lt3503edcb-trpbf Linear Technology Corporation, lt3503edcb-trpbf Datasheet
lt3503edcb-trpbf
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lt3503edcb-trpbf Summary of contents
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... The low current (<2µA) shutdown mode provides output disconnect, enabling easy power management in battery-powered systems. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. V OUT 3 ...
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... BOOST 6-LEAD (2mm 3mm) PLASTIC DFN EXPOSED PAD (PIN 7) IS GND, MUST BE SOLDERED TO PCB ORDER PART NUMBER LT3503EDCB Order Options Tape and Reel: Add #TR Lead Free: Add #PBF Lead Free Tape and Reel: Add #TRPBF Lead Free Part Marking: Consult LTC Marketing for parts specified with wider operating temperature ranges. ...
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ELECTRICAL CHARACTERISTICS The ● denotes specifications which apply over the full operating temperature range, otherwise specifications are 12V 17V, unless otherwise noted. (Note 2) IN BOOST PARAMETER Switch Current Limit Switch V CESAT Switch ...
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LT3503 W U TYPICAL PERFOR A CE CHARACTERISTICS Maximum Load Current 1 3.3V OUT L = 2.2µH 1.6 TYPICAL 1.4 1.2 MINIMUM 1.0 0.8 0.6 0.4 0 INPUT VOLTAGE ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS SHDN Pin Current (V) SHDN 3503 G12 Switch Current Limit ...
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LT3503 CTIO S FB (Pin 1): The LT3503 regulates its feedback pin to 780mV. Connect the feedback resistor divider tap to this pin. Set the output voltage according to: ⎛ ⎞ OUT R ...
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U OPERATIO (Refer to Block Diagram) The LT3503 is a constant frequency, current mode step- down regulator. A 2.2MHz oscillator enables an RS flip- flop, turning on the internal 1.75A power switch Q1. An amplifier and comparator monitor the current ...
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LT3503 U U APPLICATIO S I FOR ATIO FB Resistor Network The output voltage is programmed with a resistor divider between the output and the FB pin. Choose the 1% resistors according to: ⎛ ⎞ OUT ⎝ ⎜ ...
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U U APPLICATIO S I FOR ATIO Now the required on time has decreased below the mini- mum on time of 130ns. Instead of the switch pulse width becoming narrower to accommodate the lower duty cycle requirement, the switch pulse ...
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LT3503 U U APPLICATIO S I FOR ATIO Table 1. Inductor Vendors Vendor URL Sumida www.sumida.com Toko www.toko.com Würth Elektronik www.we-online.com transient response. If your load is lower than 1A, then you can decrease the value of the inductor and ...
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U U APPLICATIO S I FOR ATIO Ceramic capacitors have very low equivalent series resis- tance (ESR) and provide the best ripple performance. A good value is 24/V OUT OUT is in µF. Use X5R or X7R types ...
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LT3503 U U APPLICATIO S I FOR ATIO 36.5k FB 11.3k 36.5k 1nF FB 11.3k 36.5k 1nF + FB 11.3k Figure 5. Transient Load Response of the LT3503 with Different Output Capacitors as the Load Current is Stepped from 0.5A ...
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U U APPLICATIO S I FOR ATIO BOOST LT3503 GND ≅ – V BOOST SW OUT ≅ V MAX BOOST IN OUT (6a) 7.7 7.2 TO START 6.7 TO RUN ...
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LT3503 U U APPLICATIO S I FOR ATIO Soft-Start The SHDN pin can be used to soft-start the LT3503, reducing the maximum input current during start-up. The SHDN pin is driven through an external RC filter to create a voltage ...
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U U APPLICATIO S I FOR ATIO BOOST IN IN LT3503 SHDN SW GND FB Figure 9. Diode D4 Prevents a Shorted Input from Discharging a Backup Battery Tied to the Output; It Also Protects the Circuit ...
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LT3503 U U APPLICATIO S I FOR ATIO damps the circuit and eliminates the voltage overshoot. The extra capacitor improves low frequency ripple filtering and can slightly improve the efficiency of the circuit, though it is likely to be the ...
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U U APPLICATIO S I FOR ATIO V IN SHUTDOWN Figure 12. A Good PCB Layout Ensures Proper, Low EMI Operation local, unbroken ground plane below these components, and tie this ground plane to system ground at one location, ideally ...
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LT3503 U TYPICAL APPLICATIO S 3. 20V MAX ON OFF V IN 3.6V TO 7.6V 20V MAX ON OFF V IN 3.6V TO 10V 20V MAX ON OFF 18 0.78V Step-Down Converter BAT54 BOOST IN ...
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... NOTE 6) 0.200 REF Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. U DCB Package 6-Lead Plastic DFN (2mm × ...
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... OUT DC/DC Converter LT3506/LT3506A Dual 25V, 1. 575kHz/1.1MHz High Efficiency OUT Step-Down DC/DC Converter Burst Mode is a registered trademark of Linear Technology Corporation. ThinSOT is a trademark of Linear Technology Corporation. Linear Technology Corporation 20 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● 5V Step-Down Converter ...