SC440MLTRT Semtech, SC440MLTRT Datasheet
SC440MLTRT
Specifications of SC440MLTRT
Related parts for SC440MLTRT
SC440MLTRT Summary of contents
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... The short LED protection function can be disabled. The internal thermal shutdown protects the IC from overheating at abnormal conditions. The SC440 is available in a common 4mm x 4mm x1mm MLPQ-24 package VIN VOUT SCP_EN OVPIN EN FFLAG OVPRTN 10 SC440 PWM 6 IO1-6 COMP IOSET AGND IOGND SS PGND PGND EDP SC440 6 Strings www.semtech.com 1 ...
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... Marking for the 4mm x 4mm x1mm MLPQ – 24 Lead Package: Nnnnn = Part number (Example: SC440) yyww = Date Code (Example: 0752) xxxxx = Semtech Lot No. (Example: E9010 xxxxx = © 2010 Semtech Corp. Ordering Information Device SC440MLTRT SC440EVB 20 19 Notes: PWM 18 (1) Available in tape and reel only. A reel contains 3,000 devices. ...
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... Switch Leakage Current Compensation Sourcing Current Sinking Current © 2010 Semtech Corp. Recommended Operating Conditions Supply Input Voltage …………………………… 4.5V to 21V 7.5W Maximum Output Voltage ………………………… ...
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... LED Current Matching (1) Maximum LED Current LED Short Circuit Protection Threshold I Off Leakage Current O SCP_EN Bias Over-Temperature Protection Thermal Shutdown Temperature Thermal Shutdown Hysteresis Notes: (1) Guaranteed by design. © 2010 Semtech Corp. < 85° 2kΩ. IOSET Symbol Conditions 4.5V to 21V EN_H 4.5V to 21V EN_L ...
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... LED Current (mA) OVPIN Threshold Voltage vs. Temperature 1.6 1.55 VIN = 12V 1.5 1.45 1.4 -40 - Temperature (°C) © 2010 Semtech Corp. 805 Rising 795 785 775 765 -40 5.5 5 4 -40 4 3.5 3 2.5 VIN =12V 2 1 ...
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... Temperature (°C) PWM Dimming Duty Cycle 5mA 5mA x 6 string load, 8 LEDs per string, L1= DR74-100 2x10µ Fpwm = 200 Duty Cycle % © 2010 Semtech Corp. LED Current Source SCP Threshold vs. Temperature 2.43 2.425 2.42 2.415 VIN=21V 2.41 2.405 2.4 - 0.912 0.91 ...
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... LEDs per string Main Power Switching Waveform SW 10V/DIV VOUT (AC) 50mV/DIV Time (0.5us/DIV) Conditions: VIN=5V, Load = 30mA x 6 strings, 8 LEDs per string © 2010 Semtech Corp. Shut down VIN 2V/DIV VOUT 10V/DIV IO1 5V/DIV Time (10ms/DIV) Conditions: VIN=5V, Load = 30mA x 6 strings, ...
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... LEDs per string OVP OVPIN 0.5V/DIV SS 1V/DIV FLAG 5V/DIV Time (20ms/DIV) Conditions: VIN=5V, Load = 30mA x 6 strings, 8 LEDs per string © 2010 Semtech Corp. PWM dimming PWM 2V/DIV SW 20V/DIV IO1 5V/DIV Time (5ms/DIV) Conditions: VIN=5V, Load = 30mA x 6 strings, 8 LEDs per string ...
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... Provides constant source current to LED string 2. T Thermal Pad Thermal pad for heatsinking purposes — connect — not connected internally Table 1. EN STATUS 0 backlight disable 1 backlight enable Note: When the boost is turned OFF and disabled. © 2010 Semtech Corp. SC440 www.semtech.com 9 9 ...
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... CIRCUIT PROTECTION IO3 IO2 IO1 LED CURRENT SETTING IOSET IOGND VOUT OVP OVPIN OVP OVPRTN Fault Detect SS HICCUP SCP_EN © 2010 Semtech Corp. HICCUP FAULT-1 DISABLE1 CURRENT SOURCE HICCUP CONTROL 3V3 LOGIC HICCUP 4uA 5uA Figure 1. SC440 Block Diagram OSC ILIM ...
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... IOSET I is the output current of each string in mA. LED © 2010 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 4µA to the SS capacitor and its voltage begins to rise from 0V to its end value (2 ...
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... The output voltage of the boost converter is detected at the OVPIN pin. If the voltage at the OVPIN pin exceeds 1.5V, © 2010 Semtech Corp. the boost converter will shut off and a 1mA pull down current source will be applied to the VOUT pin to quickly discharge the over-voltage capacitor ...
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... The PWM pin can be toggled by external circuitry to allow PWM dimming typical application, a microcontroller sets a register or counter that varies the pulse width on a © 2010 Semtech Corp. GPIO pin. The SC440 allows dimming over two decades in frequency (50Hz-50kHz) in order to allow compatibility with a wide range of devices, including the newest dimming strategies that avoid the audio band by using high frequency PWM dimming ...
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... Then the duty ratio is, V – Forward conduction drop of the output rectifying D diode © 2010 Semtech Corp. When the boost converter runs in DCM ( L < L takes the advantages of small inductance and quick transient response while avoiding the bandwidth- limiting instability of the RHP zero found in CCM boost converters ...
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... Murata 814-237-1431 Taiyo Yuden 408-573-4150 © 2010 Semtech Corp. Output Rectifying Diode Selection Schottky diodes are the ideal choice for SC440 due to their low forward voltage drop and fast switching speed. Table 4 shows several different Schottky diodes that work well with the SC440 ...
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... The pad at the bottom of the SC440 should be tied to the analog ground. The analog ground should be connected to the power ground at one point for better noise immunity. © 2010 Semtech Corp. SC440 www.semtech.com 16 16 ...
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... PWM GND GND 19 Case 2: Power Rail is powered up first with voltage from 2.7V to 4.2V and 5V bias voltage comes late (5 Strings, 8 LEDs per channel) Input Bias Rail Voltage R8 4.32k 2.2u P2 2.7V~ 4. 4.7n 10k © 2010 Semtech Corp. 10uF 226k 10k 10k 10k CR4 ...
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... NOT RECOMMENDED FOR NEW DESIGNS: SEE SC440A BOM for 8-LED Application ITEM © 2010 Semtech Corp. QUANTITY REFERENCE 1 CR4 LEDs SC440 PART 1nF 10μF, 50V, 1210 2.2μ, 25V, 0805 47nF 4.7n SS14 4.7μ, DR74-4R7 10k 226k 20k 10k 2 ...
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... NOT RECOMMENDED FOR NEW DESIGNS: SEE SC440A Layout Illustration Diagrams PCB TOP COMPONENT TOP © 2010 Semtech Corp. SC440 PCB B OTTOM COMPONENT B OTTOM www.semtech.com 19 19 ...
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... NOT RECOMMENDED FOR NEW DESIGNS: SEE SC440A Outline Drawing - MLPQ-24 PIN 1 INDICATOR (LASER MARK) aaa C NOTES © 2007 Semtech Corporation © 2010 Semtech Corp SEATING PLANE LxN E bxN bbb D/2 CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES). COPLANARITY APPLIES TO THE EXPOSED PAD AS WELL AS THE TERMINALS. ...
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... CONSULT YOUR MANUFACTURING GROUP TO ENSURE YOUR COMPANY'S MANUFACTURING GUIDELINES ARE MET. 2. 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 © 2010 Semtech Corp. K DIM ...