CAT37 CATALYST [Catalyst Semiconductor], CAT37 Datasheet
CAT37
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CAT37 Summary of contents
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... Low resistance (0.5 ) power switch Color LCD and keypad backlighting Cellular phones Handheld terminals The CAT37 is a DC/DC step up converter that delivers a regulated output current. Operation at a constant switching frequency of 1.2MHz allows the device to be used with very small value external inductor and ceramic capacitors ...
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... VIN GND 2 CAT37 SHDN 5-Lead SOT-23 1mm maximum height [Free Air — 1 Doc. No. 5005, Rev ...
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FB, SHDN Voltage ......................................... Voltage .......................................................... 20 V Junction Temperature ....................................... 125 ...
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V = 3.6 V,T = 25˚ 4 AMB LEDs 3 LEDs INPUT VOLTAGE [V] 110 105 100 LED CURRENT ...
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V = 3.6 V,T = 25˚ 4 AMB LEDS at 15mA 75 3 LEDs at 15mA VOUT = 10V VOUT = 10V INPUT VOLTAGE ...
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... The CAT37 device is a high efficiency, constant frequency, current regulating boost driver for white LEDs. The device includes a switch and an internally compensated loop for the regulation of the current in the LEDs. Operation can be best understood by examining the block diagram. The FB pin is regulated and the ...
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... Ceramic capacitors also make a good choice for the input capacitor, which should be mounted as close as possible to the CAT37 4.7 F input capacitor is recommended. Table 1 shows a list of several ceramic capacitor manufacturers. Consult the manufacturers for detailed information as new products and package options are introduced regularly ...
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... R determines how much LED current increases INCR when the external NMOS switch is turned ON. The CAT37 is a high-frequency switching regulator where proper PCB board layout and component placement can minimize noise and radiation and increase efficiency. To maximize efficiency, the CAT37 design has fast switch rise and fall times. To prevent radiation ...
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... SHDN GND Three LEDs with DC Level Dimming Control VIN 4 VIN SW CAT37 4 SHDN GND Four LEDs with PWM Dimming Control VIN 4 VIN SW CAT37 4 SHDN GND Efficiency - Two LEDs Dimming 18k 15mA Dimming ...
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REF 1.90 REF 3.00 MAX 2.80 MIN 1.00 MAX Doc. No. 5005, Rev. R 0.50 MAX 0.35 MIN PIN 1 3.00 MAX 2.60 MIN 0.20 MAX 0.09 MIN 0.90 MAX 0.80 MIN 0.15 MAX 0.00 MIN 0.70 MAX 0.50 ...
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TDFN 3X3 MM PACKAGE (RD4 PIN 1 INDEX AREA NOTE: 1. ALL DIMENSION ARE IN mm. ANGLES IN DEGREES. 2. COPLANARITY SHALL NOT EXCEED 0.08 mm. 3. WARPAGE SHALL NOT EXCEED 0.10 mm. 4. PACKAGE LENGTH / PACKAGE ...
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H Updated Ordering Information - part numers Changed L1 for each figure from 6.8 H Changed VIN for Typical Application from 2.7V to 4.2 Vto Changed C1 for each typical application circuit from ...
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Copyrights, Trademarks and Patents Trademarks and registered trademarks of Catalyst Semiconductor include each of the following: DPP ™ ™ Catalyst Semiconductor has been issued U.S. and foreign patents and has patent applications pending that protect its products. For ...