LT3503EDCB#TRMPBF Linear Technology, LT3503EDCB#TRMPBF Datasheet
LT3503EDCB#TRMPBF
Specifications of LT3503EDCB#TRMPBF
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LT3503EDCB#TRMPBF 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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LT3503 ABSOLUTE AXI U RATI GS (Note 1) Input Voltage (V ) .................................................. 20V IN BOOST Pin Voltage .................................................. 40V BOOST Pin Above SW Pin ....................................... 20V SHDN Pin ................................................................ 20V FB Voltage ................................................................. 6V Operating Temperature ...
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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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... Figure 10. A Well Chosen Input Network Prevents Input Voltage Overshoot and Ensures Reliable Operation When the LT3503 is Connected to a Live Supply live supply (see Linear Technology Application Note 88 for a complete discussion). The low loss ceramic capaci- tor combined with stray inductance in series with the V ...
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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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... For outputs greater than 6V, add a resistor 2.5k across the inductor to damp the discontinuous ringing of the SW node, preventing unintended SW current. Other Linear Technology Publications Application notes AN19, AN35 and AN44 contain more detailed descriptions and design information for Buck regulators and other switching regulators. The LT1376 data sheet has a more extensive discussion of output ripple, loop compensation and stability testing ...
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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 ● ...