SC4501STDEVB Semtech, SC4501STDEVB Datasheet
SC4501STDEVB
Specifications of SC4501STDEVB
Related parts for SC4501STDEVB
SC4501STDEVB Summary of contents
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... D08017) 4.7 (Coilcraft DO1813P) 3.3 Figure 1(b). Efficiencies 12V Boost Converters at 1 Regulator with Soft-Start Efficiency 95 10.5 H, 700KHz 4.7 H, 1.4MHz 3.3 H, 2MHz 12V OUT 50 0.0 0.1 0.2 0.3 0.4 0.5 0.6 Load Current (A) 700KHz, 1.4MHz and 2MHz. www.semtech.com SC4501 0.7 ...
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... FB Pin Bias Current Error Amplifier Transconductance Error Amplifier Open-Loop Gain COMP Source Current COMP Sink Current V Quiescent Supply Current IN V Supply Current in Shutdown IN Switching Frequency Maximum Duty Cycle Minimum Duty Cycle Switch Current Limit Switch Saturation Voltage 2005 Semtech Corp. Symbol SHDN ...
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... Shutdown Threshold Voltage Shutdown Pin Current Soft-Start Charging Current Thermal Shutdown Temperature Thermal Shutdown Hysteresis Pin Configurations TOP VIEW (10 Pin - MLPD 3mm) TOP VIEW 1 COMP SHDN GND 4 (8 Pin MSOP-EDP) 2005 Semtech Corp < 85° Test Conditions 1.2V SHDN SHDN V = 0.3V SS ...
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... The exposed pad must be soldered to the ground plane on the PCB for good thermal conduction. Block Diagram IN 6 4.6 A SHDN 3 + CMP - 1.1V VOLTAGE REFERENCE 1.242V + COMP REG_GOOD ENABLE ROSC 7 2005 Semtech Corp. INTERNAL SUPPLY ENABLE THERMAL SHUTDOW N CLK - PWM REG + 1.5 A CLK OSCILLATOR Figure 2. SC4501 (MSOP-8) Block Diagram. 4 SC4501 SW 5 REG I-LIMIT ILIM - ...
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... The exposed pad must be soldered to the ground plane on the PCB for good thermal conduction. Block Diagram IN 8 4.6 A SHDN 3 + CMP - 1.1V VOLTAGE THERMAL REFERENC E SHUTDOWN 1.242V + COMP REG_GOOD ENABL E ROSC 9 2005 Semtech Corp. INTERNAL SUPPLY ENABL E CLK - PWM REG + 1.5 A CLK OSCILLATOR Figure 3. SC4501 (MLPD-10) Block Diagram. 5 SC4501 REG I-LIMIT ILIM - ...
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... Switch Current (A) V Quiescent Current vs Temperature IN 1.3 Not Switching 1 16V IN 1 0.9 0.8 -50 - 100 Temperature (ºC) 2005 Semtech Corp Switching Frequency OSC 100 25º 125 0.0 0.5 1.0 1.5 2.0 Frequency (MHz) Switch Current Limit vs Temperature 3 2.8 2.6 2.4 2.2 2 ...
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... SHDN Voltage (V) Soft-Start Charging Current vs Temperature 0.3V SS 1.8 1.6 1.4 1.2 1 -50 - 100 Temperature (ºC) 2005 Semtech Corp. V Current vs SHDN Pin Voltage IN 0 0.08 0.06 0.04 0. 0.2 0.4 0.6 0.8 1.5 SHDN Voltage (V) Transconductance vs Temperature -50 ...
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... IN the shutdown pin is pulled below 1.1V, the soft-start capacitor is discharged to ground. Pulling the shutdown pin below 0.1V reduces the total supply current 2005 Semtech Corp. Application Information Setting the Output Voltage An external resistive divider R tied to the FB pin (Figure 4) sets the output voltage. ...
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... LIM Inductor Current ON OFF ON DT (1-D)T ON OFF ON OFF Figure 5. Current Waveforms in a Boost Regulator 2005 Semtech Corp worth noting that I V ratio V OUT output current at high frequencies (>1MHz) since switching losses are neglected in its derivation. Nevertheless useful first-order approximation. (3) Using V CESAT ...
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... Although the oscillator is capable of running well above 2MHz, controllability limits the maximum operating frequency. Inductor Selection The inductor ripple current I L operating in continuous-conduction mode is 2005 Semtech Corp MHz . The where f is the switching frequency and L is the inductance. ...
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... RMS current ratings (thus lower 2005 Semtech Corp. forward voltages). This is because the diode conduction interval is much longer than that of the transistor. Converter efficiency will be improved if the voltage drop across the diode is lower ...
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... SC4501 can be used in conjunction with a resistive voltage divider to raise the UVLO threshold and to add an UVLO hysteresis. Figure 7 shows the scheme. Both V V (the desired upper and the lower UVLO threshold L voltages) are determined by the 1.1V threshold crossings, 2005 Semtech Corp. IN SC4501 SHDN IN SC4501 SHDN > ...
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... K HYS HYS 3 C6 Figure 8. Simplified Block Diagram of a Boost Converter 2005 Semtech Corp. The turn off voltage is Frequency Compensation Figure 8 shows the equivalent circuit of a boost converter using the SC4501. The output filter capacitor and the load form an output pole at frequency: ...
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... Transcondu c tan ce GND GND C4 C4 SHDN SHDN SHDN R1 R1 VOUT VOUT Figure 9. Suggested PCB Layout for the SC4501. Notice that there is no via directly under the device. All vias are 12mil in diameter. 2005 Semtech Corp and KHz The poles p 1 Krads ...
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... L1: Cooper-Bussmann SD25-3R3 Figure 10(a). 1.35 MHz All Ceramic Capacitor 3.3V to 12V Boost Converter. Pinout Shown is for MSOP-8 2005 Semtech Corp. the size of the loop formed by these components should be minimized. Since the power switch is integrated inside the SC4501, grounding the output filter capacitor next to ...
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... SHDN 1-CELL C1 SC4501 LI-ION 2 COMP GND ROSC 47nF L1: Sumida CR43 Figure 11(a). 1.2 MHz All Ceramic Capacitor Single Li-ion Cell to 5V Boost Converter. Figure 11(c). Load Transient Response of the Circuit in Figure 2005 Semtech Corp. D1 VOUT 5V, 0.8A 10BQ015 R1 5 301K 100K 17. ...
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... Figure 12(a). 1.5 MHz All Ceramic Capacitor 4-Cell to 5V SEPIC Converter. Pinout Shown is for MSOP-8. V =3. s/div Upper Trace : Output Voltage, AC Coupled, 0.2V/div Lower Trace : Input Inductor Current, 0.2A/div Figure 12(b). Load Transient Response of the Circuit in Figure 12(a switched between 50mA and 350mA LOAD at 1A/ s. 2005 Semtech Corp 4.9 H 2.2 F 10BQ015 ...
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... BAT54S Figure 13(a). 1.5MHz Triple-Output TFT Power Supply. CH4 CH1 CH2 CH3 4ms/div CH1 : OUT1 Voltage, 5V/div CH2 : OUT2 Voltage, 10V/div CH3 : OUT3 Voltage, 5V/div CH4 : Input Voltage, 2V/div Figure 13(b). TFT Power Supply V 2005 Semtech Corp 0 2.2 H 10BQ015 6 ...
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... CH1 CH2 CH3 CH4 4ms/div (b) Figure 14(b) and 14(c). Photo Flash LED Current is Switched Between Torch Mode (0.2A) and Flash Mode (0.7A). Higher LED Current (>0.7A) in Flash Mode is Possible with Fresh Battery. 2005 Semtech Corp. 0.7A (FLASH) 0.2A (TORCH) R6 0.1 R1 698 L1 2 ...
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... OR GATE BURRS. 4. REFERENCE JEDEC STD MO-187, VARIATION AA-T. Land Pattern - MSOP-8L-EDP ( NOTES: 1. THIS LAND PATTERN IS FOR REFERENCE PURPOSES ONLY. CONSULT YOUR MANUFACTURING GROUP TO ENSURE YOUR COMPANY'S MANUFACTURING GUIDELINES ARE MET. 2005 Semtech Corp. e/2 A DIM D MIN NOM MAX MIN .000 A2 .030 b ...
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... CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES). 2. COPLANARITY APPLIES TO THE EXPOSED PAD AS WELL AS TERMINALS. Land Pattern - MLPD-10 3mm H (C) X NOTES: 1. THIS LAND PATTERN IS FOR REFERENCE PURPOSES ONLY. CONSULT YOUR MANUFACTURING GROUP TO ENSURE YOUR COMPANY'S MANUFACTURING GUIDELINES ARE MET. Contact Information 2005 Semtech Corp SEATING PLANE ...