cat4201 Catalyst Semiconductor, cat4201 Datasheet
cat4201
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cat4201 Summary of contents
Page 1
... LED current regulation. A single RSET resistor sets the full scale LED string current up to 350mA from supplies as high as 28V. The switching architecture of the CAT4201 results in extremely low internal power dissipation allowing the device to be housed in a tiny package without the need for dedicated heat sinking ...
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... CAT4201 (1) Absolute Maximum Ratings Parameters VBAT, SW, CTRL RSET Switch SW peak current Storage Temperature Range Junction Temperature Range Lead Temperature Recommended Operating Conditions Parameters (2) (3) VBAT voltage SW voltage Ambient Temperature Range LED Current Switching Frequency ELECTRICAL CHARACTERISTICS V = 13V, ambient temperature of 25ºC (over recommended operating conditions unless specified otherwise) ...
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... Characteristics subject to change without notice = 4.7μ 10μ 25°C unless otherwise specified 1 2 AMB Idle Mode Supply Current (CTRL = 0V +25°C -40°C + 85° CAT4201 200 150 100 INPUT VOLTAGE [V] RSET Voltage vs. Temperature 1.30 VIN = 13V 1.25 1 ...
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... CAT4201 Typical Operation Characteristics V = 13V 300mA 22μ LED Switching Frequency vs. Input Voltage (1 LED) 500 400 150mA 300 200 300mA 100 INPUT VOLTAGE [V] Switching Frequency vs. Temperature 500 VIN = 13V 150mA 400 300 300mA 200 100 - TEMPERATURE [°C] Efficiency vs ...
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... T = 25°C unless otherwise specified 1 2 AMB LED Current Regulation vs. Temperature -10 300 350 LED Current vs. Input Voltage (2 LEDs) 350 300 250 200 150 100 CAT4201 10 VIN = 13V - 120 TEMPERATURE [° 3.3V F 300mA ...
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... CAT4201 Typical Operation Characteristics V = 13V 300mA 22μ LED RSET Transient Response External Component Selection Table 1 provides the recommended components L and C2 that offer the best performance LED current L inductor (mA) ≥150 < 150 Note: Larger C2 capacitor values allow to reduce further the LED ripple current if needed. ...
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... RSET pin is regulated at 1.2V. A resistor connected between the RSET pin and ground sets the LED full- scale brightness current. The external resistance value and the CTRL pin voltage determine the LED current during analog dimming. LED current is 7 CAT4201 Doc. No. MD-5025 Rev. C ...
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... Reference – Figure 1. CAT4201 Simplified Block Diagram BASIC OPERATION The CAT4201 is a high efficiency step-down regulator designed to drive series connected high-power LEDs. LED strings with total forward voltages 20V can be driven with bias currents 350mA. During the first switching phase, an integrated high ...
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... Central Semiconductor Schottky diode CMDSH05-4 (40V, 500mA rated) is recommended. Schottky diodes rated at 400mA (or higher) continuous current are fine for most applications. Note: Schottky diodes with extremelly low forward voltages (V not recommended, as they may cause an increase in the LED current. 9 CAT4201 L I rated LED current (µH) (A) ( ...
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... Figure 6. Circuit for PWM on RSET VBAT 10µF CAT4201 RSET L SW CTRL 22µH GND R2 R4 1kΩ 1kΩ R5 47kΩ VBAT CAT4201 10µF RSET CTRL 22µH GND R2 1kΩ OFF ON © Catalyst Semiconductor, Inc. Characteristics subject to change without notice Q1 NPN Q1 NPN ...
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... CAT4201 connected in parallel. Each CAT4201 is driving the LED with a current set by its RSET resistor. The resulting LED current is equal to the sum of each driver current. R5 VIN 1Ω C2 4.7µF L 300mA 33µH Figure 8. Three CAT4201 in Parallel for 1A LED 11 CAT4201 C1 U1 4.7µF D1 VBAT CAT4201 RSET R1 L1 ...
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... If the LEDs are not connected, the CAT4201 stops switching and draws very little current. At power-up with no load connected, the capacitor C2 is charged-up by the CAT4201. As soon as the bottom side of the capacitor (C2-) reaches 0 volt, as shown on Figure 9, the CAT4201 stops switching and remains in the idle mode only drawing about 0.4mA current from the supply ...
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... All dimensions are in millimeters. Angles in degrees. (2) Complies with JEDEC standard MO-193. © Catalyst Semiconductor, Inc. Characteristics subject to change without notice SYMBOL θ θ CAT4201 MIN NOM MAX 1.00 0.01 0.05 0.10 0.80 0.87 0.90 0.30 0.45 0.12 0.15 0.20 2.90 BSC 2.80 BSC 1.60 BSC 0.95 TYP 0.30 0.40 0.50 0.60 REF 0.25 BSC 0º ...
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... All packages are RoHS-compliant (Lead-free, Halogen-free). (2) The standard plated finish is NiPdAu on all pins. (3) The device used in the above example is a CAT4201TD-GT3 (TSOT-23, NiPdAu, Tape & Reel). (4) For additional package and temperature options, please contact your nearest Catalyst Semiconductor Sales office. Doc. No. MD-5025 Rev. C ...
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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. ...