SC4503EVB SEMTECH [Semtech Corporation], SC4503EVB Datasheet
SC4503EVB
Related parts for SC4503EVB
SC4503EVB Summary of contents
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POWER MANAGEMENT Description The SC4503 is a 1.3MHz current-mode step-up switch- ing regulator with an integrated 1.4A power transistor. Its high switching frequency allows the use of tiny sur- face-mount external passive components. The SC4503 features a combined shutdown and ...
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POWER MANAGEMENT Absolute Maximum Ratings Absolute Maximum Ratings Exceeding the specifi cations below may result in permanent damage to the device or device malfunction. Operation outside of the parameters specifi the Electrical Characteristics section is not recommended. Parameter ...
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... T < 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 0.1 155 ...
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POWER MANAGEMENT Pin Confi guration - 2mm X 2mm MLPD Top View SHDN/SS SHDN/SS 8-LEAD 2X2mm MLPD-W Pin Descriptions - 2X2mm MLPD-W Pin Pin Name Pin ...
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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 ...
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POWER MANAGEMENT Typical Characteristics FB Voltage vs Temperature 1.30 1.25 1.20 1.15 1.10 -50 - Temperature (° Under-voltage Lockout IN Threshold vs Temperature 2.6 2.4 2.2 2.0 1.8 1.6 -50 - Temperature ...
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POWER MANAGEMENT Typical Characteristics (Cont.) Shutdown Pin Current vs Shutdown Pin Voltage 25° 85° Shutdown Pin Voltage (V) V Quiescent Current IN vs Shutdown Pin Voltage 1000 ...
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POWER MANAGEMENT Applications Information Operation The SC4503 is a 1.3MHz peak current-mode step-up switching regulator with an integrated 1.4A (minimum) power transistor. Referring to the block diagram, Figure 2, the clock CLK resets the latch and blanks the power transistor ...
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POWER MANAGEMENT Applications Information (Cont.) Duty Cycle The duty cycle boost converter in continuous-conduc- tion mode (CCM) is: − − + where V is the switch saturation voltage and V CESAT age drop across the ...
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POWER MANAGEMENT Applications Information (Cont.) − = − − Assuming that the voltage of a nearly discharged Li-ion cell is 2.6V. Using V =0.5V, V =0.3V and D=0.86 in (5), D CESAT − • < − = − Transient headroom ...
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POWER MANAGEMENT Applications Information (Cont.) Switch on duty ratio in DCM is given by, = − Higher input current ripples and lower output current are the drawbacks of DCM operation. Input Capacitor The input current in a boost converter is ...
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POWER MANAGEMENT Applications Information (Cont.) The minimum voltage for switching is 1.4V. The SHDN SS SHDN SS graph “Switch Current Limit vs. Shutdown Pin Voltage” in the “Typical Characteristics” shows that the voltage needs least 2V for ...
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POWER MANAGEMENT Applications Information (Cont.) circuit from the driving logic gate during fault condition. In Figure 5(f) the shutdown pin is driven from a logic gate whose V is higher than the supply voltage to the SC4503. OH The diode ...
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POWER MANAGEMENT Applications Information (Cont.) Figures 7(a)-7(c) show the effects of different values of inductance and feed-forward capacitance on transient re- sponses battery-operated system if C the minimum V and the maximum load step, the converter IN will ...
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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 ...
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POWER MANAGEMENT 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 ...
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POWER MANAGEMENT Typical Application Circuits L1 2.6 - 4.2V 1.5µH 3.3V OFF ON 5 < 0. 1-CELL SC4503 C1 15k LI-ION 4.7µF 4 SHDN/SS GND C3 56nF L1: TDK VLF4012AT C1: Murata GRM188R60J475K C2: Murata GRM21BR60J106K Figure 11(a). ...
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POWER MANAGEMENT Typical Application Circuits 2.6 - 4.2V 1-CELL LI-ION 1µF Figure 12(a). Single Li-ion Cell to 3.3V SEPIC Converter. Efficiency vs Load Current 3.3V OUT ...
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POWER MANAGEMENT Typical Application Circuits 3.3V 3.3V OFF ON < 0.4V RUN C1 4.7µF Figure 13(a). Triple-Output TFT Power Supply with Soft-Start CH4 CH1 CH2 CH3 400µs/div CH1 : OUT1 Voltage, 5V/div CH2 : OUT2 Voltage, 20V/div CH3 : OUT3 ...
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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 ...
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POWER MANAGEMENT Outline Drawing - TSOT-23 SEATING PLANE NOTES: 1. CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES). 2. DATUMS 3. DIMENSIONS "E1" AND "D" DO NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS. 4. REFERENCE JEDEC STD MO-193, VARIATION ...
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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 ...