LTC3700EMS Linear Technology, LTC3700EMS Datasheet
LTC3700EMS
Specifications of LTC3700EMS
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LTC3700EMS Summary of contents
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... Shutdown Mode Draws Only 10 A Supply Current Common Power Good Output for Both Supplies U APPLICATIO S Notebook Computers Portable Instruments One or Two Li-Ion Battery-Powered Applications , LTC and LT are registered trademarks of Linear Technology Corporation. Burst Mode is a registered trademark of Linear Technology Corporation. U TYPICAL APPLICATIO V IN1 5V ...
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... Sinking 5 A (Note /RUN Sourcing 5 A (Note 5) TH (Note 5) Measured 0. 3000pF LOAD C = 3000pF LOAD (Note INFORMATION ORDER PART NUMBER TOP VIEW LTC3700EMS 10 I /RUN – 8 SENSE PGATE MS PART MARKING MS PACKAGE = 150 C, = 230 C/ W LTXN JA MIN TYP MAX 210 340 200 ...
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ELECTRICAL CHARACTERISTICS range, otherwise specifications are PARAMETER LDO Regulator V Input Voltage IN2 Input DC Supply Current Normal Operation with Buck Enabled Normal Operation with Buck Undervoltage Shutdown with Buck Enabled Shutdown with Buck Undervoltage Regulated Feedback ...
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LTC3700 W U TYPICAL PERFOR A CE CHARACTERISTICS BUCK DC/DC CONTROLLER V Voltage vs Temperature FB 805 V = 4.2V IN 804 I /RUN = LOAD 803 802 801 800 799 798 797 796 795 –55 ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS LDO REGULATOR V Voltage vs Temperature FB2 850 V = 4.2V IN2 840 LDO = V FB2 830 I = 1mA 820 LOAD LOAD 810 800 790 780 I ...
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LTC3700 PIN FUNCTIONS V (Pin 1): LDO Input Supply Pin. Must be closely IN2 decoupled to GND (Pin 5). LDO (Pin 2): LDO Output Pin. Must be closely decoupled to GND (Pin 5) with a low ESR ...
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U U FUNCTIONAL DIAGRA – V SENSE 0.86V V 0.74V + – OSC FREQ FOLDBACK SHORT-CIRCUIT DETECT 0.3V – GND 5 W PGOOD PGOOD FB2 ICMP RS1 SLOPE R COMP ...
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LTC3700 U OPERATIO (Refer to Functional Diagram) Main Control Loop (Buck Controller) The LTC3700 is a constant frequency current mode switch- ing regulator. During normal operation, the external P-channel power MOSFET is turned on each cycle when the oscillator sets ...
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U OPERATIO (Refer to Functional Diagram) when the buck is operating below 40% duty cycle. How- ever, once the duty cycle exceeds 40%, slope com- pensation begins and effectively reduces the peak induc- tor current. The amount of reduction is ...
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LTC3700 U U APPLICATIONS INFORMATION The basic LTC3700 application circuit is shown in Figure 1. External component selection for the buck is driven by the load requirement and begins with the selection of L1 and R (= R1). Next, the ...
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U U APPLICATIONS INFORMATION In Burst Mode operation on the LTC3700, the ripple current is normally set such that the inductor current is continuous during the burst periods. Therefore, the peak- to-peak ripple current must not exceed ...
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LTC3700 U U APPLICATIONS INFORMATION In applications where the maximum duty cycle is less than 100% and the buck is in continuous mode, the R governed by OUT ...
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U U APPLICATIONS INFORMATION The selection driven by the required effective OUT series resistance (ESR). Typically, once the ESR require- ment is satisfied, the capacitance is adequate for filtering. The output ripple ( approximated ...
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LTC3700 U U APPLICATIONS INFORMATION Setting Output Voltage (Buck Controller) The buck develops a 0.8V reference voltage between the feedback (Pin 9) terminal and ground (see Figure 4). By selecting resistor R1, a constant current is caused to flow through ...
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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 represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. ...
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... Current Mode Synchronous Step-Down Controller SENSE LTC1872 ThinSOT Step-Up Controller LTC3404 1.4MHz Monolithic Synchronous Step-Down Controller LTC3406/LTC3406B 600mA (I ), 1.5MHz Synchronous Step-Down Converter OUT No R and ThinSOT are trademarks of Linear Technology Corporation. SENSE Linear Technology Corporation 16 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ...