lt3845ife-trpbf Linear Technology Corporation, lt3845ife-trpbf Datasheet

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... The LT3845 is available in a 16-lead thermally enhanced TSSOP package LTC and LTM are registered trademarks of Linear Technology Corporation. Burst Mode is a registered trademark 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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... TAPE AND REEL LT3845EFE#PBF LT3845EFE#TRPBF LT3845IFE#PBF LT3845IFE#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 temperature range, otherwise specifi cations are at T – + SENSE = SENSE = 10V, SGND = PGND = SW = SYNC = 0V, unless otherwise noted. PARAMETER V Operating Voltage Range (Note Minimum Start ...

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LT3845 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T – + SENSE = SENSE = 10V, SGND = PGND = SW = SYNC = 0V, unless otherwise noted. PARAMETER TG, BG Drive On Voltage (Note 7) TG, BG ...

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TYPICAL PERFORMANCE CHARACTERISTICS CC(LOAD) 8. 25°C A 8.00 7.95 7.90 7. (mA) CC(LOAD) 3845 G04 V UVLO Threshold (Rising Temperature 6.5 6.4 6.3 ...

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LT3845 TYPICAL PERFORMANCE CHARACTERISTICS Maximum Current Sense Threshold vs Temperature 106 104 102 100 100 125 –50 – TEMPERATURE (°C) 3845 G13 TYPICAL APPLICATION V (Pin 1): The V pin is the main ...

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PIN FUNCTIONS threshold, which limits the negative excursion of the pin voltage. Therefore, this pin cannot be pulled low with a low impedance source. If the V pin must be externally C manipulated through a 1kΩ series resistance. ...

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LT3845 BLOCK DIAGRAM 8 3845fc ...

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APPLICATIONS INFORMATION Overview The LT3845 is a high input voltage range step-down synchronous DC/DC converter controller IC that uses a programmable constant frequency, current mode archi- tecture with external N-channel MOSFET switches. The LT3845 has provisions for high effi ciency, ...

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LT3845 APPLICATIONS INFORMATION where Q is the total MOSFET gate charge of the G(TOTAL) TG and BG. In applications where these conditions are exceeded, V must be derived from an external source after start-up. Maximum continuous regulator power dissipation may ...

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APPLICATIONS INFORMATION V pin, giving a total V current of 120μA. Burst current IN IN can be reduced further when V is driven using an output CC derived source, as the V component then reduced by the ...

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LT3845 APPLICATIONS INFORMATION at start-up the soft-start circuit will discharge the V voltage below the DC control voltage equivalent to zero inductor current. This will reduce the input supply inrush current. The soft-start circuit is disabled once the C voltage ...

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APPLICATIONS INFORMATION has a maximum voltage threshold of, typically, 100mV. Therefore, the peak inductor current is 100mV/R The maximum output load current, I inductor current minus half the peak-to-peak ripple cur- rent, Δ Allowing adequate margin for ripple ...

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LT3845 APPLICATIONS INFORMATION will increase the peak currents, requiring more fi ltering on the input and output of the supply. If ΔI the slope compensation circuit is ineffective and current mode instability may occur at duty cycles greater than 50%. ...

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APPLICATIONS INFORMATION Choose the MOSFET V specifi cation to exceed the DSS maximum voltage across the drain to the source of the MOSFET, which is V plus any additional ringing IN(MAX) on the switch node. Ringing on the switch node ...

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LT3845 APPLICATIONS INFORMATION The maximum ESR required to meet a ΔV requirement can be calculated by: (ΔV )(L)(f OUT SW ESR(MAX) = ⎛ V OUT V • 1– ⎜ OUT V ⎝ IN(MAX) Worst-case ΔV occurs at highest input voltage. ...

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APPLICATIONS INFORMATION If low supply current in standby mode is required, select a higher value The supply turn off voltage is 9% below turn on. In the example the V would be 13.2V. SUPPLY(OFF) If additional ...

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LT3845 APPLICATIONS INFORMATION FET carry PGND currents. SGND originates at the negative terminal of the V bypass capacitor, and is the small OUT signal reference for the LT3845. Don’t be tempted to run small traces to separate ground paths. A ...

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APPLICATIONS INFORMATION Locate the feedback resistors in close proximity to the LT3845 to minimize the length of the high impedance V node. FB – + The SENSE and SENSE traces should be routed together and kept as short as possible. ...

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LT3845 TYPICAL APPLICATIONS 9V-16V to 3.3V at 10A DC/DC Converter Capable of Withstanding 60V Transients 16V C 60V TRANSIENTS IN C IN2 2.2μF 0.1μF 100V R3 100V ×4 1.1M C3 8200pF R1 10k SYNC R2 R4 ...

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TYPICAL APPLICATIONS 9V-16V 10A DC/DC Converter, 500kHz Frequency Operation, Capable of Withstanding 36V Transients, All Ceramic Capacitors, Soft-Start and Burst Mode Enabled 16V C IN 36V TRANSIENTS C IN2 6.8μF 0.1μF 50V R3 ...

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LT3845 TYPICAL APPLICATIONS 9V-24V to 3.3V, 2-Phase at 10A per Phase, DC/DC Converter with Spread Spectrum Operation V IN 24V C IN 6.8μF 50V 1.21M ×2 1.21M R12 25k C11 + V OUT1 SYNC1 0.1μF ...

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... DIMENSIONS ARE IN 3. 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 16-Lead Plastic TSSOP (4 ...

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... High Voltage Current Mode Switching Regulator Controllers LT3800 High Voltage Synchronous Regulator Controller LT3844 High Voltage Current Mode Controller with Programmable Operating Frequency trademark of Linear Technology Corporation. SENSE Linear Technology Corporation 24 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● ...