SC4502HMLTRT Semtech, SC4502HMLTRT Datasheet
SC4502HMLTRT
Specifications of SC4502HMLTRT
Related parts for SC4502HMLTRT
SC4502HMLTRT Summary of contents
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... Portables devices White LED power supplies D1 VOUT 12V 10BQ015 R1 866K 100K Figure 1(b). Efficiencies 12V Boost Converters at 1 SC4502/SC4502H Regulator with Soft-Start Efficiency 95 10.5 H, 700KHz H, 1.4MHz 2MHz 12V OUT 50 0.0 0.1 0.2 0.3 0.4 0.5 Load Current (A) 700KHz, 1.4MHz and 2MHz. www.semtech.com ...
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... Exceeding the specifications below may result in permanent damage to the device, or device malfunction. Operation outside of the parameters specified in the Electrical Characteristics section is not implied Electrical Characteristics Electrical Characteristics Unless other specified 2V, SHDN = 1.5V 2005 Semtech Corp 7.68k , -40°C < < 85°C OSC ° ° < T < 8 ° < V < SC4502/SC4502H ° C ° ° C ° C ° www.semtech.com ...
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... Pin Configurations TOP VIEW (10 Pin - MLPD 3mm) 2005 Semtech Corp. = 7.68k , -40°C < < 85°C OSC Ordering Information Notes: (1) Only available in tape and reel packaging. A reel contains 3000 devices for MLP package. (2) Lead free product. This product is fully WEEE and RoHS compliant. ...
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... POWER MANAGEMENT Pin Descriptions Block Diagram IN 8 4.6 A SHDN 3 + CMP - 1.1V VOLTAGE REFERENCE 1.242V + COMP REG_GOOD ENABL E ROSC 9 2005 Semtech Corp INTERNAL SUPPLY ENABL E THERMAL SHUTDOWN CLK - PWM REG + 1.5 A CLK OSCILLATOR Figure 2. SC4502/SC4502H Block Diagram. 4 SC4502/SC4502H 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 2.5 Frequency (MHz) Switch Saturation Voltage vs Switch Current 500 SC4502H 400 300 85º ...
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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 0.02 0 1.5 0 0.2 0.4 0.6 0.8 SHDN Voltage (V) Transconductance vs Temperature ...
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... Under fault conditions (V <1.4V or over temperature) or when the shutdown IN 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. SC4502/SC4502H Applications Information Setting the Output Voltage An external resistive divider R and R 1 tied to the FB pin (Figure 3) sets the output voltage ...
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... Inductor Current ON OFF ON DT (1-D)T ON OFF ON OFF Figure 4. Current Waveforms in a Boost Regulator 2005 Semtech Corp worth noting that I ratio of (3) output current at high frequencies (>1MHz) since switching losses are neglected in its derivation. is the D Nevertheless useful first-order approximation. Using V CESAT (4), the maximum output currents for three V combinations are shown in Table 1 ...
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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 2005 Semtech Corp. operating in continuous-conduction mode is 0.25 I 1.67MHz . The L where f is the switching frequency and L is the inductance. ...
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... SC4502/SC4502H. These diodes should have a RMS current rating between 0.5A and 1A with a reverse blocking voltage of at least a few 2005 Semtech Corp. SC4502/SC4502H Volts higher than the output voltage. For switching regulators operating at low duty cycles (i.e. low output ...
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... Switching will stop if V falls below the internal UVLO threshold. The resulting output voltage rise may be non-monotonic. The 1.1V disable threshold of the SC4502/SC4502H can be used 2005 Semtech Corp. IN SC4502 SC4502H SHDN ...
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... HYS 3 The turn off voltage is COMP Figure 7. Simplified Block Diagram of a Boost Converter 2005 Semtech Corp Frequency Compensation Figure 7 shows the equivalent circuit of a boost converter using the SC4502/SC4502H. The output filter capacitor and the load form an output pole at frequency where C ...
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... VOUT VOUT VOUT VOUT Figure 8. Suggested PCB Layout for the SC4502/SC4502H. Notice that there is no via directly under the device. All vias are 12mil in diameter. 2005 Semtech Corp and 3.18KHz The poles p shift in the loop response. For stable operation, the overall 1 loop gain should cross 0dB with -20dB/decade slope ...
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... L1: Sumida CR43 Figure 9(a). 1.35 MHz All Ceramic Capacitor 3.3V to 12V Boost Converter. 2005 Semtech Corp. The input bypass capacitors should also be placed close to the input pins. Shortening the trace at the SW node without reduces the parasitic trace inductance. This not only ...
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... SHDN 1-CELL C1 SC4502 LI-ION 2 GND ROSC C3 4,5 47nF L1: Sumida CDRH5D28 Figure 10(a). 1.5 MHz All Ceramic Capacitor Single Li-ion Cell to 5V Boost Converter. Figure 10(c). Load Transient Response of the Circuit in Figure . 2005 Semtech Corp. D1 VOUT 5V, 0.5A 10BQ015 R1 6,7 301K COMP R2 R3 100K 34 ...
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... Figure 11(a). 1.5 MHz All Ceramic Capacitor 4-Cell to 5V SEPIC Converter. 40 s/div Upper Trace : Output Voltage, AC Coupled, 0.5V/div Lower Trace : Input Inductor Current, 0.2A/div Figure 11(b). Load Transient Response of the Circuit in Figure 11(a switched between 150mA and LOAD 450mA at 1A/ s. 2005 Semtech Corp 3 ...
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... C1 2 100K L1 : Coiltronics SD18-3R3 BAT54S Figure 12(a). 1.5MHz Triple-Output TFT Power Supply 4ms/div CH1 : OUT1 Voltage, 5V/div CH2 : OUT2 Voltage, 10V/div CH3 : OUT3 Voltage, 5V/div CH4 : Input Voltage, 2V/div Figure 12(b). TFT Power Supply V 2005 Semtech Corp 0 3.3 H 10BQ015 8 6 SHDN FB ...
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... OFF ON SHDN FB C1 SC4502H 2.2µ COMP GND ROSC C3 9 4,5 47nF R4 Figure 13(a). All Ceramic Capacitor High Voltage Application 2005 Semtech Corp. D1 VOUT 90 35V 85 SS14 R1 17. 10µ 5.11K 649 1.5nF 50 Figure 13(b). Efficiency of the All Ceramic Capacitor High ...
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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 DIM ...