LTM, Burst Mode and OPTI-LOOP are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents including 5408150, 5481178, 5705919, 5929620, 6144194, 6177787, 6304066, 6498466, 6580258, 6611131. ...
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... TAPE AND REEL LTC3773EG#PBF LTC3773EG#TRPBF LTC3773EUHF#PBF LTC3773EUHF#TRPBF Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. Consult LTC Marketing for information on non-standard lead based fi nish parts. For more information on lead free part marking, go to: For more information on tape and reel specifi cations, go to: ...
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ELECTRICAL CHARACTERISTICS operating temperature range, otherwise specifi cations are at T SYMBOL PARAMETER Main Control Loop V Feedback Voltage FB I Feedback Pin Input Current VFB V Maximum Current Sense Threshold SENSEMAX V Feedback Voltage Load Regulation FBLOADREG V Feedback ...
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... T is calculated from the ambient J temperature T and power dissipation P according to the following A D formula. LTC3773EG 95°C/ LTC3773EUHF 34°C/ (Note 3) The denotes the specifi cations which apply over the full ● = 25° ...
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TYPICAL PERFORMANCE CHARACTERISTICS Effi ciency vs Load Current, Shutdown CH2 and CH3 100 CONTINUOUS 50 MODE 40 DISCONTINUOUS MODE 30 Burst Mode 20 OPERATION EFFICIENCY 10 POWER LOSS 0 0.001 0.01 0.1 1 CHANNEL 1 LOAD ...
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LTC3773 TYPICAL PERFORMANCE CHARACTERISTICS I and I vs Switching Frequency VDR VCC 120 V = 10V 5V FORCED CONTINUOUS MODE V = 2.5V WITH 5A LOAD 100 OUT1 V = 1.8V WITH 5A ...
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TYPICAL PERFORMANCE CHARACTERISTICS V vs Temperature FB 606.0 604.5 603.0 601.5 600.0 598.5 597.0 595.5 594.0 –50 – TEMPERATURE (°C) Maximum Current Limit Threshold vs Temperature 84 V – SENSE 81 V – = 2.5V ...
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LTC3773 TYPICAL PERFORMANCE CHARACTERISTICS Maximum Current Limit Threshold TRACK 300 0 100 200 V (mV) FB Switching Frequency vs Temperature 650 600 ...
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TYPICAL PERFORMANCE CHARACTERISTICS V Undervoltage Reset Voltage CC vs Temperature 4.4 4.3 4.2 4.1 4.0 3.9 3.8 3.7 –50 – TEMPERATURE (°C) PGOOD Delay vs Temperature 180 170 160 150 140 130 120 110 100 –50 –25 ...
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LTC3773 PIN FUNCTIONS (G/UHF) + SENSE1 (Pin 1/Pin 34): The (+) Input to the Channel 1 Differential Current Comparator. The I controlled offsets between the SENSE1 pins in conjunction with R set the channel 1 current SENSE trip threshold. – ...
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PIN FUNCTIONS (G/UHF) PLLIN/FC (Pin 20/Pin 17): Synchronization Input to the Phase Detector and Forced Continuous Control Input. When fl oating, it sits around 1.6V, and the controller enters discontinuous mode operation at light load. Shorting this pin low or ...
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LTC3773 FUNCTIONAL DIAGRAM CLKOUT PHASEMD PGOOD CH3 PBAD 100 s CH2 PBAD DELAY CH1 PBAD + – + – 0.54V 0.66V OV 0.6225V – – TRACK 0. CH3 ...
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OPERATION (Refer to the Functional Diagram) Main Control Loop The LTC3773 uses a constant frequency, current mode step down architecture. During normal operation, each top MOSFET is turned on each cycle when the oscillator sets the RS latch, and turned ...
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LTC3773 OPERATION (Refer to the Functional Diagram Burst Mode switching regulator. Burst Mode op- eration clamps the minimum peak inductor current to approximately 20% of the current limit programmed the load current goes down, ...
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APPLICATIONS INFORMATION The basic application circuit is shown on the fi rst page of this data sheet. External component selection is driven by the load requirement, and normally begins with the selection of an inductance value based upon the desired ...
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LTC3773 APPLICATIONS INFORMATION mainly depends on the price vs size requirements and any radiated fi eld/EMI requirements. New designs for high cur- rent surface mount inductors are available from numerous manufacturers, including Coiltronics, Vishay, TDK, Pulse, Panasonic, Vitec, Coilcraft, Toko ...
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APPLICATIONS INFORMATION where δ is the temperature dependency the effective top driver resistance (approximately 2Ω and V is the drain potential and the GS MILLER IN change in drain potential in the ...
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LTC3773 APPLICATIONS INFORMATION This formula has a maximum value /2. This simple worst-case condition is com- RMS OUT monly used for design because even signifi cant deviations do not offer much relief. Note that capacitor ...
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APPLICATIONS INFORMATION age output current I equal to the peak value less half MAX the peak-to-peak ripple current, ΔI Allowing a margin for variations in the IC and external component values yields: 55mV = R SENSE I MAX The IC ...
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LTC3773 APPLICATIONS INFORMATION + – SENSE /SENSE Pins The common mode input range of the current compara- tor sense pins is from 0V to (1.1)V operation is guaranteed throughout this range allowing output voltage setting from 0.6V to 7.7V, depending ...
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APPLICATIONS INFORMATION An internal 1μA current source pull-up at the TRACK pin programs the output to take about 600ms/μF to reach its steady state value. The output voltage ramp down slew rate can be controlled by the external capacitor C ...
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LTC3773 APPLICATIONS INFORMATION add an extra tracking resistive divider. When the tracking resistive divider input is grounded, the pull-up current fl ow- ing through the network could produce a small unwanted offset at the TRACK pin, forcing the controller to ...
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APPLICATIONS INFORMATION MOSFET of controller locked to the rising edge of an external clock signal applied to the PLLIN/FC pin. The turn-on of controller 2’s/3’s external N-channel MOSFET and CLKOUT signal are controlled by the PHASEMD pin ...
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LTC3773 APPLICATIONS INFORMATION The LTC3773 can be confi gured to operate at any switch- ing frequency within the synchronization range. Figure 7 shows a simple circuit to achieve this. The resistive divider at the PLLFLTR pin programs the LTC3773 switching ...
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APPLICATIONS INFORMATION The I series R -C fi lter sets the dominant pole-zero loop compensation. The values can be modifi ed slightly to maximize transient response once the fi nal PC layout is done and the particular ...
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LTC3773 APPLICATIONS INFORMATION that the minimum on-time of 130ns is not violated. The minimum on-time occurs at maximum V V 1.8V OUT = = t ON(MIN 22V(220kHz) IN(MAX) The R resistor value can be calculated by using the ...
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APPLICATIONS INFORMATION nected between the (+) terminal small decoupling capacitor should be placed across this divider; as close as possible to the LTC3773 SGND pin and away from any high current or high frequency switching nodes. – ...
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LTC3773 APPLICATIONS INFORMATION BOLD LINES INDICATE HIGH SWITCHING CURRENTS. KEEP LINES TO A MINIMUM LENGTH. 28 SW1 L1 R SENSE1 C D1 OUT1 SW2 L2 R SENSE2 C D2 OUT2 SW3 L3 R ...
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APPLICATIONS INFORMATION POWER DOWN V OUT1 POWER DOWN V OUT2 OUT1 0.01μF 1 TRACK1 47. FB1 1500pF 15k 3 I TH1 100pF 4 SGND 5 1500pF 330pF I TH2 6 6.8k I TH3 7 ...
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LTC3773 PACKAGE DESCRIPTION 7.8 – 8.2 0.42 ±0.03 RECOMMENDED SOLDER PAD LAYOUT 5.00 – 5.60** (.197 – .221) 0.55 – 0.95 0.09 – 0.25 (.022 – .037) (.0035 – .010) NOTE: 1. CONTROLLING DIMENSION: MILLIMETERS MILLIMETERS 2. DIMENSIONS ARE IN ...
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... ALL DIMENSIONS ARE IN MILLIMETERS Information furnished by Linear Technology Corporation is believed to be accurate and reliable. How- ever, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights. UHF Package 38-Lead Plastic QFN (5mm × ...
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... Dual PolyPhase Voltage Mode Synchronous Step-Down Switching Regulator with Output Tracking LTC3827 Low I , Dual, 2-Phase Synchronous Step-Down Controller trademark of Linear Technology Corporation. PolyPhase is a registered trademark of Linear Technology Corporation. SENSE 32 Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● ...