LT3480IMSE Linear Technology Corporation, LT3480IMSE Datasheet
LT3480IMSE
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LT3480IMSE Summary of contents
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... The LT3480 is available in 10-Pin MSOP and 3mm × 3mm DFN packages with exposed pads for low thermal resistance. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. Burst Mode is a registered trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. V OUT 3 ...
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... LT3480EMSE LT3480EMSE#TR LT3480IMSE LT3480IMSE#TR Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. *The temperature grade is identifi label on the shipping container. For more information on lead free part marking, go to: For more information on tape and reel specifi cations, go to: ELECTRICAL CHARACTERISTICS range, otherwise specifi ...
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ELECTRICAL CHARACTERISTICS range, otherwise specifi cations are 25° PARAMETER Quiescent Current from V IN Quiescent Current from BD Minimum Bias Voltage (BD Pin) Feedback Voltage FB Pin Bias Current (Note 3) FB Voltage Line Regulation ...
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LT3480 TYPICAL PERFORMANCE CHARACTERISTICS Effi ciency 100 V = 12V 34V 24V NEC PLC-0745-5R6 800kHz OUT 50 0 0.2 0.4 0.6 0.8 1.0 1.2 ...
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TYPICAL PERFORMANCE CHARACTERISTICS Switch Voltage Drop 700 600 500 400 300 200 100 0 0 500 1000 1500 2000 2500 SWITCH CURRENT (mA) 3480 G10 Switching Frequency 1.20 1.15 1.10 1.05 1.00 0.95 0.90 0.85 0.80 –50 – ...
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LT3480 TYPICAL PERFORMANCE CHARACTERISTICS Error Amp Output Current –10 –20 –30 –40 –50 –200 –100 0 100 FB PIN ERROR VOLTAGE (V) 3480 G19 V Voltages C 2.50 2.00 CURRENT LIMIT CLAMP 1.50 1.00 ...
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PIN FUNCTIONS BD (Pin 1): This pin connects to the anode of the boost Schottky diode. BD also supplies current to the internal regulator. BOOST (Pin 2): This pin is used to provide a drive voltage, higher than the input ...
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LT3480 OPERATION The LT3480 is a constant frequency, current mode step- down regulator. An oscillator, with frequency set by RT, enables an RS fl ip-fl op, turning on the internal power switch. An amplifi er and comparator monitor the current ...
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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: ⎛ ⎞ OUT − ⎝ ...
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LT3480 APPLICATIONS INFORMATION + V V OUT – MAX ( ) MIN ( ) where V is the maximum operating input voltage, IN(MAX the output voltage, ...
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APPLICATIONS INFORMATION Table 1. Inductor Vendors VENDOR URL PART SERIES Murata www.murata.com LQH55D TDK www.componenttdk.com SLF7045 SLF10145 Toko www.toko.com D62CB D63CB D75C D75F Sumida www.sumida.com CR54 CDRH74 CDRH6D38 CR75 Of course, such a simple design guide will not always result ...
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LT3480 APPLICATIONS INFORMATION Table 2. Capacitor Vendors VENDOR PHONE Panasonic (714) 373-7366 Kemet (864) 963-6300 Sanyo (408) 749-9714 Murata (408) 436-1300 AVX Taiyo Yuden (864) 963-6300 capacitor if the compensation network is also adjusted to maintain the loop bandwidth. A ...
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APPLICATIONS INFORMATION operation, the noise is typically very quiet to a casual ear. If this is unacceptable, use a high performance tantalum or electrolytic capacitor at the output. A fi nal precaution regarding ceramic capacitors concerns the maximum input voltage ...
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LT3480 APPLICATIONS INFORMATION V SW 5V/DIV I L 0.2A/DIV V OUT 10mV/DIV 5μs/DIV V = 12V; FRONT PAGE APPLICATION 10mA LOAD Figure 4. Burst Mode Operation Low-Ripple Burst Mode and Pulse-Skip Mode The LT3480 is capable of ...
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APPLICATIONS INFORMATION BD BOOST V V LT3480 GND 4.7μF (5a) For V > 2.8V OUT BD BOOST LT3480 GND 4.7μF (5b) For 2.5V < V OUT BD BOOST V V ...
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LT3480 APPLICATIONS INFORMATION RUN 15k RUN/SS GND 0.22μF 2ms/DIV Figure 7. To Soft-Start the LT3480, Add a Resisitor and Capacitor to the RUN/SS Pin Synchronizing the LT3480 oscillator to an external fre- quency can be done by connecting a square ...
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APPLICATIONS INFORMATION OUT C1 D1 GND VIAS TO LOCAL GROUND PLANE VIAS TO RUN/SS VIAS TO V VIAS TO SYNC VIAS TO PG OUT Figure 9. A Good PCB Layout Ensures Proper, Low EMI Operation + LOW ...
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LT3480 APPLICATIONS INFORMATION source, forms an under damped tank circuit, and the voltage at the V pin of the LT3480 can ring to twice the IN nominal input voltage, possibly exceeding the LT3480’s rating and damaging the part. If the ...
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... D2: MBR0540 L: TAIYO YUDEN NP06DZB4R7M 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. 3.3V Step-Down Converter ...
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LT3480 TYPICAL APPLICATIONS V IN 8.6V TO 22V TRANSIENT TO 38V 2.2μ 15V TO 36V TRANSIENT TO 60V* 10μF 330pF D: DIODES INC. DFLS240L L: NEC/TOKIN PLC-0755-100 20 5V, 2MHz Step-Down Converter OFF RUN/SS ...
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TYPICAL APPLICATIONS V IN 3.5V TO 27V 4.7μF 330pF D: DIODES INC. DFLS240L L: TAIYO YUDEN NP06DZB3R3M 1.8V Step-Down Converter RUN/SS BOOST ON OFF LT3480 RT 18.2k PG SYNC 68.1k FB GND f = ...
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LT3480 PACKAGE DESCRIPTION 3.50 0.05 1.65 0.05 2.15 0.05 (2 SIDES) 0.25 0.05 0.50 BSC 2.38 0.05 (2 SIDES) RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS NOTE: 1. DRAWING TO BE MADE A JEDEC PACKAGE OUTLINE M0-229 VARIATION OF (WEED-2). CHECK ...
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PACKAGE DESCRIPTION 2.794 0.102 (.110 .004) 5.23 (.206) MIN 0.305 0.038 (.0120 .0015) TYP RECOMMENDED SOLDER PAD LAYOUT 0.254 (.010) GAUGE PLANE 0.18 (.007) NOTE: 1. DIMENSIONS IN MILLIMETER/(INCH) 2. DRAWING NOT TO SCALE 3. DIMENSION DOES NOT INCLUDE MOLD ...
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... TSSOP 1.2V 2.5mA 25μA, 16-Pin TSSOP 1.2V 100μA, I <1μA, 16-Pin TSSOP Package 1.26V 50μA, I <1μA, 10-Pin 3mm x 3mm 1.26V 1.5mA, I <1μA, 10-Pin 3mm x 3mm 0308 REV B • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2008 3480fb ...