LTC3829IFE#TRPBF Linear Technology, LTC3829IFE#TRPBF Datasheet
LTC3829IFE#TRPBF
Specifications of LTC3829IFE#TRPBF
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LTC3829IFE#TRPBF Summary of contents
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... The LTC3829 is available in both low profile 38-pin 5mm × 7mm QFN and Exposed Pad FE packages. L, LT, LTC, LTM, Burst Mode, OPTI-LOOP , PolyPhase, Linear Technology, the Linear logo are registered trademarks and Stage Shedding Corporation. All other trademarks are the property of their respective owners. Protected by U ...
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LTC3829 absoluTe MaxiMuM raTings Input Supply Voltage (V ) ......................... 40V to –0.3V IN Topside Driver Voltages (BOOSTn) ............ 46V to –0.3V Switch Voltage (SWn) ................................... 40V to –5V Boosted Driver Voltage (BOOSTn – SWn) .... 6V to –0.3V INTV ...
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... LTC3829EFE#PBF LTC3829EFE#TRPBF LTC3829IFE#PBF LTC3829IFE#TRPBF Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. Consult LTC Marketing for information on non-standard lead based finish parts. For more information on lead free part marking, go to: ...
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LTC3829 elecTrical characTerisTics junction temperature range, otherwise specifications are at T SYMBOL PARAMETER TG Transition Time TG1,2,3 t Rise Time r TG1,2,3 t Fall Time f BG Transition Time BG1,2,3 t Rise Time r BG1,2,3 t Fall Time f TG/BG ...
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T SYMBOL PARAMETER Nonlinear Fast Transit Mode I Fast Transient Programmable Current V FAST AVP (Active Voltage Positioning) I Sink Current of AVP Pin SINK I Source Current of AVP Pin ...
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LTC3829 Typical perForMance characTerisTics Load Step-Up (0A to 75A, 75A/µs) (Nonlinear Operation) V OUT 100mV/DIV AC-COUPLED 75mV V SW1 10V/DIV V SW2 10V/DIV V SW3 10V/DIV 2µs/DIV Phase Shedding Transition V SW1 10V/DIV V SW2 10V/DIV V SW3 10V/DIV V ...
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Typical perForMance characTerisTics Quiescent Current vs Input Voltage without EXTV CC 5.5 5.3 5.1 4.9 4.7 4.5 4.3 4.1 3.9 3.7 3 INPUT VOLTAGE (V) 3829 G08 Maximum Current Sense Threshold vs Common Mode Voltage 90 ...
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LTC3829 Typical perForMance characTerisTics Regulated Feedback Voltage vs Temperature 0.604 0.602 0.600 0.598 0.596 0.594 0.592 –50 – 100 TEMPERATAURE (°C) 3829 G16 Oscillator Frequency vs Input Voltage 800 V FREQ 600 V FREQ 400 V ...
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FuncTions (UHF/FE) DIFFN (Pin 1/Pin 3): Negative Input of Remote Sensing Differential Amplifier. Connect this to the remote load ground pin. DIFFP (Pin 2/Pin 4): Positive Input of Remote Sensing Differential Amplifier. Connect this to the remote load positive ...
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LTC3829 pin FuncTions (UHF/FE) BOOST1, BOOST2, BOOST3 (Pins 33, 26, 19/Pins 35, 28, 21): Boosted Floating Driver Supplies. The (+) terminal of the bootstrap capacitors connect to these pins. These pins swing from a diode voltage drop below INTV to ...
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FuncTional DiagraM MODE PLLIN FREQ MODE/SYNC DETECT PLL-SYNC CLKOUT OSC – REV COMP – + IFAST IFAST I LIM SLOPE COMPENSATION INTV UVLO CC 1 51k SLOPE RECOVERY I THB ACTIVE CLAMP SLEEP ...
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LTC3829 operaTion (Refer to Functional Diagram) Main Control Loop The LTC3829 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 off ...
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Functional Diagram) Light Load Current Operation (Burst Mode Operation, Stage Shedding or Continuous Conduction) The LTC3829 can be enabled to enter high efficiency Burst Mode operation, Stage Shedding mode or forced continuous conduction mode. To select forced ...
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LTC3829 operaTion (Refer to Functional Diagram) A phase-locked loop (PLL) is available on the LTC3829 to synchronize the internal oscillator to an external clock source that is connected to the PLLIN pin. The PLL loop filter network is integrated inside ...
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The Typical Application on the first page of this data sheet is a basic LTC3829 application circuit. The LTC3829 can be configured to use either DCR (inductor resistance) sens- ing or low value resistor sensing. The choice between ...
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LTC3829 applicaTions inForMaTion LTC3829 SGND OPTIONAL TEMP COMP NETWORK NTC peak sense voltage can be as low as 20mV. In addition, inductor ripple currents greater than 50% with operation up to 1MHz are becoming more ...
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V t • t ESL STEP ( ) ON OFF ESL = ∆ ...
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LTC3829 applicaTions inForMaTion A conservative value for T is 100°C. To scale the L(MAX) maximum inductor DCR to the desired sense resistor value, use the divider ratio: R SENSE EQUIV ( ) DCR MAX ...
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The NTC resistor has a negative temperature coefficient, meaning its value decreases as temperature rises. The V voltage, therefore, decreases as temperature in- ITEMP creases and in turn, the V SENSEMAX(ADJ) compensate the DCR temperature coefficient. The NTC ...
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LTC3829 applicaTions inForMaTion 10000 THERMISTOR RESISTANCE R = 100k O 1000 T = 25° 4334 FOR 25°C/100°C 100 R ITMP R = 20k 43. 100k NTC 1 –40 – ...
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Slope Compensation and Inductor Peak Current Slope compensation provides stability in constant frequen- cy current mode architectures by preventing sub-harmonic oscillation at high duty cycles accomplished internally by adding a compensating ramp to the inductor current ...
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LTC3829 applicaTions inForMaTion Power MOSFET and Schottky Diode (Optional) Selection At least two external power MOSFETs must be selected for each of the three output sections: One N-channel MOSFET for the top (main) switch and one or more N-channel MOSFET(s) ...
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N is the number of output stages, δ is the tem- perature dependency DS(ON) driver resistance (approximately 2Ω the drain potential and the change in drain potential in the particular ...
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LTC3829 applicaTions inForMaTion The Figure 10 graph shows that the peak RMS input current is reduced linearly, inversely proportional to the number N of stages used important to note that the efficiency loss is proportional to the input ...
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The emergence of very low ESR capacitors in small, surface mount packages makes very small physical implementa- tions possible. The ability to externally compensate the switching regulator loop using the I wider selection of output capacitor types. The ...
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LTC3829 applicaTions inForMaTion The final load slope is defined by the inductor current sense resistors and the two external resistors mentioned above. In summary, the load slope is: R AVP R • ...
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Nonlinear control is only enabled when V UV and OV window. It should be enabled only for forced continuous mode of operation. Once nonlinear control is enabled, the top gate of all chan- nels will turn on if: ...
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LTC3829 applicaTions inForMaTion The LTC3829 allows the user to program how its output ramps up and down by means of the TK/SS pins. Through these pins, the output can be set up to either coincidentally or ratiometrically track another supply’s ...
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INTV (LDO) and EXTV CC CC The LTC3829 features a true PMOS LDO that supplies power to INTV from the V supply. INTV CC IN drivers and much of the LTC3829’s internal circuitry. The LDO regulates the voltage ...
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LTC3829 applicaTions inForMaTion 4. EXTV connected to an output-derived boost network. CC For 3.3V and other low voltage regulators, efficiency gains can still be realized by connecting EXTV output-derived voltage that has been boosted to greater than 4.7V. For applications ...
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Fault Conditions: Current Limit and Current Foldback The LTC3829 includes current foldback to help limit load current when the output is shorted to ground. If the out- put falls below 50% of its nominal output level, then the ...
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LTC3829 applicaTions inForMaTion EXTERNAL OSCILLATOR Minimum On-Time Considerations Minimum on-time the smallest time duration ON(MIN) that the LTC3829 is capable of turning on the top MOSFET determined by internal timing delays and the gate charge ...
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Efficiency Considerations The percent efficiency of a switching regulator is equal to the output power divided by the input power times 100 often useful to analyze individual losses to determine what is limiting the efficiency and ...
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LTC3829 applicaTions inForMaTion Checking Transient Response The regulator loop response can be checked by looking at the load current transient response. Switching regulators take several cycles to respond to a step in DC (resistive) load current. When a load step ...
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Keep the SGND at one end of a printed circuit path thus preventing MOSFET currents from traveling under the IC. The INTV decoupling capacitor should be placed CC immediately adjacent to the IC between the INTV and ...
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LTC3829 applicaTions inForMaTion BOLD LINES INDICATE HIGH, SWITCHING CURRENTS. KEEP LINES TO A MINIMUM LENGTH SW1 R SENSE1 D1 L2 SW2 R SENSE2 D2 L3 SW3 R SENSE3 D3 Figure 17. ...
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Typical applicaTion IFAST RUN MODE FREQ ILIM PLLIN LTC3829 SENSE3 – SENSE3 + SENSE2 – SENSE2 + SENSE1 – SENSE1 + 3829f ...
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LTC3829 package DescripTion 5.50 0.05 4.10 0.05 3.00 REF APPLY SOLDER MASK TO AREAS THAT ARE NOT SOLDERED 5.00 0.10 PIN 1 TOP MARK (SEE NOTE 6) 7.00 0.10 NOTE: 1. DRAWING CONFORMS TO JEDEC PACKAGE OUTLINE M0-220 VARIATION WHKD ...
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... 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 representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. FE Package 38-Lead Plastic TSSOP (4.4mm) ...
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... MSOP-16E, 3mm × 3mm QFN-16 OUT IN = 43ns, 4V ≤ V ON(MIN) ≤ 0.9V , SSOP-16 OUT IN = 43ns, 4V ≤ V ON(MIN) , MSOP-16E, 3mm × 3mm QFN-16 ≤ 0.9V OUT IN LT 0410 • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 2010 ≤ 38V, IN ≤ 38V, IN 3829f ...