lt3470its8-trpbf Linear Technology Corporation, lt3470its8-trpbf Datasheet
lt3470its8-trpbf
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lt3470its8-trpbf Summary of contents
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... LT3470 and external components against shorted out- puts, even at 40V input. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. Burst Mode is a registered trademark of Linear Technology Corporation. ThinSOT is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. 0.22µF 33µH ...
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... LT3470EDDB LT3470EDDB#TR LT3470IDDB LT3470EDDB#TR LT3470HDDB LT3470EDDB#TR LT3470ETS8 LT3470ETS8#TR LT3470ITS8 LT3470ITS8#TR LT3470HTS8 LT3470HTS8#TR Consult LTC Marketing for parts specified with wider operating temperature ranges. For more information on lead free part marking, go to: For more information on tape and reel specifications (Note 1) LT3470H .......................................................... 150° ...
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ELECTRICAL CHARACTERISTICS The ● denotes specifications which apply over the full operating temperature range, otherwise specifications are 10V 10V 15V SHDN BOOST PARAMETER Minimum Input Voltage Quiescent Current from V IN ...
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LT3470 W U TYPICAL PERFOR A CE CHARACTERISTICS Efficiency 3.3V OUT TOKO D52LC 47µ 25° 12V 24V V = 36V IN ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS FB Bias Current ( Temperature 120 100 100 125 150 –50 – TEMPERATURE (°C) 3470 G09 Catch Diode V (I ...
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LT3470 W U TYPICAL PERFOR A CE CHARACTERISTICS Boost Diode Forward Voltage 900 800 700 600 500 400 300 200 100 100 150 200 BOOST DIODE CURRENT (mA) 3470 G17 CTIO S ...
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W BLOCK DIAGRA 500ns ONE SHOT NC SHDN V REF 1.25V – R Q′ – ENABLE + BURST MODE DETECT LT3470 BIAS BOOST ...
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LT3470 U OPERATIO The LT3470 uses a hysteretic control scheme in conjunc- tion with Burst Mode operation to provide low output ripple and low quiescent current while using a tiny induc- tor and capacitors. Operation can best be understood by ...
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U U APPLICATIO S I FOR ATIO Input Voltage Range The minimum input voltage required to generate a particu- lar output voltage in an LT3470 application is limited by either its 4V undervoltage lockout or by its maximum duty cycle. ...
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LT3470 U U APPLICATIO S I FOR ATIO Table 2. Inductor Vendors VENDOR URL Coilcraft www.coilcraft.com Sumida www.sumida.com Toko www.tokoam.com Würth Elektronik www.we-online.com Coiltronics www.cooperet.com Murata www.murata.com be used important to note that inductor saturation current is reduced ...
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U U APPLICATIO S I FOR ATIO Ceramic Capacitors Ceramic capacitors are small, robust and have very low ESR. However, ceramic capacitors can cause problems when used with the LT3470. Not all ceramic capacitors are suitable. X5R and X7R types ...
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LT3470 U U APPLICATIO S I FOR ATIO (Figure 2b). The circuit in Figure 2a is more efficient because the BOOST pin current and BIAS pin quiescent current comes from a lower voltage source. You must also be sure that ...
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U U APPLICATIO S I FOR ATIO PCB Layout For proper operation and minimum EMI, care must be taken during printed circuit board layout. Note that large, switched currents flow in the power switch, the internal catch diode and the ...
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LT3470 U U APPLICATIO S I FOR ATIO Hot-Plugging Safely The small size, robustness and low impedance of ceramic capacitors make them an attractive option for the input bypass capacitor of LT3470. However, these capacitors can cause problems if the ...
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U U APPLICATIO S I FOR ATIO CLOSING SWITCH SIMULATES HOT PLUG + LOW STRAY IMPEDANCE INDUCTANCE ENERGIZED DUE TO 6 FEET 24V SUPPLY (2 METERS) OF TWISTED PAIR 10µF 35V AI.EI. 0.1µF Figure 6: A Well Chosen Input Network ...
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LT3470 U TYPICAL APPLICATIO S 5.5V TO 40V 40V 4.7V TO 40V 16 3.3V Step-Down Converter 0.22µF, 6.3V V BOOST IN L1 LT3470 33µH OFF ON SHDN SW BIAS 22pF C1 FB 1µF ...
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U TYPICAL APPLICATIO 23V V IN 15V TO 34V 1.8V Step-Down Converter C3 0.22µF, 25V V BOOST IN L1 LT3470 22µH OFF ON SHDN SW R1 BIAS 22pF 147k C1 FB 1µF GND R2 332k ...
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LT3470 PACKAGE DESCRIPTIO 0.52 MAX 3.85 MAX 2.62 REF RECOMMENDED SOLDER PAD LAYOUT PER IPC CALCULATOR 0.20 BSC DATUM ‘A’ 0.30 – 0.50 REF NOTE: 1. DIMENSIONS ARE IN MILLIMETERS 2. DRAWING NOT TO SCALE 3. DIMENSIONS ARE INCLUSIVE OF ...
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... SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE TOP AND BOTTOM OF PACKAGE 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. ...
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... OUT 0.8V 20µ <1µA, OUT 0.6V 20µ <1µA, OUT 0.8V 60µ <1µA, OUT 0.8V 60µ <1µA, OUT 1.2V 2.5mA 30µA, OUT Q SD 3470fc LT 0907 REV C • PRINTED IN THE USA © LINEAR TECHNOLOGY CORPORATION 2004 ...