CAT4137TD CATALYST SEMICONDUCTOR, CAT4137TD Datasheet
CAT4137TD
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CAT4137TD Summary of contents
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... APPLICATIONS LCD Backlighting Cellular Phones Handheld Devices Digital Cameras ORDERING INFORMATION Quantity Part Number Package per Reel (1) CAT4137TD-T3 TSOT23-5 (2) CAT4137TD-GT3 TSOT23-5 Notes: (1) Matte-Tin Plated Finish (RoHS-compliant). (2) NiPdAu Plated Finish (RoHS-compliant). PIN CONFIGURATION TSOT-23 5-Lead 1mm max height GND 3 FB (Top View) © ...
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... V 0.4 0.7 V 0.7 1 1.3 MHz 250 300 400 mA 1.0 2.0 Ω µA 150 ºC 20 º 1 © Catalyst Semiconductor, Inc. Characteristics subject to change without notice ...
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... Switching Frequency vs. Supply Voltage 1.10 1.05 3 LEDs at 20mA 1.00 0.95 0.90 2.5 3.0 3.5 INPUT VOLTAGE [V] © Catalyst Semiconductor, Inc. Characteristics subject to change without notice Quiescent Current vs. VIN (Switching) 1.00 0.75 0.50 0.25 0.00 4.5 5.0 2.5 FB Pin Voltage vs. Output Current ...
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... CAT4137 =25ºC, unless otherwise specified. AMB LED Current Regulation 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 INPUT VOLTAGE [V] VIN = 4. VIN = 3. LED CURRENT [mA] VIN = 4.2V 90 VIN = 3. LED CURRENT [mA] © Catalyst Semiconductor, Inc. Characteristics subject to change without notice 30 30 ...
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... Under Voltage Lock Out vs. Temperature 2.2 2.1 2.0 1.9 1.8 1.7 1.6 -50 - TEMPERATURE [°C] Switching Waveforms (3 LEDs in Series) © Catalyst Semiconductor, Inc. Characteristics subject to change without notice Shutdown Voltage vs. Input Voltage 1.0 0.8 0.6 0.4 0 100 3.0 Switching Frequency vs. Temperature 1.10 1 ...
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... VOUT = 10V 100 VOUT = 17V 20 0 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 INPUT VOLTAGE [V] Doc. No. MD-5012 Rev. B =25ºC, unless otherwise specified. AMB Line Transient Response (3V – 5.5V) 6 Characteristics subject to change without notice CAT4137 © Catalyst Semiconductor, Inc. ...
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... Shutdown pin (Logic Low). Set high to enable the driver. 5 VIN Power Supply input. © Catalyst Semiconductor, Inc. Characteristics subject to change without notice SW pin is the drain terminal of the internal low resistance power switch. The inductor and the Schottky diode anode should be connected to the SW pin ...
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... Oscillator – – – Current Sense 8 CAT4137 V OUT SW C2 Over Voltage Protection Driver PWM I LED & N Logic GND FB © Catalyst Semiconductor, Inc. Characteristics subject to change without notice In the R1 15Ω ...
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... PANASONIC ELJ-PC220 LED CURRENT [mA] Figure 1. Efficiency for various inductors © Catalyst Semiconductor, Inc. Characteristics subject to change without notice Schottky Diode small ceramic The current rating of the Schottky diode must exceed the peak current flowing through it. The Schottky diode performance is rated in terms of its forward voltage at a given current ...
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... In 2-LED configuration, the CAT4137 can be powered from two AA alkaline cells or from a Li-ion battery. Doc. No. MD-5012 Rev. B Efficiency vs. LED Current, Two LEDs D V OUT C2 1µF 20mA = 300mV FB R1 15Ω 10 CAT4137 100 95 VIN = 3. VIN = LED CURRENT [mA] © Catalyst Semiconductor, Inc. Characteristics subject to change without notice 40 ...
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... The recommended PWM frequency range is from 100Hz to 4kHz. Switching waveforms PWM on SHDN Figure 2. PWM at 1kHz Figure 3. PWM at 4kHz © Catalyst Semiconductor, Inc. Characteristics subject to change without notice 2. Filtered PWM signal A filtered PWM signal can be used as a variable DC voltage that can be used to control the LED current. ...
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... Schottky diode (open- circuit). Open LED Power-up Waveforms D V OUT C2 0.22µF = 300mV FB R1 15Ω 4.5 5.0 12 CAT4137 This protection © Catalyst Semiconductor, Inc. Characteristics subject to change without notice ...
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... SHDN C 1 GND Figure 4. Closed-switch current loop © Catalyst Semiconductor, Inc. Characteristics subject to change without notice Capacitor C1 has to be placed as close as possible to the VIN pin and GND. The capacitor C2 has to be connected separately to the top LED anode. A ground plane under the CAT4137 allows for direct connection of the capacitors to ground ...
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... L1 L2 θ θ CAT4137 NOM MAX 1.00 0.05 0.10 0.87 0.90 0.45 0.15 0.20 2.90 BSC 2.80 BSC 1.60 BSC 0.95 TYP 0.40 0.50 0.60 REF 0.25 BSC 0º 8º END VIEW © Catalyst Semiconductor, Inc. Characteristics subject to change without notice ...
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... All packages are RoHS-compliant (Lead-free, Halogen-free). (2) The standard lead finish is NiPdAu. (3) The device used in the above example is a CAT4137TD–GT3 (TSOT-23, NiPdAu Plated Finish, Tape & Reel 3000). (4) For Matte-Tin package option, please contact your nearest Catalyst Semiconductor Sales office. © Catalyst Semiconductor, Inc. ...
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... Catalyst Semiconductor products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications intended to support or sustain life, or for any other application in which the failure of the Catalyst Semiconductor product could create a situation where personal injury or death may occur. ...