SC4503TSKTRT Semtech, SC4503TSKTRT Datasheet
SC4503TSKTRT
Specifications of SC4503TSKTRT
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SC4503TSKTRT Summary of contents
Page 1
... White LED Drivers D1 VOUT 12V, 0. 15pF 432k C2 4.7µF R2 49.9k Figure 1(b). Effi ciency of the 5V to 12V Boost Converter 1 SC4503 1.3MHz Step-Up Switching Regulator with 1.4A Switch Efficiency vs Load Current 95 1.3MHz 12V OUT 55 50 0.001 0.010 0.100 1.000 Load Current (A) www.semtech.com ...
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... Feedback Voltage Feedback Line Voltage Regulation FB Pin Bias Current Switching Frequency Minimum Duty Cycle Maximum Duty Cycle Switch Current Limit Switch Saturation Voltage Switch Leakage Current V Quiescent Supply Current IN V Supply Current in Shutdown IN 2007 Semtech Corp. Symbol SHDN θ θ STG T ...
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... Semtech Corp < 85°C J Conditions SHDN/ 1.8V SHDN/ SHDN/SS Ordering Information SC4503TSKTRT 5 IN SC4503EVB Notes: 4 SHDN/SS (1) Available in tape and reel only. A reel contains 3,000 devices. (2) Available in lead-free package only. Device is WEEE and RoHS compliant. 3 Min Typ Max 1.4 2 0.4 22 ...
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... The inverting input of the error amplifi er. Tie to an external resistive divider to set the 5 FB output voltage. 6,7 GND Ground. Tie to ground plane. 8 N.C. No Connection. EDP Solder to the ground plane of the PCB. 2007 Semtech Corp. Ordering Information Device SC4503WLTRT GND GND ...
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... POWER MANAGEMENT Block Diagram IN 5 SHDN/SS VOLTAGE 4 REFERENCE SHUTDOWN 1.25V + 2007 Semtech Corp. REF NOT READY T > 155° ° ° ° C THERMAL J CLK - PWM + OSCILLATOR Figure 2. SC4503 Block Diagram 5 SC4503 I-LIMIT ILIM - + + Σ Σ Σ Σ ISEN - + SLOPE COMP GND www ...
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... Temperature (° C) Switch Saturation Voltage vs Switch Current 400 125° C 300 25° C 200 100 -40° 0.0 0.5 1.0 Switch Current (A) 2007 Semtech Corp. 75 100 125 75 100 125 1.5 2.0 6 SC4503 Switching Frequency vs Temperature 1.5 1.4 1.3 1.2 1.1 1.0 ...
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... Shutdown Pin Voltage (V) Switch Current Limit vs Shutdown Pin Voltage 2 50% 2.0 -40° C 1.5 25° C 1.0 0.5 0.0 1.2 1.4 1.6 Shutdown Pin Voltage (V) 2007 Semtech Corp. -40° 1.5V FB 1.5 2.0 85° C 1.8 2.0 7 SC4503 Shutdown Pin Current vs Shutdown Pin Voltage ...
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... SHDN SS will ramp up slowly. The error amplifi er output, which is 2007 Semtech Corp. clamped by D1 and Q1, follows the voltage at the pin. The input inductor current, which is in turn controlled by the error amplifi er output, also ramps up gradually. ...
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... Semtech Corp. where worth noting that I ratio derivation. Equation (4) therefore over-estimates the maximum output current, however useful fi rst-order approximation. ...
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... In current-mode control, the slope of the modulating (sensed switch current) ramp should be steep enough to 2007 Semtech Corp. lessen jittery tendency but not so steep that large fl ux swing decreases effi ciency. For continuous-conduction mode (5) operation, inductor ripple current ΔI 0. good compromise. Setting ΔI and ...
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... RMS value of: − tantalum capacitor is used, then its ripple current rating in addition to its ESR will need to be considered. 2007 Semtech Corp. When the switch is turned on, the output capacitor supplies the load current I (Figure 4). The output ripple voltage ...
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... Driven from a Logic Gate with Soft-start (1.7V < V (e) Driven from an Open-collector NPN Transistor with Soft-start and (f) Driven from a Logic Gate (whose V 2007 Semtech Corp. Pulling the drawing less than 1µA from the input power supply. For voltages above 2V and below 0.4V, the ...
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... Feed-Forward Compensation Figure 6 shows the equivalent circuit of a boost converter. Important poles and zeros of the overall loop response are: ω Low frequency integrator pole, 2007 Semtech Corp. Output fi lter pole, Compensating zero, Right half plane (RHP) zero reduces the shut- ...
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... Figure 10(a switched between 90mA and 280mA. OUT 2007 Semtech Corp. Board Layout Considerations is optimized for In a step-up switching regulator, the output fi lter capacitor, 4 the main power switch and the rectifying diode carry pulse currents with high di/dt ...
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... POWER MANAGEMENT Typical Application Circuits 5V C1 4.7µF Figure 9. Driving Two 6 White LED Strings from 5V. Zener diode D from over-voltage damage when both LED strings become open. 2007 Semtech Corp 10µH ZHCS400 + R3 D2 24V 54.9k MM5Z24VT1 SC4503 220pF SHDN/SS FB 301k GND ...
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... Typical Application Circuits VIN 3.3V Figure 10(a). 3.3V to 12V Boost Converter with Soft-start Efficiency vs Load Current 95 1.3MHz 0.001 0.010 Load Current (A) Figure 10(b). Effi ciency vs Load Current 2007 Semtech Corp 2.7µH 10BQ015 15k SC4503 C1 2.2µ SHDN/SS FB GND C3 56nF ...
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... L1: TDK VLF4012AT C1: Murata GRM188R60J475K C2: Murata GRM21BR60J106K Figure 11(a). Single Li-ion Cell to 5V Boost Converter 40µs/div Upper Trace : Output Voltage, AC Coupled, 0.2V/div Lower Trace : Inductor Current, 0.5A/div Figure 11(c). Load Transient Response. I between 0.1A and 0.5A 2007 Semtech Corp. D1 VOUT 5V 10BQ015 10pF ...
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... Figure 12(a). Single Li-ion Cell to 3.3V SEPIC Converter. Efficiency vs Load Current 3.3V OUT 0.001 0.010 Load Current (A) Figure 12(b). Effi ciency vs Load Current 2007 Semtech Corp 3.3µH 2.2µ 8.06k SC4503 SHDN/SS FB GND C3 2 0.22µF L1 and L2: Coiltronics DRQ73-3R3 ...
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... CH1 : OUT1 Voltage, 5V/div CH2 : OUT2 Voltage, 20V/div CH3 : OUT3 Voltage, 5V/div CH4 : RUN Voltage, 5V/div Figure 13(b). TFT Power Supply Start-up Transient as the RUN Voltage is Stepped from 0 to 3.3V 2007 Semtech Corp 0.1µ 4.7µH 10BQ015 ...
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... POWER MANAGEMENT EVB Schematic 12VOUT 432K N.P. C4 15pF R5 49.9K 12VOUT 432K C4 15pF R5 49.9K 2007 Semtech Corp. D1 SS13 N.C. SW 10uF 7 GND SW 6 GND VIN 5 FB SHDN/ SC4503_MLPD D1 SS13 N.P. 10uF SC4503 20 L1 4.7uH 5VIN C1 1 10uF 47K OFF/ JP1 100nF L1 4.7uH ...
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... DIMENSIONS "E1" AND "D" DO NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS. 4. REFERENCE JEDEC STD MO-193, VARIATION AB. Land Pattern - TSOT-23 X (C) P NOTES: 1. THIS LAND PATTERN IS FOR REFERENCE PURPOSES ONLY. CONSULT YOUR MANUFACTURING GROUP TO ENSURE YOUR COMPANY'S MANUFACTURING GUIDELINES ARE MET. 2007 Semtech Corp. A DIM E ...
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... POWER MANAGEMENT Outline Drawing - 8 Lead 2X2mm MLPD-W INDICATOR (LASER MARK) aaa C NOTES: Land Pattern - 8 Lead 2X2mm MLPD-W Contact Information Phone: (805) 498-2111 Fax: (805) 498-3804 2007 Semtech Corp DIM A E PIN .059 .063 .067 1.50 1.60 1. .031 .035 .039 0.80 0.90 1.00 ...