LTC3214 Linear Technology, LTC3214 Datasheet

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... Low external parts count (two flying capacitors, one programming resistor and two bypass capacitors at V the LTC3214 ideally suited for small, battery-powered applications. Built-in soft-start circuitry prevents excessive inrush cur- rent during start-up. High switching frequency enables the use of small external capacitors ...

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... SET 10-LEAD (3mm × 3mm) PLASTIC DFN EXPOSED PAD (PIN 11) IS GND, MUST BE SOLDERED TO PCB GND ORDER PART NUMBER LTC3214EDD Order Options Tape and Reel: Add #TR Lead Free: Add #PBF Lead Free Tape and Reel: Add #TRPBF Lead Free Part Marking: Consult LTC Marketing for parts specified with wider operating temperature ranges. ● ...

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... 2.2µ CONDITIONS I = 50µA SET Note 3: The LTC3214E is guaranteed to meet performance specifications from 0°C to 70°C. Specifications over the –40°C to 85°C ambient operating temperature range are assured by design, characterization and correlation with statistical process controls. I LED 600 500 ...

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... LTC3214 W U TYPICAL PERFOR A CE CHARACTERISTICS Input Shutdown Current vs Input Voltage 4 25°C A 3.0 2.5 2.0 1.5 1.0 0.5 0 2.9 3.1 3.3 3.5 3.7 INPUT VOLTAGE (V) Efficiency 100 100mA 200mA 90 300mA 80 70 50mA LED = AOT2015 2.9V TYP AT 100mA F 0 2.9 3.1 3.3 3.5 3.7 3.9 4.1 4.3 4.5 V (V) IN 3215 G08 1.5x Mode CPO Output Ripple V CPO ...

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... C2 to pulls this pin to GND when left floating. V (Pin 7): Power. Supply voltage for the LTC3214 should be bypassed with a 2.2µF to 4.7µF low impedance ceramic capacitor to GND. GND (Pin 9): Charge Pump Ground. This pin should be connected directly to a low impedance ground plane. ...

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... Charge Pump Strength SET When the LTC3214 operates in either the 1.5x mode or 2x mode, the charge pump can be modeled as a Thevenin (1) equivalent circuit to determine the amount of current available from the effective input voltage and effective ...

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... R1, changing the effective I Mode Switching The LTC3214 will automatically switch from 1x mode to 1.5x mode, and subsequently from 1.5x mode to 2x mode whenever the LED forward voltage approaches the maxi- mum CPO voltage for that mode. The part will wait approximately 2 ...

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... Both the style and value of the output capacitor can significantly affect the stability of the LTC3214. As shown in the Block Diagram, the LTC3214 uses a control loop to adjust the strength of the charge pump to match the current required at the output. The error signal of this loop is stored directly on the output charge storage capacitor ...

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... U pins can couple energy capacitively to adjacent PCB runs. Magnetic fields can also be generated if the flying capaci- tors are not close to the LTC3214 (i.e., the loop area is large). To decouple capacitive energy transfer, a Faraday shield may be used. This is a grounded PCB trace between the sensitive node and the LTC3214 pins. For a high quality AC ground, it should be returned to a solid ground plane that extends all the way to the LTC3214 ...

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... since the input current will be very close to the LED current. At moderate to high output power, the quiescent current of the LTC3214 is negligible and the expression above is valid. Once dropout is detected at the I LED enables the charge pump in 1.5x mode 1.5x boost mode, the efficiency is similar to that of a linear regulator with an effective input voltage of 1 ...

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... ALL DIMENSIONS ARE IN MILLIMETERS 4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE 5. EXPOSED PAD SHALL BE SOLDER PLATED 6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE TOP AND BOTTOM OF PACKAGE LTC3214 R = 0.115 0.38 ± 0.10 TYP 6 10 ...

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... McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● High Power Camera Light and Flash 2.2µF 2.2µF + – 2.9V TO 4.5V V CPO IN 2.2µF µP LTC3214 2.8V I LED EN 2.8V 41.2k I SET 1% 16.9k 1% 3214 TA02 COMMENTS V : 1.6V to 18V Package 25V ...