CAT4240_0711 CATALYST [Catalyst Semiconductor], CAT4240_0711 Datasheet
CAT4240_0711
Related parts for CAT4240_0711
CAT4240_0711 Summary of contents
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Watt Boost LED Driver FEATURES Switch Current Limit 750mA Drives High Voltage LED strings (38V 94% Efficiency Low Quiescent Ground Current 0.6mA 1MHz Fixed Frequency Low noise Operation Soft start “in-rush” current limiting Shutdown current less than ...
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CAT4240 ABSOLUTE MAXIMUM RATINGS Parameters voltage IN ¯¯¯¯¯ voltage SHDN SW voltage Storage Temperature Range Junction Temperature Range Lead Temperature RECOMMENDED OPERATING CONDITIONS Typical application circuit with external components are shown on page 1. Parameters V IN ...
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TYPICAL CHARACTERISTICS VIN = 5V 13V 25ºC, typical application circuit unless otherwise specified. L AMB Quiescent Current vs. VIN (Not Switching) 200 V = 0.4V FB 150 100 50 3.0 3.5 4.0 4.5 INPUT VOLTAGE [V] ...
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CAT4240 TYPICAL CHARACTERISTICS VIN = 5V 13V 25ºC, typical application circuit unless otherwise specified. L AMB LED Current vs. Input Voltage 350 RSET = 1Ω VOUT = 19.5V 300 250 200 RSET = 2Ω VOUT = ...
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TYPICAL CHARACTERISTICS VIN = 5V 13V 25ºC, typical application circuit unless otherwise specified. L AMB Maximum Output Current 500 400 VOUT = 20V 300 200 100 INDUCTOR ...
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CAT4240 PIN DESCRIPTION VIN is the supply input for the internal logic. The device is compatible with supply voltages down to 2.8V and up to 5.5V recommended that a small bypass ceramic capacitor (4.7μF) be placed between the ...
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DEVICE OPERATION The CAT4240 is a fixed frequency (1MHz), low noise, inductive boost converter that provides a constant current with excellent line and load regulation. The device uses a high-voltage CMOS power switch between the SW pin and ground to ...
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CAT4240 APPLICATION INFORMATION External Component Selection Capacitors The CAT4240 only requires small ceramic capacitors of 4.7μF on the inductor input, 1µF on the VIN pin and 1µF on the output. Under normal condition, a 4.7µF input capacitor is sufficient. For ...
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OPEN LED PROTECTION In the event of an “Open LED” fault condition, the CAT4240 will continue to boost the output voltage with maximum power until the output voltage reaches approximately 40V. Once the output exceeds this level, the internal circuitry ...
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CAT4240 DIMMING CONTROL There are several methods available to control the LED brightness. ¯¯¯¯¯ Pin PWM signal on the SHDN LED brightness dimming can be done by applying a ¯¯¯¯¯ input. The LED current is PWM signal to the SHDN ...
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BOARD LAYOUT The CAT4240 is a high-frequency switching regulator. The traces that carry the high-frequency switching current have to be carefully laid out on the board in order to minimize EMI, ripple and noise in general. The thicker lines on ...
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CAT4240 PACKAGE OUTLINE DRAWING (1)(2) TSOT-23 5-Lead (TD TOP VIEW b SIDE VIEW For current Tape and Reel information, download the PDF file from: http://www.catsemi.com/documents/tapeandreel.pdf. Notes: (1) All dimensions are in millimeters, angles in degrees. (2) Complies with ...
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EXAMPLE OF ORDERING INFORMATION Prefix Device # Suffix CAT 4240 TD Product Number 4240 Optional Company ID Package TD: Thin SOT-23 (Lead-free, Halogen-free) SERIES LED DRIVERS Part Number CAT4137 CMOS Boost Converter – White LED Driver CAT4237 High Voltage CMOS ...
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REVISION HISTORY Date Rev. Reason 05/31/2007 A Initial Issue Update Absolute Maximum Ratings 10/17/2007 B Update Package Outline Drawing Update Simplified Block Diagram Update Device Operation text 11/06/07 C Update Board Layout figure numbers Update Series LED Drivers table Copyrights, ...