lt3474efe-trpbf Linear Technology Corporation, lt3474efe-trpbf Datasheet
lt3474efe-trpbf
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lt3474efe-trpbf Summary of contents
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... PWM architecture provides fast transient response and cycle-by-cycle current limiting. Frequency foldback and thermal shutdown provide additional protection. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Patent Pending 0.22μF 10μH ...
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... LT3474EFE#TRPBF LT3474IFE#PBF LT3474IFE#TRPBF LT3474EFE-1#PBF LT3474EFE-1#TRPBF LT3474IFE-1#PBF LT3474IFE-1#TRPBF Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. Consult LTC Marketing for information on non-standard lead based finish parts. ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T PARAMETER Reference Voltage Line Regulation Reference Voltage Load Regulation V Pin Bias Current (Note 4) ADJ Switching Frequency Maximum Duty Cycle Foldback Frequency SHDN Threshold (to Switch) SHDN Pin Current (Note ...
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LT3474/LT3474 TYPICAL PERFOR A CE CHARACTERISTICS LED Current vs V ADJ 1000 T = 25°C A 800 600 400 200 0 0 0.25 0.5 0.75 1 1.25 V (V) ADJ 3474 GO3 Current Limit vs Duty Cycle 2.5 ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Boost Pin Current 25° 500 750 1000 1250 1500 250 SWITCH CURRENT (mA) 3473 G12 Schottky Reverse Leakage ...
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LT3474/LT3474 CTIO S DNC (Pins 1, 16): Do not connect external circuitry to these pins, or tie them to GND. Leave the DNC pins floating. OUT (Pin 2): The OUT pin is the input to ...
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W BLOCK DIAGRA INT REG SHDN 10 AND UVLO Σ SLOPE COMP R T OSC FREQUENCY FOLDBACK – REF 11 PWM 14 V ADJ ...
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LT3474/LT3474 APPLICATIO S I FOR ATIO Operation The LT3474 is a constant frequency, current mode regu- lator with an internal power switch capable of generating a constant 1A output. Operation can be best understood by referring to the ...
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U U APPLICATIO S I FOR ATIO The switch driver operates either from V BOOST pin. An external capacitor and internal Schottky diode are used to generate a voltage at the BOOST pin that is higher than the input supply. ...
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LT3474/LT3474 APPLICATIO S I FOR ATIO Setting the Switching Frequency The LT3474 uses a constant frequency architecture that can be programmed over a 200kHz to 2MHz range with a single external timing resistor from the R The current ...
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U U APPLICATIO S I FOR ATIO Inductor Selection and Maximum Output Current A good first choice for the inductor value is 900 kHz • OUT F f where V is the voltage ...
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LT3474/LT3474 APPLICATIO S I FOR ATIO To maintain output regulation, this peak current must be less than the LT3474’s switch current limit least 1.6A (1.5A at 125°C) at low duty cycles and LIM decreases ...
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U U APPLICATIO S I FOR ATIO A final caution is in order regarding the use of ceramic capacitors at the input. A ceramic input capacitor can combine with stray inductance to form a resonant tank circuit. If power is ...
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LT3474/LT3474 APPLICATIO S I FOR ATIO Diode Selection The catch diode (D1 from Figure 1) conducts current only during switch off time. Average forward current in normal operation can be calculated from – V ...
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U U APPLICATIO S I FOR ATIO BOOST and BIAS Pin Considerations The capacitor and internal diode tied to the BOOST pin generate a voltage that is higher than the input voltage. In most cases, a 0.22μF capacitor will work ...
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LT3474/LT3474 APPLICATIO S I FOR ATIO To minimize the error from variations in V use resistors with a parallel resistance of less than 4k. Use resistors with a series resistance of 5.11k or greater so as not to ...
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U U APPLICATIO S I FOR ATIO LED Voltage Range The LT3474 can drive LED voltages from 2.4V to 12V. The LT3474-1 can drive LED voltages from 2.4V to 30V. Be careful not to exceed the ABSMAX rating of the ...
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LT3474/LT3474-1 U TYPICAL APPLICATIO S Step-Down 1A LED Driver with PWM Dimming 36V C1 V BOOST 2.2μF IN 50V SHDN SW LT3474 R BIAS T REF OUT V PWM R1 ADJ 80.6k V LED C C4 ...
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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 represen- tation 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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... Step-Up Regulator with Dual Rail to Rail Current Sense LT3479 3A, Full Featured DC/DC Converter with Soft-Start and Inrush Current Protection Burst Mode is a registered trademark of Linear Technology Corporation. ThinSOT is a trademark of Linear Technology Corporation. Linear Technology Corporation 20 1630 McCarthy Blvd., Milpitas, CA 95035-7417 ...