SC4502H Semtech Corporation, SC4502H Datasheet
SC4502H
Related parts for SC4502H
SC4502H Summary of contents
Page 1
... Programmable soft-start eliminates high inrush current during start-up. The inter- nal switch is rated at 32V (40V for the SC4502H) mak- ing the converter suitable for high voltage applications such as Boost, SEPIC and Flyback. ...
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... SC4502/SC4502H ...
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... 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. 3 SC4502/SC4502H ...
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... INTERNAL SUPPLY ENABL E THERMAL SHUTDOWN CLK - PWM REG + 1.5 A CLK OSCILLATOR Figure 2. SC4502/SC4502H Block Diagram. 4 SC4502/SC4502H ...
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... Switch Current (A) V Current in Shutdown IN vs Input Voltage 50 40 -40ºC 30 125º SHDN 0 125 Input Voltage (V) 5 SC4502/SC4502H Switching Frequency vs Temperature 1.7 R OSC 1 12V IN 1 1.4 1.3 -50 - 3.0 Temperature (ºC) Minimum V vs Temperature IN 1.5 1.4 1.3 1.2 1 ...
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... 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 125 -50 - Temperature (ºC) 6 SC4502/SC4502H Shutdown Pin Current vs Temperature -3 V 25º 12V 1.2 -50 - Temperature (ºC) Switch Current Limit vs Temperature 2 2.2 2 1.8 1.6 -50 - ...
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... The SC4502/SC4502H requires a minimum input of 1.4V to operate. A voltage higher than 1.1V at the shutdown pin enables the internal linear regulator REG in the SC4502/SC4502H. After V ...
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... Regulator closed-loop measurement shows that the SC4502/SC4502H has a minimum on time of about 150ns at room temperature. The power switch in the SC4502/SC4502H is either not I IN turned on at all or on for at least 150ns. If the required switch on time is shorter than the minimum on time, the regulator will either skip cycles or it will start to jitter ...
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... A regulator in dropout may appear current limit. The cycle-by-cycle current limit of the SC4502/SC4502H is duty-cycle and input voltage invariant and is typically 2A. If the switch current limit is not at least 1.4A, then the converter is likely in dropout ...
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... Shutdown (9) The input voltage and shutdown pin voltage must be greater than 1.4V and 1.1V respectively to enable the SC4502/ SC4502H. Forcing the shutdown pin below 1.1V stops the SC4502/SC4502H from switching. Pulling this pin below 0.1V completely shuts off the SC4502/SC4502H. The total V shutdown current decreases to 10µA at 2V. ...
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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 ...
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... 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 the equivalent load resistance. ...
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... SHDN SHDN SHDN 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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... For jitter-free operation, the size of the loop formed by these components should be minimized. Since the power switch is integrated inside the SC4502/SC4502H, grounding the output filter capacitor next to the SC4502/SC4502H ground pin minimizes size of the high di/dt current loop. Typical Application Circuits L1 VIN 5 ...
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... Figure 10(b). Efficiency of the Single Li-ion Cell to 5V Boost V =2. s/div Upper Trace : Output Voltage, AC Coupled, 0.5V/div Lower Trace : Inductor Current, 0.5A/div 10(a switched between 90mA and 0.5A LOAD at 1A SC4502/SC4502H Efficiency vs Load Current 95 90 1.5MHz 4. 3. ...
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... ROSC 35.7K C3 4,5 9 47nF R4 C4 7.68K 1.5nF L1 and L2: Coiltronics DRQ73-3R3 V =3.6V IN Upper Trace : Output Voltage, AC Coupled, 0.5V/div Lower Trace : Input Inductor Current, 0.2A/div Figure 11(c). Load Transient Response of the Circuit in Figure 16 SC4502/SC4502H VOUT D1 5V, 0.5A 10BQ015 R1 60. 3.3 H 20K C6 22pF V = s/div 11(a) ...
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... COMP 0 GND ROSC 33.2K C3 4,5 9 47nF R4 C4 7.68K 1.5nF D7 D6 Figure 12(c). TFT Power Supply Start-up Transient as the Start-up Transient SC4502/SC4502H D4 D5 OUT2 23V (10mA 0 OUT1 8V (0.4A) R1 274K 49.9K OUT3 -8V (10mA) C10 ...
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... R3 R2 5.11K 649 1.5nF 50 Figure 13(b). Efficiency of the All Ceramic Capacitor High SC4502/SC4502H Efficiency at 14V input 1.4MHz 6.8 H 1.0MHz 0.05 0.1 0.15 Load (A) Voltage Application 0.2 www.semtech.com ...
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... DIM INCHES Semtech Corporation Power Management Products Division 200 Flynn Road, Camarillo, CA 93012 Phone: (805)498-2111 FAX (805)498-3804 19 SC4502/SC4502H DIMENSIONS INCHES MILLIMETERS MIN NOM MAX MIN NOM MAX - - .031 .039 0.80 1. .000 .002 0.00 0.05 - (.008) ...