SC4518H Semtech Corporation, SC4518H Datasheet
SC4518H
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SC4518H Summary of contents
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... POWER MANAGEMENT Description The SC4518H is a current mode switching regulator with an integrated switch, operating at 600kHz with separate sync and enable functions. The integrated switch allows for cost effective low power solutions (peak switch current 2 amps). The sync function allows customers to synchronize to a faster clock in order to avoid frequency beating in noise sensitive applications ...
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... SC4518H ° ° C ° C ° C ° ...
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... SC4518H µ µ µ µ ...
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... SC4518H µ A µ www.semtech.com ...
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... SC4518H ...
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... UVLO UVLO REFERENCE REFERENCE SOFT START SOFT START HICCUP HICCUP 0.7V 0.7V SLOPE SLOPE SLOPE COMP SLOPE COMP OSCILLATOR OSCILLATOR CLK CLK FREQUENCY FREQUENCY SC4518H OCP Limit vs Duty Cycle Duty Cycle (%) 6 SC4518H + + IN IN ISEN ISEN 40m 40m BST BST POWER POWER TRANSISTOR ...
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... UVLO When the EN pin is pulled and held above 1.8V, the voltage on Pin IN determines the operation of the SC4518H. As VIN increases during power up, the internal circuit senses VIN and keeps the power transistor off until VIN reaches 4 ...
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... The first one is the required ESR (Equivalent Series Resistance) which should be low enough to reduce the output voltage deviation during load changes. The second one is the required capacitance, which should be high enough to hold up the output voltage. Before the SC4518H regulates the inductor current to a new value ( ...
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... Its maximum repetitive reverse block voltage has to be higher than the input voltage of the SC4518H. A low forward conduction drop is also required to increase the overall efficiency. The freewheeling diode should be ...
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... P V diode Loop Compensation Design The SC4518H has an internal error amplifier and requires a compensation network to connect between the COMP pin and GND pin as shown in Figure 3. The compensation network includes C4, C5 and R3. R1 and R2 are used to program the output voltage according to: ...
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... Connect the ground of the feedback divider and the compensation components directly to the GND pin of the SC4518H by using a separate ground trace. IC heat and increase the power capability of the SC4518H. A few feedthrough holes are required to connect this large copper area to a ground plane to further improve the thermal environment of the SC4518H ...
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... SC4518H =5V =5V =5V =5V = 47u 47u 47u 47u 47u 47u / . ...
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... POWER MANAGEMENT Application Information (Cont.) (COMPONENT - TOP) www.DataSheet4U.com (PCB - TOP) 2007 Semtech Corp. (COMPONENT - BOTTOM) (PCB - BOTTOM) 13 SC4518H 8 8 SC4518H www.semtech.com ...
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... BSC e .050 BSC 1.27 BSC F .116 .120 .130 2.95 3.05 3.30 .085 .095 .099 2.15 2. .010 .020 0.25 0.50 L .016 .028 .041 0.40 0.72 1.04 (.041) (1.05 0° 8° 0° 8° aaa .004 0.10 bbb .010 0.25 ccc .008 0. GAGE PLANE 0. (L1) A DETAIL A SEE DETAIL -H- SC4518H www.semtech.com ...
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... THERMAL VIAS IN THE LAND PATTERN OF THE EXPOSED PAD SHALL BE CONNECTED TO A SYSTEM GROUND PLANE. FAILURE MAY COMPROMISE THE THERMAL AND/OR FUNCTIONAL PERFORMANCE OF THE DEVICE. Semtech Corporation Power Management Products Division 200 Flynn Road, Camarillo, CA 93012 Phone: (805)498-2111 FAX (805)498-3804 15 SC4518H DIMENSIONS DIM INCHES MILLIMETERS (.205) (5.20 ...