LTC3546IUFD#PBF Linear Technology, LTC3546IUFD#PBF Datasheet
LTC3546IUFD#PBF
Specifications of LTC3546IUFD#PBF
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LTC3546IUFD#PBF Summary of contents
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... In shut- down, the device draws <1μA. L, LT, LTC, LTM, Linear Technology, the Linear logo and Burst Mode are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents, including 5481178, 6611131, 6304066, 6498466, 6580258. ...
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... PLASTIC QFN T = 125°C, θ = 34°C/W JMAX JA EXPOSED PAD (PIN 29) IS GNDD ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL LTC3546EUFD#PBF LTC3546EUFD#TRPBF LTC3546IUFD#PBF LTC3546IUFD#TRPBF LTC3546EFE#PBF LTC3546EFE#TRPBF LTC3546IFE#PBF LTC3546IFE#TRPBF LEAD BASED FINISH TAPE AND REEL LTC3546EUFD LTC3546EUFD#TR LTC3546IUFD LTC3546IUFD#TR ...
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ELECTRICAL CHARACTERISTICS junction temperature range, otherwise specifi cations are at T SYMBOL PARAMETER Operating Voltage Range IN1 IN1D IN2, CCA V CCD Feedback Pin Input Current FB1 FB2 V , ...
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LTC3546 ELECTRICAL CHARACTERISTICS junction temperature range, otherwise specifi cations are at T SYMBOL PARAMETER I Switch Leakage Current SW1D SW1D(LKG) I Switch Leakage Current SW2A/B SW2A/B(LKG) V Undervoltage Lockout Threshold UVLO T Threshold for Power Good PGOOD1 Percentage Deviation from ...
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TYPICAL PERFORMANCE CHARACTERISTICS OUT1 Burst Mode Operation V OUT 20mV/DIV I LOAD 500mA/DIV 3546 G02 2μs/DIV SW1D CONNECTED TO SW1 1.8V OUT I = 300mA LOAD OUT1 Burst Mode Operation V OUT 20mV/DIV I ...
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LTC3546 TYPICAL PERFORMANCE CHARACTERISTICS OUT2 Burst Mode Operation V OUT 20mV/DIV I LOAD 500mA/DIV 3546 G11 1μs/DIV SW1D CONNECTED TO SW1 2.5V OUT I = 300mA LOAD OUT1 Effi ciency vs Load Current 95 ...
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TYPICAL PERFORMANCE CHARACTERISTICS OUT2 Effi ciency 100 600mA SW1D CONNECTED TO SW2 2.5V OUT 80 2.25 2.75 3.25 3.75 4.25 4.75 5.25 V (V) IN ...
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LTC3546 TYPICAL PERFORMANCE CHARACTERISTICS OUT2 Effi ciency vs Frequency SW1D CONNECTED TO SW1 3. 2.5V 86 OUT I = 400mA LOAD 85 0.5 1.0 1.5 2.0 ...
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PIN FUNCTIONS (UFD/FE) BMC2 (Pin 1/Pin 4): Burst Mode Clamp for Channel 2. Connect-ing this pin to an external voltage between 0V and 0.6V sets the Burst Mode clamp level. If this pin is pulled internal ...
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LTC3546 PIN FUNCTIONS (UFD/FE) V (Pin 20/Pin 23): Feedback voltage from external FB1 resistive divider from Channel 1 output. Nominal voltage for this pin is 0.6V. TRACK/SS1 (Pin 21/Pin 24): Tracking input for Channel 1 output or optional external soft-start ...
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FUNCTIONAL DIAGRAM V FB1 0.552V 0.63V RUN1 V CCA 1.15μA TRACK/SS1 VOLTAGE REFERENCE SYNC/MODE V CCA GNDA V CCD GNDD V CCA 1.15μA TRACK/SS2 RUN2 0.63V 0.552V V FB2 I BMC1 TH1 I LIMIT TH + – – ...
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LTC3546 OPERATION The LTC3546 uses a constant-frequency, current mode archi- tecture. Both channels share the same clock frequency. The PHASE pin sets whether the channels are running in-phase, or 180° out-of-phase. The operating frequency is determined by connecting the FREQ ...
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OPERATION The output capacitor and the inductor supply the power to the load until I exceeds 0.31V, turning on the switch TH and the main control loop which starts another cycle. The Burst Mode peak inductor current can be set ...
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LTC3546 APPLICATIONS INFORMATION A general LTC3546 application circuit is shown in Figure 7. External component selection is driven by the load require- ment, and begins with the selection of the inductors L1, and L2. Once L1 and L2 are chosen, ...
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APPLICATIONS INFORMATION Burst Mode Operation Considerations There are two factors that determine the load current at which the LTC3546 enters Burst Mode operation: the inductor value and the BMC pin voltage. The transition from low current operation begins when the ...
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LTC3546 APPLICATIONS INFORMATION the maximum RMS current. The RMS current calculation is different if the part is used in-phase or out-of-phase. For in-phase, there are two different equations: V > OUT1 OUT2 I = RMS ( 2 ( ...
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APPLICATIONS INFORMATION density, but it has a larger ESR and it is critical that the capacitors are surge tested for use in switching power supplies. An excellent choice is the AVX TPS series of surface tantalums, available in case heights ...
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LTC3546 APPLICATIONS INFORMATION Keeping the current small (<20μA) in these resistors maximizes effi ciency, but making the current too small may allow stray capacitance to cause noise problems and reduce the phase margin of the error amp loop. To improve ...
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APPLICATIONS INFORMATION The LTC3546 can also track an external voltage during startup by using an external voltage divider to the TRACK/SS pin, and also insuring that the ramp rate on the TRACK/SS pin is slower than the internal 1.2ms ramp ...
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LTC3546 APPLICATIONS INFORMATION tors. This mode provides the best low current effi ciency at the cost of a higher output voltage ripple. When SYNC/MODE is connected to ground, pulse-skipping operation is selected for both regulators. This mode provides a lower ...
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... APPLICATIONS INFORMATION overall supply performance. For a detailed explanation of optimizing the compensation components, including a review of control loop theory, refer to Linear Technology Application Note 76. Although a buck regulator is capable of providing the full output current in dropout, it should be noted that as the input voltage V drops toward V , the load step capability ...
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LTC3546 APPLICATIONS INFORMATION tion to exceed the maximum junction temperature of the part majority of applications, the LTC3546 does not dissipate much heat due to its high effi ciency. However, in applications where the LTC3546 is running at ...
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APPLICATIONS INFORMATION operating frequency of 1.5MHz and assumes roughly a 300mA/A load step. 22 µF 280 mA C • • = OUT 1 300 mA A • µF 875 mA C • . ...
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LTC3546 APPLICATIONS INFORMATION V IN 2.25V TO 5. 22μF V OUT2 1.8V FF2 100pF C OUT2 47μF R3 60.4k 30. 22μF, X5R R7 100k R8 100k V OUT2 2.5V/ 22μF, ...
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APPLICATIONS INFORMATION V IN 2.25V TO 5. 22μF V OUT2 2.5V FF2 100pF C OUT2 33μ 95.3k OUT1 Effi ciency (Burst Mode Operation) 100 95 EFFICIENCY POWER LOSS 75 70 0.001 ...
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... ON THE TOP AND BOTTOM OF PACKAGE 26 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. UFD Package 28-Lead Plastic QFN (4mm × ...
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PACKAGE DESCRIPTION 4.75 (.187) 6.60 ±0.10 4.50 ±0.10 SEE NOTE 4 RECOMMENDED SOLDER PAD LAYOUT 4.30 – 4.50* (.169 – .177) 0.09 – 0.20 0.50 – 0.75 (.0035 – .0079) (.020 – .030) NOTE: 1. CONTROLLING DIMENSION: MILLIMETERS 2. DIMENSIONS ...
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... Converter LTC3561 1.25A, 4MHz, Synchronous Step-Down DC/DC Converter 2 LTC3562 Quad Interface, 600mA/600mA/400mA/400mA , 2.25MHz Synchronous Step-Down DC/DC Converter ThinSOT is a trademark of Linear Technology Corporation. Linear Technology Corporation 28 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● COMMENTS 96% Effi ciency, V IN(MIN) ThinSOT™ ...