SC443ULTRT Semtech, SC443ULTRT Datasheet
SC443ULTRT
Specifications of SC443ULTRT
Related parts for SC443ULTRT
SC443ULTRT Summary of contents
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... LED failure and wire disconnectons. The internal thermal shutdown protects the IC from overheating at abnormal conditions. The SC443 is available in a 3mm × 3mm × 0.6mm MLP-UT 6 Lead-free package. SW VIN VOUT OVPIN OVPIN COMP AGND AGND SS SC443 3 IO1 3 - FSET IOSET EN IOGND PWM PGND SC443 www.semtech.com ...
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... Semtech Corp. Ordering Information SC443ULTRT SC443EVB Notes: () Available in tape and reel only ...
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... Switch Current Limit Switch Saturation Voltage Switch Leakage Current © 2008 Semtech Corp. Recommended Operating Conditions Supply Input Voltage ……………………………… 4.5 to 2V Maximum Output Voltage…………………………………42V Maximum LED Current … ...
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... Backlight Current Accuracy LED Current Matching Overshoot Protection Threshold Maximum LED Current IO Off Leakage Current Over-Temperature Protection Thermal Shutdown Temperature Thermal Shutdown Hysteresis Notes: () Guaranteed by design. © 2008 Semtech Corp < 85° 4.02kΩ, FSET = 40.2kΩ IOSET Symbol Conditions I VCOMP = 0.5V ° ...
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... OVPIN 1.9 1.8 1.7 -40 25 Temperature (°C) OVPIN Threshold vs. Temperature 1.54 1.53 1.52 1.51 1.50 1.49 -40 25 Temperature (°C) © 2008 Semtech Corp. Switching Frequency vs. Temperature 880 Rising R =40.2k FSET 850 820 790 760 730 Falling 700 670 640 -40 105 COMP Current vs ...
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... Temperature (°C) Switching frequency setting Switching Frequency (MHz) Switching Frequency Vs. RFSET © 2008 Semtech Corp. Efficiency vs. Input Voltage VOUT=33V, D1=SS14, L1=B1000AS-220M, Co=10uF 4.5VIN 21VIN 105 PWM Dimming Duty Cycle Vin=12V, L= 15uH, Cout= 10uF, 10*LED,3string, Ta=25°C, Switching Frequency=800KHz 800KHz,800KHz ,B1000AS220M(22uH) , SS14, 3X7 150ohm per channel 30mA ...
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... Time(0.s/DIV) Condition: VIN=2V, Load=30mA x3 string, 0LEDs per string Main Power Switching Waveform 50mV/DIV 200mA/DIV 0V/DIV Time(us/DIV) Condition: VIN=4.5V, Load=30mA x3 string, 0LEDs per string © 2008 Semtech Corp. Shutdown by Vin VOUT V/DIV VOUT 0.5V/DIV SS SS VIN VIN 0.5V/DIV ...
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... Time(5ms/DIV) Condition: VIN=2V, Load=30mA x3 string, 0LEDs per string PWM Dimming 2V/DIV 5V/DIV A/DIV 20V/DIV Time(0.s/DIV) Condition: VIN=2V, Load=30mA x3 string, 0LEDs per string © 2008 Semtech Corp. Adaptor Plug-in Adaptor Plug-in VOUT SS 0V/DIV V/DIV 0.5V/DIV IL 20V/DIV SW Time(0us/DIV) ...
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... Enable the device including requlator and LED drivers. T Thermal Pad Thermal pad for heatsinking purposes — connect to ground plane using multiple vias — not connected internally. Table 1. EN STATUS 0 backlight disable backlight enable Note: When the boost is turned OFF and disabled. © 2008 Semtech Corp. SC443 www.semtech.com 9 ...
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... PROTECTION IO2 IO1 LED CURRENT SETTING IOSET IOGND VOUT OVP OVPIN OVP Fault 0.8mA 0.8mA Detect SS HICCUP 5 4 © 2008 Semtech Corp. 3 HICCUP DISABLE1 CURRENT SOURCE HICCUP CONTROL 3V3 LOGIC HICCUP 5uA 5uA 1.5uA 1.5uA Figure 1. SC443 Block Diagram 3 2 FSET ...
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... IOSET I is the output current of each string in mA. LED © 2008 Semtech Corp. Start-Up During start-up, when the VIN pin voltage reaches its UVLO threshold and both EN and PWM signals are set to high, the SS pin begins to source 5µA to the SS capacitor and its voltage begins to rise from 0V to its end value (2 ...
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... IC and output capacitor in the event of an open-circuit condition. The output voltage of the boost converter is detected at © 2008 Semtech Corp. the OVPIN pin. If the voltage at the OVPIN pin exceeds .5V, the boost converter will shut off and a 0.8mA pull down current source will be applied to the VOUT pin to quickly discharge the over-voltage capacitor ...
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... Additionally, PWM dimming offers customers the ability to reduce in-rush current to the output capacitor. Simply apply the PWM signal to the device at 0% duty for a © 2008 Semtech Corp. millisecond or two, and in-rush current is reduced to less than 50mA. This dim time will vary based on the number ...
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... Table 2. Recommended Inductors Inductor DR74, 4.7μH ~ 5μH IHLP-2525CZ-0, 4.7μ ~ 0μH DS85LC, 6.8μH ~ 0μH © 2008 Semtech Corp. Output Capacitor Selection ), it The next task in design is targeting the proper amount boundary of ripple voltage due to the constant-current LED loads. ...
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... IO through IO3 and should return to analog ground. IOGND should also be connected to AGND. © 2008 Semtech Corp. Since there is pad at the bottom of the SC443 for heat dissipation, a copper area right underneath the pad is used for better heat spreading. On the bottom layer of the board another copper area connected through vias to the top layer, is used for better thermal performance ...
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... C7 C7 2.2u 2. 20K 20K PWM R10 R10 4.02K 4.02K 68nF 68nF B Evaluation Board Bill of Materials Item © 2008 Semtech Corp 15uH 15uH C6 C6 2.2u 2. 10uF 10uF OPT 17 PAD 5 16 PWM OVPIN FSET AGND SC443 SC443 8 13 I0SET IO1 R6 R6 1.5K 1. 22nF ...
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... Layout Illustration Diagrams 3. TOP PCB TOP 5. Components on TOP COMPONENT TOP © 2008 Semtech Corp. 4. BOTTOM PCB BOTTOM 6. Components on BOTTOM COMPONENT BOTTOM www.semtech.com SC443 7 ...
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... Outline Drawing - MLP-UT16 A PIN 1 INDICATOR (LASER MARK) A aaa NOTES: 1. CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES). 2. COPLANARITY APPLIES TO THE EXPOSED PAD AS WELL AS THE TERMINALS. 3. DAP IS 1.90 x 1.90mm. © 2008 Semtech Corporation © 2008 Semtech Corp SEATING PLANE C D1 e/2 LxN E bxN D/2 bbb ...
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... CONSULT YOUR MANUFACTURING GROUP TO ENSURE YOUR COMPANY'S MANUFACTURING GUIDELINES ARE MET. 3. THERMAL VIAS IN THE LAND PATTERN OF THE EXPOSED PAD SHALL BE CONNECTED TO A SYSTEM GROUND PLANE. FAILURE MAY COMPROMISE THE THERMAL AND/OR FUNCTIONAL PERFORMANCE OF THE DEVICE. Contact Information © 2008 Semtech Corp. DIM ...