lt3486efe-trpbf Linear Technology Corporation, lt3486efe-trpbf Datasheet
lt3486efe-trpbf
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lt3486efe-trpbf Summary of contents
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... LEDs are disconnected and overtemperature protection. The LT3486 is available in a space saving 16-pin DFN (5mm × 3mm × 0.75mm) and 16-pin thermally enhanced TSSOP packages. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. L2 2.2µF ...
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... V = 0.2V (Note 3) FB1 FB2 FB1 FB2 S H D 0V, CTRL1 = CTRL2 = 53. 20.5k T (Note 53.6k T ORDER PART TOP VIEW NUMBER 1 16 SW2 LT3486EFE 2 15 REF 3 14 OVP2 LT3486IFE 4 SHDN FB2 11 FE PART 7 10 CTRL2 MARKING 8 9 ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are 3V, unless otherwise noted. SHDN PARAMETER Maximum Duty Cycle Switch Current Limit (SW1, SW2) Switch V CESAT Switch Leakage Current Error Amplifier Transconductance Error Amplifier Voltage Gain V , ...
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LT3486 TYPICAL PERFOR Switching Waveforms V SW2 50V/DIV I L2 500mA/DIV V SW1 10V/DIV I L1 1A/DIV V = 3.6V 0.5µs/DIV IN 8 LEDs/25mA 2 LEDs/320mA CIRCUIT OF FRONT PAGE APPLICATION LED Current vs PWM Duty Cycle ...
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TYPICAL PERFOR A CE CHARACTERISTICS W U Input Current with Output 1 and Output 2 Open Circuit 25° 63. ...
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LT3486 PI FU CTIO SW1, SW2 (Pins 1, 16): The SW Pins are the Collectors of the Internal Power Transistors. Connect the inductors and Schottky diodes to these pins. Minimize trace area at these pins to ...
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BLOCK DIAGRA W SW1 1 OVP1 3 OVERVOLT CONVERTER1 DETECTION OV1 PWM Q1 LOGIC EN1 + OSC R A3 SNS1 – PWM COMP + A2 – OV1 EN1 CONVERTER1 80k CONTROL 8 7 PWM1 CTRL1 R V ...
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LT3486 OPERATIO U Main Control Loop The LT3486 uses a constant frequency, current mode control scheme to provide excellent line and load regulation. It incorporates two identical, but fully independent PWM converters. Operation can be best understood by referring to ...
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OPERATIO U output open circuit are shown in the Typical Performance Characteristics graphs. Figure 3a shows the transient response of switcher 1 with the LEDs disconnected from the output. When the LED1 string is disconnected from the output, the voltage ...
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LT3486 APPLICATIO S I FOR ATIO U U Duty Cycle The duty cycle for a step-up converter is given by – V OUT – V OUT D CESAT where: V ...
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APPLICATIO S I FOR ATIO 8/8 LEDs 63. 39. LED CURRENT (mA) Figure 6b. Efficiency ...
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LT3486 APPLICATIO S I FOR ATIO U U The average forward current in normal operation is equal to the output current, and the peak current is equal to the peak inductor current. A Schottky diode rated suf- ...
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APPLICATIO S I FOR ATIO U U The LED current can be set by: I ≈ (200mV/R ), when V LED FB CTRL I ≈ • when V LED CTRL FB CTRL Feedback voltage variation versus ...
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LT3486 APPLICATIO S I FOR ATIO U U the figure. A PWM logic input is applied to the gate of the NMOS and the PWM pin of the LT3486. When the PWM input is taken high, the LEDs are connected ...
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TYPICAL APPLICATIO S U Li-Ion Cell Powered Driver for Camera Flash and LCD Backlighting LED1 AOT3218 320mA 5V OFF ON 0V 100k 0. OUT1 ...
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LT3486 TYPICAL APPLICATIO LEDs 25mA 5V PWM1 100Hz 100k 8.06Ω LED Current and Efficiency vs PWM Duty Cycle 3.6V IN 8/8 LEDs 80 75 EFFICIENCY 70 65 LED CURRENT ...
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TYPICAL APPLICATIO LEDs 25mA PWM FREQ 200Hz 100k LED Current and Efficiency vs PWM Duty Cycle 16/16 LEDs 80 75 EFFICIENCY 70 65 LED CURRENT ...
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LT3486 PACKAGE DESCRIPTIO 3.50 ±0.05 1.65 ±0.05 2.20 ±0.05 (2 SIDES) RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS PIN 1 TOP MARK (SEE NOTE 6) 0.200 REF NOTE: 1. DRAWING PROPOSED TO BE MADE VARIATION OF VERSION (WJED-1) IN JEDEC PACKAGE ...
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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 Package 16-Lead Plastic TSSOP (4 ...
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... 2.8V to 4.5V, IN < 1µA, QFN-24 Package SD : 2.7V to 16V 34V, IN OUT(MAX) < 1µA, ThinSOT Package SD : 2.7V to 24V 40V, IN OUT(MAX) < 16µA, DFN Package SD LT 1106 REV B • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 2006 120 100 100 < 1µA, 3486fb ...