SC4518HSETRT Semtech, SC4518HSETRT Datasheet
SC4518HSETRT
Specifications of SC4518HSETRT
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SC4518HSETRT Summary of contents
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... Synchronizable to higher frequency up to 1.2MHz Precision enable threshold SO-8 EDP package. Lead free product, fully WEEE and RoHS compliant Applications XDSL modems CPE equipment DC-DC point of load applications Portable equipment BST SC4518H SYNC COMP D2 GND SC4518H 600kHz, 2A Step-Down Switching Regulator VOUT www.semtech.com ...
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... Notes: (1) For proper operation of device, V Characteristics. (2) Minimum pad size. Electrical Characteristics Unless specified 12V 0.8V COMP BST -40°C to 125° 2007 Semtech Corp should be within maximum Operating Input Voltage as defined in Electrical 5V tied SYNC = open ° SC4518H www.semtech.com ° ° C ° C ° ...
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... POWER MANAGEMENT Electrical Characteristics (Cont.) Unless specified 12V 0.8V COMP BST -40°C to 125° 2007 Semtech Corp 5V tied SYNC = open < V < µ SC4518H www.semtech.com µ µ µ µ ...
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... Notes: (1) The device may not function properly outside its operating input voltage. (2) The required input voltage for a regulated output depends on the output voltage and load condition. (3) Guaranteed by design. (4) Please contact factory for SYNC applications. 2007 Semtech Corp 5V tied SYNC = open ...
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... Pin Configurations TOP VIEW BST GND 4 5 (SO-8 EDP) Pin Descriptions 2007 Semtech Corp. Ordering Information SYNC S C COMP Notes: (1) Only available in tape and reel packaging. A reel FB contains 2500 devices. EN (2) Lead free product. This product is fully WEEE and RoHS compliant ...
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... POWER MANAGEMENT Block Diagram COMP COMP - - SYNC SYNC OSCILLATOR OSCILLATOR Typical Characteristic - OCP Limit 4.5 4 3.5 3 2.5 2 1 2007 Semtech Corp ISEN ISEN + + SLOPE SLOPE + + PWM PWM UVLO UVLO REFERENCE REFERENCE SOFT START SOFT START HICCUP HICCUP 0.7V 0.7V SLOPE ...
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... Figure 1 shows the voltage on COMP during a sustained overcurrent condition. Figure 1. Voltage on COMP for Startup and OCP 2007 Semtech Corp. Enable Pulling and holding the EN pin below 0.4V activates the shut down mode of the SC4518H which reduces the input supply current to less than 150µA. During the shut down mode, the switch is turned off ...
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... V = output voltage. O The peak to peak inductor current is: 2007 Semtech Corp. After the required inductor value is selected, the proper selection of the core material is based on the peak inductor current and efficiency specifications. The core Vo=2.5V must be able to handle the peak inductor current I Vo=3 ...
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... The worst case conduction time T estimated as follows max f s Where the switching frequency and s Dmax = maximum duty ratio, 0.85 for the SC4518H. 2007 Semtech Corp. The required minimum capacitance for the boost capacitor will be: Where the boost current and discharge ripple voltage. D With f = 600kHz ...
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... Where: R – Load and L C – Output capacitor. 2007 Semtech Corp. The goal of the compensation design is to shape the loop to have a high DC gain, high bandwidth, enough phase margin, and high attenuation for high frequency noises. Figure 3 gives a typical compensation network which ...
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... P2 s the switching ripple and high frequency noise with the adequate phase lag at C. 2007 Semtech Corp. Layout Guidelines: In order to achieve optimal electrical and thermal performance for high frequency converters, special attention must be paid to the PCB layouts. The goal of layout optimization is to identify the high di/dt loops and minimize them ...
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... 4.75k 4.75k 4.75k 4.75k 4.75k 10u 10u 10u 10u 10u Bill of Materials 2007 Semtech Corp SYNC SYNC SYNC SYNC SYNC SYNC COMP COMP COMP COMP COMP COMP SC4518H SC4518 SC4518 SC4518 SC4518H SC4518H 180p 180p 180p 180p 180p ...
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... POWER MANAGEMENT Application Information (Cont.) (COMPONENT - TOP) (PCB - TOP) 2007 Semtech Corp. (COMPONENT - BOTTOM) (PCB - BOTTOM) 13 SC4518H SC4518H 8 8 www.semtech.com ...
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... Outline Drawing - SOIC-8L EDP 2X ccc C 2X N/2 TIPS aaa C SEATING PLANE EXPOSED PAD NOTES: 1. CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES). 2. DATUMS -A- 3. DIMENSIONS "E1" AND "D" DO NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS. 4. REFERENCE JEDEC STD MS-012, VARIATION BA. 2007 Semtech Corp DIM A E ...
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... COMPANY'S MANUFACTURING GUIDELINES ARE MET. 2. REFERENCE IPC-SM-782A, RLP NO. 300A. 3. 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. Contact Information Phone: (805)498-2111 FAX (805)498-3804 2007 Semtech Corp. E SOLDER MASK D DIM ...