LT3493EDCB#PBF Linear Technology, LT3493EDCB#PBF Datasheet
LT3493EDCB#PBF
Specifications of LT3493EDCB#PBF
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LT3493EDCB#PBF Summary of contents
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... The low current (<2μA) shutdown mode provides output disconnect, enabling easy power management in battery-powered systems. L, 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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... LT3493E .............................................. –40°C to 85°C LT3493I ............................................. –40°C to 125°C Maximum Junction Temperature .......................... 125°C Storage Temperature Range ................... –65°C to 150°C ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL LT3493EDCB#PBF LT3493EDCB#TRPBF LT3493IDCB#PBF LT3493IDCB#TRPBF LEAD BASED FINISH TAPE AND REEL LT3493EDCB ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T PARAMETER Switch Current Limit Switch V CESAT Switch Leakage Current Minimum Boost Voltage Above Switch BOOST Pin Current SHDN Input Voltage High SHDN Input Voltage Low SHDN Bias Current Note ...
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LT3493 TYPICAL PERFORMANCE CHARACTERISTICS Maximum Load Current 5V 8.2μH OUT 1.60 1.50 TYPICAL 1.40 1.30 1.20 MINIMUM 1.10 1.00 0. (V) IN 3493 G04 Maximum Load Current ...
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TYPICAL PERFORMANCE CHARACTERISTICS SHDN Pin Current (V) SHDN 3493 G14 Switch Current Limit 2.0 1.9 1.8 1.7 1.6 ...
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LT3493 PIN FUNCTIONS FB (Pin 1): The LT3493 regulates its feedback pin to 780mV. Connect the feedback resistor divider tap to this pin. Set the output voltage according R1/R2). A good value for R2 is 10k. ...
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OPERATION (Refer to Block Diagram) The LT3493 is a constant frequency, current mode step- down regulator. A 750kHz oscillator enables an RS fl ip-fl op, turning on the internal 1.75A power switch Q1. An amplifi er and comparator monitor the ...
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LT3493 APPLICATIONS INFORMATION FB Resistor Network The output voltage is programmed with a resistor divider between the output and the FB pin. Choose the 1% resis- tors according to: V OUT R1= R2 – 1 0.78V R2 should be 20k ...
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... Low inductance may result in discontinuous mode operation, which is okay, but further reduces maximum load current. For details of the maximum output current and discontinuous mode operation, see Linear Technology Application Note 44. Catch Diode Depending on load current Schottky diode is recommended for the catch diode, D1 ...
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LT3493 APPLICATIONS INFORMATION Table 1. Inductor Values VENDOR URL Sumida www.sumida.com Toko www.toko.com Würth Elektronik www.we-online.com Input Capacitor Bypass the input of the LT3493 circuit with a 1μF or higher value ceramic capacitor of X7R or X5R type. Y5V types ...
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APPLICATIONS INFORMATION Table 2. Capacitor Vendors VENDOR Panasonic Kemet Sanyo Murata AVX Taiyo Yuden capacitor must be large to achieve low ESR. Table 2 lists several capacitor vendors. Figure 4 shows the transient response of the LT3493 with several output ...
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LT3493 APPLICATIONS INFORMATION 32.4k FB 10k 32.4k 3.3nF FB 10k 32. 10k Figure 4. Transient Load Response of the LT3493 With Different Output Capacitors as the Load Current is Stepped from 250mA to 1A BOOST LT3493 ...
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... The small size, robustness and low impedance of ceramic capacitors make them an attractive option for the input bypass capacitor of LT3493 circuits. However, these capaci- tors can cause problems if the LT3493 is plugged into a live supply (see Linear Technology Application Note 88 for LT3493 TO START TO RUN ...
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LT3493 APPLICATIONS INFORMATION SHDN RUN GND 3493 F07a RUN 15k SHDN 0.1μF GND 3493 F07b Figure 7. To Soft-Start the LT3493, Add a Resistor and Capacitor to the SHDN Pin BOOST IN IN LT3493 SHDN SW ...
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APPLICATIONS INFORMATION a 2.2μF ceramic capacitor at the input. The input voltage rings as high as 35V and the input current peaks at 20A. One method of damping the tank circuit is to add another capacitor with a series resistor ...
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LT3493 APPLICATIONS INFORMATION model works well as long as the value of the inductor is not too high and the loop crossover frequency is much lower than the switching frequency. With a larger ceramic capacitor (very low ESR), crossover may ...
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... BOOST pin. The 12V circuit shows how to overcome this limitation using an additional zener diode. 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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LT3493 TYPICAL APPLICATIONS V IN 3.6V TO 28V ON OFF V IN 4.2V TO 36V ON OFF V IN 6.4V TO 36V ON OFF 18 2.5V Step-Down Converter BAT54 V BOOST IN 0.47μF 6.8μH LT3493 SHDN SW 22.1k MBRM140 GND ...
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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 representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. DCB Package 6-Lead Plastic DFN (2mm × ...
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... I , 200kHz/500kHz, High Effi ciency Step-Down OUT DC/DC Converter LT3470 40V, 200mA I , 26μA I OUT Burst Mode is a registered trademark of Linear Technology Corporation. Linear Technology Corporation 20 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● 12V Step-Down Converter ...