SC4525CSETRT Semtech, SC4525CSETRT Datasheet

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POWER MANAGEMENT Features Wide input range 28V  3A Output Current  200kHz to 2MHz Programmable Frequency  Precision 1V Feedback Voltage  Peak Current-Mode Control  Cycle-by-Cycle Current Limiting  Hiccup Overload Protection with Frequency Foldback  ...

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... GND Pin SOIC - EDP) Marking Information yyww=Date code (Example: 0752) xxxxx=Semtech Lot No. (Example: E9010) Ordering Information Device SC4525CSETRT BST SC4525CEVB FB Notes: COMP (1) Available in tape and reel only. A reel contains 2,500 devices. (2) Available in lead-free package only. Device is fully WEEE and RoHS SS/EN compliant and halogen-free ...

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Absolute Maximum Ratings V Supply Voltage ……………………………… -0.3 to 32V IN BST Voltage ……………………………………………… 42V BST Voltage above SW …………………………………… 34V SS Voltage ……………………………………………-0 Voltage …………………………………………… -0 Voltage ………………………………………… -0 Transient ...

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Electrical Characteristics (Cont.) Unless otherwise noted 12V 15V BST Parameter Minimum Switch On-time Minimum Switch Off-time Switch Leakage Current Minimum Bootstrap Voltage BST Pin Current Oscillator Switching Frequency Foldback Frequency Soft Start and Overload ...

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Pin Descriptions SO-8 Pin Name Pin Function Emitter of the internal NPN power transistor. Connect this pin to the inductor, the freewheeling diode and the 1 SW bootstrap capacitor. Power supply to the regulator also the collector of ...

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Block Diagram COMP FREQUENCY FOLDBACK ROSC OSCILLATOR SS/ 1.9V REFERENCE & THERMAL SHUTDOWN SS/EN SS/EN FAULT FAULT Figure 3. Soft-start and Overload Hiccup Control Circuit ...

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Eff Typical Characteristics Efficiency =3. =2. =1. 1MHz, V =12V Curve =B320A 0.5 ...

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Curve 11 Typical Characteristics (Cont.) SS270 REV 6-7 V Thresholds vs Temperature IN 3.0 2.9 Start 2.8 2.7 2.6 Curve 14 UVLO 2.5 2.4 -50 - Temperature ( SS270 REV 6-7 V Quiescent Current vs V ...

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Applications Information Operation The SC4525C is a constant-frequency, peak current-mode, step-down switching regulator with an integrated 28V, 3.9A power NPN transistor. Programmable switching frequency makes the regulator design more flexible. With the peak current-mode control, the double reactive poles of ...

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Applications Information (Cont.) becomes armed. As the load draws more current from the regulator, the current-limit comparator ILIM (Figure 2) will eventually limit the switch current on a cycle-by- cycle basis. The over-current signal OC goes high, setting the latch ...

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Applications Information (Cont.) Closed-loop measurement shows that the SC4525C minimum on time is about 120ns at room temperature (Figure 4). If the required switch on time is shorter than the minimum on time, the regulator will either skip cycles or ...

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Applications Information (Cont.) resulting in very low ripple current. Avoid using Z5U and Y5V ceramic capacitors for output filtering because these types of capacitors have high temperature and high voltage coefficients. Freewheeling Diode Use of Schottky barrier diodes as freewheeling ...

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Applications Information (Cont     − − BST   − − ...

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Applications Information (Cont.) The high frequency pole nulls the ESR zero and attenuates high frequency noise Fz1 Fz1 -30 -30 -60 - 10K 10K 100K 100K FREQUENCY (Hz) ...

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Applications Information (Cont.) Table 4. Typical switching time Input Voltage Input Voltage 1A 1A 12V 12V 12.5ns 12.5ns 24V 24V 22ns 22ns 28V 28V 25.3ns 25.3ns + + addition, the quiescent current loss is BST ...

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Recommended Component Parameters in Typical Applications Table 5 lists the recommended inductance (L voltages. The inductance is determined by assuming that the ripple current is 35% of load current I parameters are calculated by assuming a 47mF low ESR ceramic ...

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Typical Application Schematics 24V 4.7mF Coiltronics DR74- 6R8 Figure 10. 300kHz 24V to 1.5V/3A Step-down Converter 10V – 26V 4.7m F Fig10 : 300 kHz 1.5V/3 ...

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Typical Performance Characteristics (For A 12V to 5V/3A Step-down Converter with 1MHz Switching Frequency) SS270 REV 6-7 Load Characteristic 0.5 1 1.5 2 2.5 Load Current (A) Figure 12(a). Load Characteristic 5V ...

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Outline Drawing - SOIC-8 EDP N 2X E/2 1 ccc C 2X N/2 TIPS aaa C SEATING PLANE C EXPOSED PAD NOTES: 1. CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES). 2. DATUMS -A- AND 3. DIMENSIONS "E1" AND "D" ...

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Land Pattern - SOIC-8 EDP (C) F THERMAL VIA P Ø 0.36mm NOTES: 1. THIS LAND PATTERN IS FOR REFERENCE PURPOSES ONLY. CONSULT YOUR MANUFACTURING GROUP TO ENSURE YOUR COMPANY'S MANUFACTURING GUIDELINES ARE MET. 2. REFERENCE IPC-SM-782A, RLP NO. 300A. ...

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