LT3470AIDDB#TRMPBF Linear Technology, LT3470AIDDB#TRMPBF Datasheet
LT3470AIDDB#TRMPBF
Specifications of LT3470AIDDB#TRMPBF
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LT3470AIDDB#TRMPBF Summary of contents
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... The LT3470A has higher output current and improved start-up and dropout performance compared to the LT3470. L, LT, LTC, LTM, Linear Technology, the Linear logo and Burst Mode are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. ...
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LT3470A ABSOLUTE MAXIMUM RATINGS (Note 1) , SHDN Voltage ................................................... 40V V IN BOOST Pin Voltage .................................................. 47V BOOST Pin Above SW Pin ........................................ 25V FB Voltage .................................................................. 5V BIAS Voltage .............................................................15V SW Voltage ................................................................V Maximum Junction Temperature LT3470AE, LT3470AI ...
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ELECTRICAL CHARACTERISTICS l The denotes the specifications which apply over the full operating temperature range, otherwise specifications are 10V 10V 15V, V SHDN IN BOOST BIAS PARAMETER Minimum Input Voltage Quiescent Current ...
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LT3470A TYPICAL PERFORMANCE CHARACTERISTICS Efficiency 3.3V OUT TOKO D52LC 47μ 25° 12V 36V V = 24V ...
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TYPICAL PERFORMANCE CHARACTERISTICS FB Bias Current (V vs Temperature –50 – TEMPERATURE (°C) Switch V (I CESAT vs Temperature 300 250 200 150 100 50 0 –50 – TEMPERATURE ...
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LT3470A TYPICAL PERFORMANCE CHARACTERISTICS Switch V CESAT 700 600 500 400 300 200 100 0 0 100 200 SWITCH CURRENT (mA) Catch Diode Forward Voltage 1.0 0.8 0.6 0.4 0 100 200 CATCH DIODE CURRENT (mA) Minimum Input ...
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PIN FUNCTIONS SHDN (Pin 8): The SHDN pin is used to put the LT3470A in shutdown mode. Tie to ground to shut down the LT3470A. Apply 2V or more for normal operation. If the shutdown feature is not used, tie ...
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LT3470A OPERATION The LT3470A 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 inductor and capacitors. Operation can best be understood by studying the ...
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APPLICATIONS INFORMATION Input Voltage Range The minimum input voltage required to generate a par- ticular output voltage in an LT3470A application is limited by either its 4V undervoltage lockout or by its maximum duty cycle. The duty cycle is the ...
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LT3470A APPLICATIONS INFORMATION 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 Input Capacitor Step-down regulators draw current from the input sup- ply in pulses with very fast rise and ...
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APPLICATIONS INFORMATION Ceramic Capacitors Ceramic capacitors are small, robust and have very low ESR. However, ceramic capacitors can cause problems when used with the LT3470A. Not all ceramic capacitors are suitable. X5R and X7R types are stable over temperature and ...
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LT3470A APPLICATIONS INFORMATION (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 the maximum voltage ratings of ...
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APPLICATIONS INFORMATION 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 input capacitor. The loop formed ...
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... LT3470A. However, these capacitors can cause problems if the LT3470A is plugged into a live supply (see Linear Technology Application Note 88 for a complete discussion). The low loss ceramic capacitor combined with stray inductance in series with the power ...
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APPLICATIONS INFORMATION 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 Prevents Input Voltage Overshoot and ...
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LT3470A APPLICATIONS INFORMATION 4V TO 40V V 5.7V TO 40V 40V 16 3.3V Step-Down Converter 0.22μF , 6.3V V BOOST IN L1 LT3470A 33μH SHDN OFF ON SW BIAS 22pF C1 FB 1μF GND ...
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TYPICAL APPLICATIONS 23V V 15V TO 34V 1.8V Step-Down Converter IN C3 0.22μF , 25V V BOOST IN L1 LT3470A 22μH SHDN OFF ON SW BIAS 22pF C1 FB 1μF GND C1: TDK C3216JB1H105M C2: TDK C2012JB0J226M ...
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LT3470A PACKAGE DESCRIPTION 0.61 ±0.05 (2 SIDES) 0.70 ±0.05 2.55 ±0.05 1.15 ±0.05 0.25 ± 0.05 0.50 BSC 2.20 ±0.05 (2 SIDES) RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS NOTE: 1. DRAWING CONFORMS TO VERSION (WECD-1) IN JEDEC PACKAGE OUTLINE M0-229 ...
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... Added H-grade part information. 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. LT3470A ...
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... I = <1μA, OUT 0.6V 20μ <1μA, OUT 0.8V 60μ <1μA, OUT 0.8V 60μ <1μA, OUT 1.2V 2.5mA 30μA, OUT 1.25V 35μ <1μA, DFN-8, OUT Q SD 3470afb LT 0111 REV B • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2008 ...