LTC3809EMSE-1 Linear Technology, LTC3809EMSE-1 Datasheet

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... The LTC3809-1 is available in tiny footprint thermally enhanced DFN and 10-lead MSOP packages. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. Burst is a registered trademark of Linear Technology Corporation Linear Technology Corporation. All other trademarks are the property of their respective owners ...

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... LTC3809EDD-1 LTC3809EDD-1#TR LTC3809IDD-1 LTC3809IDD-1#TR LTC3809EMSE-1 LTC3809EMSE-1#TR LTC3809IMSE-1 LTC3809IMSE-1#TR Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. *The temperature grade is identifi label on the shipping container. 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 PARAMETER Main Control Loops Input DC Supply Current Normal Operation Sleep Mode Shutdown UVLO Undervoltage Lockout Threshold (UVLO) Shutdown Threshold of RUN Pin Start-Up Current Source Regulated Feedback Voltage Output ...

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LTC3809-1 TYPICAL PERFORMANCE CHARACTERISTICS Effi ciency vs Load Current 100 FIGURE 8 CIRCUIT V = 2.5V OUT 3.3V OUT 1.2V OUT 1.8V OUT MODE = V IN ...

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TYPICAL PERFORMANCE CHARACTERISTICS Start-Up with Coincident Tracking ( 0s) OUT V x 2.5V V OUT 1.8V 500mV/DIV 38091 G09 10ms/DIV 590 1.18k TB FIGURE 8 CIRCUIT Regulated Feedback ...

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LTC3809-1 TYPICAL PERFORMANCE CHARACTERISTICS Oscillator Frequency vs Temperature –2 –4 –6 –8 –10 –60 –40 – TEMPERATURE (°C) 38091 G17 Sleep Current vs Input Voltage 130 120 110 100 ...

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PIN FUNCTIONS MODE (Pin 1): This pin performs two functions: 1) auxiliary winding feedback input, and 2) Burst Mode operation, pulse skipping or forced continuous mode select. To select Burst Mode operation at light loads, tie this pin to V ...

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LTC3809-1 FUNCTIONAL DIAGRAM VOLTAGE V REF SLOPE REFERENCE 0.6V UNDERVOLTAGE + SENSE LOCKOUT UVSD 0.7μA RUN 0.74ms INTERNAL SOFT-START GND 11 1μA MUX TRK/SS TRACK/SS 2 ...

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OPERATION (Refer to Functional Diagram) Main Control Loop The LTC3809-1 uses a constant frequency, current mode architecture. During normal operation, the top external P-channel power MOSFET is turned on when the clock sets the RS latch, and is turned off ...

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LTC3809-1 OPERATION (Refer to Functional Diagram) In sleep mode, much of the internal circuitry is turned off, reducing the quiescent current that the LTC3809-1 draws. The load current is supplied by the output capacitor. As the output voltage decreases, the ...

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OPERATION (Refer to Functional Diagram) Dropout Operation When the input supply voltage (V ) approaches the output IN voltage, the rate of change of the inductor current while the external P-channel MOSFET is on (ON cycle) decreases. This reduction means ...

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LTC3809-1 APPLICATIONS INFORMATION The typical LTC3809-1 application circuit is shown in Figure 8. External component selection for the controller is driven by the load requirement and begins with the selection of the inductor and the power MOSFETs. Power MOSFET Selection ...

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APPLICATIONS INFORMATION 2.0 1.5 1.0 0 –50 0 JUNCTION TEMPERATURE (°C) Figure Temperature DS(ON) The short-circuit current sense threshold ΔV approximately 90mV when IPRG is fl oating (60mV when IPRG is tied low; 150mV when ...

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LTC3809-1 APPLICATIONS INFORMATION that do not work well at high input voltages (e.g., V 5V) may work fi lower voltages (e.g., 3.3V). Selecting the N-channel MOSFET is typically easier, since for a given R , the gate charge ...

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APPLICATIONS INFORMATION Different core materials and shapes will change the size/ current and price/current relationship of an inductor. Toroid or shielded pot cores in ferrite or permalloy materials are small and don’t radiate much energy, but generally cost more than ...

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LTC3809-1 APPLICATIONS INFORMATION For most applications, a 59k resistor is suggested for R In applications where minimizing the quiescent current is critical, R should be made bigger to limit the feedback A divider current then results in very ...

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APPLICATIONS INFORMATION TIME (5b) Coincident Tracking Figure 5b and 5c. Two Different Modes of Output Voltage Tracking For coincident tracking ( OUT should always be ...

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LTC3809-1 APPLICATIONS INFORMATION The auxiliary output voltage V is normally set, as shown AUX in Figure 6, by the turns ratio N of the transformer • V AUX OUT V IN LTC3809-1 L1 1:N R6 ...

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APPLICATIONS INFORMATION If the duty cycle falls below what can be accommodated by the minimum on-time, the LTC3809-1 will begin to skip cycles (unless forced continuous mode is selected). The output voltage will continue to be regulated, but the ripple ...

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LTC3809-1 APPLICATIONS INFORMATION pulse of 20% to 100% of full load current having a rise time of 1μs to 10μs will produce output voltage and I pin waveforms that will give a sense of the overall loop stability. The gain ...

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TYPICAL APPLICATIONS ITH 220pF R ITH 15k 4 2 187k 3 59k 100pF L: VISHAY IHLP-2525CZ- SANYO 4TPB150MC OUT Figure 8. 550kHz, Synchronous DC/DC Converter with Internal Soft-Start 1 6 470pF 15k 4 10nF 2 ...

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LTC3809-1 TYPICAL APPLICATIONS 220pF 15k 1.18k Vx 590Ω 118k 100pF L: VISHAY IHLP-2525CZ- SANYO 4TPB150MC OUT V < Vx OUT PACKAGE DESCRIPTION 3.50 0.05 1.65 0.05 2.15 0.05 (2 SIDES) 0.25 0.05 0.50 BSC 2.38 0.05 (2 SIDES) ...

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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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... LTC3808 Low EMI, Synchronous Controller with Output Tracking 2.75V ≤ V SENSE LTC3809 Low EMI, Synchronous DC/DC Controller SENSE PolyPhase is a trademark of Linear Technology Corporation. Linear Technology Corporation 24 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● COMMENTS Burst Mode Operation, 16-Pin Narrow SSOP , Fault Protection, 3.5V ≤ ...