LTC3786EMSE#PBF Linear Technology, LTC3786EMSE#PBF Datasheet
LTC3786EMSE#PBF
Specifications of LTC3786EMSE#PBF
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LTC3786EMSE#PBF Summary of contents
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... The PLLIN/MODE pin selects among Burst Mode continuous inductor current mode at light loads. L, LT, LTC, LTM, Burst Mode, OPTI-LOOP , Linear Technology and the Linear logo are registered trademarks and No R trademarks are the property of their respective owners. Protected Patents, including 5408150, 5481178, 5705919, 5929620, 6177787, 6498466, 6580258, 6611131 ...
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... JMAX JA EXPOSED PAD (PIN 17) IS GND, MUST BE SOLDERED TO PCB ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL LTC3786EMSE#PBF LTC3786EMSE#TRPBF LTC3786IMSE#PBF LTC3786IMSE#TRPBF LTC3786EUD#PBF LTC3786EUD#TRPBF LTC3786IUD#PBF LTC3786IUD#TRPBF Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. ...
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ELECTRICAL CHARACTERISTICS junction temperature range, otherwise specifications are at T SYMBOL PARAMETER Main Control Loop VBIAS Chip Bias Voltage Operating Range V Regulated Feedback Voltage FB I Feedback Current FB V Reference Line Voltage Regulation REFLNREG V Output Voltage Load ...
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LTC3786 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER INTV Linear Regulator CC V Internal V Voltage INTVCC(VIN INT INTV Load Regulation LDO CC Oscillator and Phase-Locked Loop f Programmable Frequency PROG f Lowest Fixed ...
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TYPICAL PERFORMANCE CHARACTERISTICS Efficiency and Power Loss vs Output Current 100 CCM EFFICIENCY 30 CMM LOSS BURST EFFICIENCY 20 BURST LOSS PULSE-SKIPPING EFFICIENCY 10 PULSE-SKIPPING LOSS 0 0.01 0.1 OUTPUT CURRENT (A) Efficiency vs ...
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LTC3786 TYPICAL PERFORMANCE CHARACTERISTICS Regulated Feedback Voltage vs Temperature 1.212 1.209 1.206 1.203 1.200 1.197 1.194 1.191 1.188 –45 – 105 TEMPERATURE (°C) 3786 G09 Shutdown Current vs Input Voltage ...
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TYPICAL PERFORMANCE CHARACTERISTICS INTV vs Load Current CC 5. 12V IN 5.45 5.40 5.35 5.30 5.25 5.20 5. 100 120 140 160 LOAD CURRENT (mA) 3786 G18 Oscillator Frequency vs Input Voltage 360 ...
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LTC3786 TYPICAL PERFORMANCE CHARACTERISTICS Charge Pump Charging Current vs Operating Frequency 110 V = 16.5V BOOST 100 V = 12V 150 250 350 450 550 650 OPERATING FREQUENCY ...
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PIN FUNCTIONS (MSOP/QFN) FREQ (Pin 7/Pin 9): The Frequency Control Pin for the Internal VCO. Connecting the pin to GND forces the VCO to a fixed low frequency of 350kHz. Connecting the pin to INTV forces the VCO to a ...
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LTC3786 BLOCK DIAGRAM PGOOD + 1.32V – – 1.08V 20μA FREQ CLK VCO PFD PLLIN/ MODE SYNC DET 100k VBIAS SHDN 5.4V – LDO INTV GND SHDN + 0.425V SLEEP – – ...
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OPERATION (Refer to the Block Diagram) Main Control Loop The LTC3786 uses a constant-frequency, current mode step-up control architecture. During normal operation, the external bottom MOSFET is turned on when the clock sets the RS latch, and is turned off ...
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LTC3786 OPERATION (Refer to the Block Diagram) In sleep mode, much of the internal circuitry is turned off and the LTC3786 draws only 55μA of quiescent current. In sleep mode, the load current is supplied by the output capacitor. As ...
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OPERATION (Refer to the Block Diagram) The typical capture range of the LTC3786’s PLL is from approximately 55kHz to 1MHz, and is guaranteed to lock to an external clock source whose frequency is between 75kHz and 850kHz. The typical input ...
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LTC3786 APPLICATIONS INFORMATION The Typical Application on the first page is a basic LTC3786 application circuit. LTC3786 can be configured to use either inductor DCR (DC resistance) sensing or a discrete sense resistor (R ) for current sensing. The choice ...
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APPLICATIONS INFORMATION less half the peak-to-peak ripple current, ΔI the sense resistor value, use the equation: V SENSE(MAX SENSE Δ MAX 2 When using the controller in low V IN output applications, the maximum inductor ...
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LTC3786 APPLICATIONS INFORMATION Inductor Value Calculation The operating frequency and inductor selection are inter- related in that higher operating frequencies allow the use of smaller inductor and capacitor values. Why would anyone ever choose to operate at lower frequencies with ...
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APPLICATIONS INFORMATION which accounts for the loss caused by reverse recovery current, is inversely proportional to the gate drive current and has an empirical value of 1.7. 2 Both MOSFETs have I R losses while the bottom N-channel equation includes ...
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LTC3786 APPLICATIONS INFORMATION Soft-Start (SS Pin) The start-up of the V is controlled by the voltage on the OUT SS pin. When the voltage on the SS pin is less than the internal 1.2V reference, the LTC3786 regulates the VFB ...
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APPLICATIONS INFORMATION the INTV supply to collapse and effectively shut down CC the entire LTC3786 chip. Once the junction temperature drops back to approximately 155°C, the INTV back on. Long-term overstress (T J avoided as it can degrade the performance ...
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LTC3786 APPLICATIONS INFORMATION In forced continuous mode, if the duty cycle falls below what can be accommodated by the minimum on-time, the controller will begin to skip cycles but the output will continue to be regulated. More cycles will be ...
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APPLICATIONS INFORMATION The ITH series R -C filter sets the dominant pole-zero C C loop compensation. The values can be modified slightly to optimize transient response once the final PCB layout is complete and the particular output capacitor type and ...
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LTC3786 APPLICATIONS INFORMATION C is chosen to filter the square current in the output. OUT The maximum output current peak is: ⎛ RIPPLE • 1+ ⎜ OUT(PEAK) OUT(MAX) ⎝ ⎛ ⎞ 31 • 1+ ⎟ ...
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APPLICATIONS INFORMATION Reduce V from its nominal level to verify operation with IN high duty cycle. Check the operation of the undervoltage lockout circuit by further lowering V the outputs to verify operation. Investigate whether any problems exist only at ...
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LTC3786 APPLICATIONS INFORMATION C 0.1μ 15nF ITH R 8.66k ITH C 220pF ITHA R 12. 232k OUTB D: BAS140W L: PULSE PA1494.362NL MBOT, MTOP: RENESAS HAT2169H *WHEN V C 0.1μF ...
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APPLICATIONS INFORMATION C 0.1μ 15nF ITH R 8.66k ITH C 220pF ITHA R 12. 357k OUTB D: BAS170W L: PULSE PA2050.103NL MBOT, MTOP: RENESAS RJIC0652DPB *WHEN V C 0.1μ 100nF ITH ...
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LTC3786 APPLICATIONS INFORMATION 60.4k RUN f = 400kHz SW FREQ C SS 0.1μ ITH R ITH 10nF 4.64k ITH C ITHA 100pF R A 12.1k VFB R B 88. TDK C4532X5R1E226M IN OUTA C ...
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APPLICATIONS INFORMATION PLLIN/MODE RUN FREQ C SS 0.1μ ITH R ITH 6.8nF 5.11k ITH C ITHA 100pF R A 150k VFB R B 475k TDK C3225X5R1A476M IN OUT L: TOKO FDV0840-R67M MBOT, MTOP: INFINEON ...
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LTC3786 APPLICATIONS INFORMATION C SS 0.1μF C ITH R ITH 15nF 8.87k C ITHA 220pF R A 12. 232k C1: TDK C1005X7R1C104K OUTB L: PULSE PA2050.103NL MBOT, MTOP: RENESAS RJK0305 D: INFINEON BAS140W ...
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APPLICATIONS INFORMATION DANGER HIGH VOLTAGE! OPERATION BY HIGH VOLTAGE TRAINED PERSONNEL ONLY 25k f = 105kHz SW C ITH R 22nF 8.66k C ITHA 100pF 16. 22nF ITH R ITH C ITHA 12.1k 1% Figure 16. ...
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LTC3786 PACKAGE DESCRIPTION 2.845 0.102 (.112 .004) 5.23 (.206) MIN 0.305 0.038 (.0120 .0015) TYP RECOMMENDED SOLDER PAD LAYOUT DETAIL “A” 0.254 (.010) GAUGE PLANE DETAIL “A” 0.18 (.007) NOTE: 1. DIMENSIONS IN MILLIMETER/(INCH) 2. DRAWING NOT TO SCALE 3. ...
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... 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 representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. UD Package 16-Lead Plastic QFN (3mm × ...
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... OUT ≤ 38V 60V, 50kHz to 900kHz, 5mm × 5mm OUT ≤ 38V, Boost Output Voltage Up to 60V, 50kHz to 900kHz, ≤ 36V, Burst Mode IN ≤ 30V, SSOP-24, 5mm × 5mm QFN-32 OUT LT 1010 • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2010 3786f ...