SC4539 Semtech Corporation, SC4539 Datasheet
SC4539
Related parts for SC4539
SC4539 Summary of contents
Page 1
... A small external capacitor and series resistor control soft-start and loop compensation. Over-voltage detection protects the SC4539 if the LED pin is fl oating or shorted to ground. The SC4539 is available in an MLPD-8 pin 2mm x 2mm x 0.6mm package, with a rated temperature range of -40°C to +85° ...
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... ISET 3 COMP 4 MLPD: 2mm x 2mm 8 Lead θ = 74°C/W JA Marking Information FF0 yw FF0 = Marking code for SC4539 yw = Date Code Ordering Information Note (1) Available in tape and reel only. A reel contains 3,000 devices. (2) Lead-free package only. Device is WEEE and RoHS compliant. GND 7 BL ...
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... T ISET A Conditions Min Typ V rising 2.40 2.60 IN 120 Not switching 1.8 EN tied to GND 0.1 1. 5.5V ±0. rising 155 J 20 680 800 = 3.2V 25° 100 500 SC4539 (2) (°C/ 25ºC. A Max Units 2. μA V 0.8 V ±1 μA °C °C 920 kHz % ns 850 mA 3 ...
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... 20V OUT = 0V 5.5V 0.01 OUT IN Applied to EN pin 100 200Hz on EN pin 25° 3.0 to 5.5V ±0.05 IN 0.35 0.5 230 1.3 SC4539 Max Units 1 μA 450 mV μ μA 1 μA 50k Hz 100 % 30 mA 3.5 % 0.1 μA mA A/A μs 4 ...
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... V ( unless otherwise noted. LED IN Effi ciency vs. Output Voltage (V) OUT Effi ciency vs. Input Voltage 90 6 LED LED 2.8 3.3 4.4 3.9 V (V) IN Normalized I vs. Output Voltage BL 6.0 4.0 2.0 0.0 -2.0 -4.0 -6 (V) OUT SC4539 IN 2. 5.0 5 ...
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... PWM Operation at 50kHz and 15% Duty Cycle V (20V/div) LX (20mA/div) OUT V (20V/div) OUT V (2V/div) EN 4μs/div PWM Operation at 32kHz and 10% Duty Cycle V (20V/div) LX (20mA/div) OUT V (20V/div) OUT V (2V/div) EN 10μs/div I Error vs. PWM Frequency at 50% Duty Cycle BL 6.0 4.0 2.0 0.0 -2.0 -4.0 -6.0 0.1 1 PWM Frequency (kHz) SC4539 10 100 6 ...
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... OUT V (5V/div 2.8V IN 1μs/div = 3.6V IN 1μs/div 40μs/div Typical Waveforms (20V/div (50mV/div (50V/div) OUT 1μs/div Start-Up Response V (20V/div (20mA/div) OUT V (10V/div) OUT V (2V/div) EN 100μs/div Normalized I vs. Input Voltage BL 3.5 2.3 1.2 0.0 -1.2 -2.3 -3.5 2.8 3.25 3.7 4.15 4.6 V (V) IN SC4539 = 5.5V IN 5.05 5.5 7 ...
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... LED constant current sink — connect this pin to the cathode of the LED Ground Power supply pin — bypass this pin with a capacitor close to the pin Pad for heatsinking purposes — connect to the ground plane using multiple vias. Not connected internally. SC4539 resistor and 47nF capacitor in series to GND. Ω 8 ...
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... Block Diagram Thermal UVLO Shutdown 8 IN Reference and Internal www.DataSheet4U.com Regulator OUT 5 OVP Comparator OSC Error Signal Selection and Summation LED Setpoint 3 ISET SC4539 1 LX RSENSE 7 GND Sense Amp 4 COMP 9 ...
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... LED current regulator. The LED current set point is chosen using an external resistor, while the PWM controller operates inde- pendently to keep the current in regulation. The SC4539 receives information from the internal LED current regu- lator and drives the output to the proper voltage with no user intervention ...
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... the duty cycle for continuous operation. Effi ciency (η) can be approximated by using the curves provided in the Typical Characteristics section. Table 1 lists inductors that have been proven to work with SC4539. Table 1 -- Recommended Inductors Value DCR Rated Part Number (μH) (Ω ...
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... The Central Semiconductor Corporation CMOSH- suitable diode for this application. Selection of Other Components R sets the maximum load current for the SC4539. Use ISET www.DataSheet4U.com the following equation to select the proper value 230×V ...
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... DIM MIN NOM MAX MIN NOM MAX - - A .018 .024 0.45 0. .000 .002 0.00 0.05 A1 (.006) (0.1524 .007 .010 .012 0.18 0.25 0.30 D .075 .079 .083 1.90 2.00 2.10 D1 .061 .067 .071 1.55 1.70 1.80 E .075 .079 .083 1.90 2.00 2.10 E1 .026 .031 .035 0.65 0.80 0.90 e .020 BSC 0.50 BSC L .012 .014 .016 0.30 0.35 0. aaa .003 0.08 bbb .004 0.10 SC4539 13 ...
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... FAILURE MAY COMPROMISE THE THERMAL AND/OR FUNCTIONAL PERFORMANCE OF THE DEVICE. Contact Information Semtech Corporation Power Management Products Division 200 Flynn Road, Camarillo, CA 93012 Phone: (805) 498-2111 Fax: (805) 498-3804 www.semtech.com SC4539 DIMENSIONS DIM INCHES MILLIMETERS (.077) (1.95 .047 1.20 H .067 1.70 K ...