lt3580ems8e-trpbf Linear Technology Corporation, lt3580ems8e-trpbf Datasheet

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... Additional features such as frequency foldback and soft- start are integrated. The LT3580 is available in tiny 3mm × 3mm 8-lead DFN and 8-lead MSOP packages. L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. V ...

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... LT3580EDD#PBF LT3580EDD#TRPBF LT3580IDD#PBF LT3580IDD#TRPBF LT3580EMS8E#PBF LT3580EMS8E#TRPBF LT3580IMS8E#PBF LT3580IMS8E#TRPBF Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. *The temperature grade is identifi label on the shipping container. Consult LTC Marketing for information on non-standard lead based fi nish parts. ...

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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T PARAMETER Operating Voltage Range Positive Feedback Voltage Negative Feedback Voltage Positive FB Pin Bias Current Negative FB Pin Bias Current Error Amplifi er Transconductance Error Amplifi er Voltage Gain Quiescent ...

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LT3580 TYPICAL PERFORMANCE CHARACTERISTICS Switch Current Limit at 1MHz 2.5 2.0 1.5 1.0 0 DUTY CYCLE (%) 3580 G01 Switch Current Limit at Minimum Duty Cycle 3.0 2.5 2.0 1.5 1.0 ...

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TYPICAL PERFORMANCE CHARACTERISTICS SHDN Pin Current –50°C 5 100°C 20° 0.5 1 1.5 SHDN VOLTAGE (V) 3580 G10 PIN FUNCTIONS FB (Pin 1): Positive and Negative Feedback Pin. For a boost or inverting ...

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LT3580 BLOCK DIAGRAM SHDN – 5 DISCHARGE + 1.3V DETECT UVLO SR2 1.215V 3 REFERENCE + 14.6k A1 – 14.6k A2 – ...

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OPERATION The LT3580 uses a constant-frequency, current mode con- trol scheme to provide excellent line and load regulation. Refer to the Block Diagram which shows the LT3580 in a boost confi guration. At the start of each oscillator cycle, the ...

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LT3580 OPERATION Start-Up Operation Several functions are provided to enable a very clean start-up for the LT3580. • First, the SHDN pin voltage is monitored by an internal voltage reference to give a precise turn-on voltage level. An external resistor ...

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APPLICATIONS INFORMATION Setting Output Voltage The output voltage is set by connecting a resistor (R from V to the FB pin determined from the fol- OUT FB lowing equation OUT ...

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LT3580 APPLICATIONS INFORMATION for boost, coupled inductor SEPIC and coupled inductor inverting topologies, or: DC • > • I OUT OUT 2(f) I LIM V • IN for the uncoupled inductor SEPIC and uncoupled inductor ...

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APPLICATIONS INFORMATION and temperature ranges. A 4.7μF to 20μF output capaci- tor is suffi cient for most applications, but systems with very low output currents may need only a 1μF or 2.2μF output capacitor. Always use a capacitor with a ...

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LT3580 APPLICATIONS INFORMATION Compensation—Theory Like all other current mode switching regulators, the LT3580 needs to be compensated for stable and effi cient operation. Two feedback loops are used in the LT3580— a fast current loop which does not require compensation, ...

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APPLICATIONS INFORMATION Using the circuit in Figure example, Table 3 shows the parameters used to generate the bode plot shown in Figure 5. Table 3. Bode Plot Parameters PARAMETER VALUE UNITS R 21.8 Ω ...

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LT3580 APPLICATIONS INFORMATION (1) SYNC may not toggle outside the frequency range of 200kHz to 2.5MHz unless it is stopped low to enable the free-running oscillator. (2) The SYNC frequency can always be higher than the free-running oscillator frequency, f ...

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APPLICATIONS INFORMATION 1.3V R UVLO1 SHDN 11.6μA R UVLO2 AT 1.3V (OPTIONAL) GND Figure 7. Confi gurable UVLO the regulator from operating at source voltages where these problems might occur. The shutdown pin comparator has voltage ...

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LT3580 APPLICATIONS INFORMATION tion, so they should not be used for calculating effi ciency in discontinuous mode or at light load currents. = Average Switch Current (DC)(I Switch I R Loss 13n(I Base ...

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APPLICATIONS INFORMATION Board layout also has a signifi cant effect on thermal re- sistance. The exposed package ground pad is the copper plate that runs under the LT3580 die. This is a good thermal path for heat out of the ...

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LT3580 APPLICATIONS INFORMATION GND OUT Figure 9. Suggested Component Placement for Boost Topology (Both DFN and MSOP Packages. Not to Scale). Pin 9 (Exposed Pad) must be soldered ...

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APPLICATIONS INFORMATION Figure 12. Switch-On Phase of an Inverting Converter. L1 and L2 Have Positive dI/dt Figure 13. Switch-Off Phase of an Inverting Converter. L1 and L2 Currents ...

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LT3580 TYPICAL APPLICATIONS Wide Input Range SEPIC Converter with 5V Output Switches at 2.5MHz V IN 2.6V TO 12V OPERATING 12V TO 32V TRANSIENT C1 2.2μF C1: 2.2μF , 35V, X5R, 1206 C2: 10μF , 10V, X5R, ...

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TYPICAL APPLICATIONS VFD (Vacuum Flourescent Display) Power Supply Switches at 2MHz to Avoid AM Band Danger High Voltage! Operation by High Voltage Trained Personnel Only 16V C1, C2: 4.7μF , 25V, X5R, 1206 C3-C7: 1μF , ...

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LT3580 TYPICAL APPLICATIONS High Voltage Positive Power Supply Uses Tiny 5.8mm × 5.8mm × 3mm Transformer and Switches at 200kHz Danger High Voltage! Operation by High Voltage Trained Personnel Only 2.2μF C1: 2.2μF , ...

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TYPICAL APPLICATIONS High Voltage Negative Power Supply Uses Tiny 5.8mm × 5.8mm × 3mm Transformer and Switches at 200kHz Danger High Voltage! Operation by High Voltage Trained Personnel Only SHDN RT SYNC C1 ...

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LT3580 TYPICAL APPLICATIONS 5V to 12V Boost Converter Switches at 2.5MHz and Uses a Tiny 4mm × 4mm × 1.7mm Inductor Transient Response with 400mA to 500mA to 400mA Output Load Step V OUT 0.5V/DIV AC COUPLED ...

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TYPICAL APPLICATIONS –5V Output Inverting Converter Switches at 2.5MHz and Accepts Inputs Between 3.3V to 12V V IN 3.3V TO 12V 1μF 4.7μH 4.7μ SHDN GND 60.2k LT3580 SYNC SS ...

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LT3580 PACKAGE DESCRIPTION 3.5 ±0.05 1.65 ±0.05 2.15 ±0.05 (2 SIDES) 0.25 ± 0.05 RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS PIN 1 TOP MARK (NOTE Package 8-Lead Plastic DFN (3mm × 3mm) (Reference LTC DWG # 05-08-1698) ...

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... LEAD COPLANARITY (BOTTOM OF LEADS AFTER FORMING) SHALL BE 0.102mm (.004") MAX 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. ...

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... High Effi ciency Step-Up DC/DC Converter SW LT3477 42V, 3A, 3.5MHz Boost, Buck-Boost, Buck LED Driver LT3479 3A Full-Featured DC/DC Converter with Soft-Start and Inrush Current Protection ThinSOT is a trademark of Linear Technology Corporation. 28 Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● ...