lt3477iuf-trpbf Linear Technology Corporation, lt3477iuf-trpbf Datasheet
lt3477iuf-trpbf
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lt3477iuf-trpbf Summary of contents
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... Available in thermally enhanced 20-pin (4mm × 4mm) QFN and 20-pin TSSOP packages, the LT3477 provides a complete solution for both constant-voltage and con- stant-current applications. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. 3.3µF 200k ...
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... JMAX JA EXPOSED PAD (PIN 21) IS PGND (MUST BE SOLDERED TO PCB) ORDER PART NUMBER UF PART MARKING LT3477EUF LT3477IUF Order Options Tape and Reel: Add #TR Lead Free: Add #PBF Lead Free Tape and Reel: Add #TRPBF Lead Free Part Marking: http://www.linear.com/leadfree/ Consult LTC Marketing for parts specified with wider operating temperature ranges. ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T PARAMETER Soft-Start Pin Current FBP Pin Bias Current FBN Pin Bias Current Feedback Amplifier Offset Voltage Feedback Amplifier Voltage Gain Voltage Feedback Amplifier Transconductance Feedback Amplifier Sink Current Feedback Amplifier Source ...
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LT3477 W U TYPICAL PERFOR A CE CHARACTERISTICS SHDN Pin Turn-On Threshold 1.6 1.4 1.2 1.0 – 100 125 –25 0 TEMPERATURE (°C) 3477 G04 Soft-Start Pin Current –50 – ...
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W U TYPICAL PERFOR A CE CHARACTERISTICS Current Sense Voltage vs Temperature 104 103 102 101 V = 10V CM 100 42V –50 – TEMPERATURE (° ...
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LT3477 CTIO S (QFN/TSSOP) I (Pin 13/ Pin 11): Second Current Sense (+) Pin. The SP2 noninverting input to the second current sense amplifier. Connect not used. SN2 I (Pin 14/ Pin ...
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U OPERATIO The LT3477 uses a fixed frequency, current mode control scheme to provide excellent line and load regulation. Operation can be best understood by referring to the Block Diagram in Figure 1. The start of each oscillator cycle sets ...
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LT3477 U U APPLICATIO S I FOR ATIO Capacitor Selection Low ESR (equivalent series resistance) ceramic capaci- tors should be used at the output to minimize the output ripple voltage. Use only X5R or X7R dielectrics, as these materials retain ...
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U U APPLICATIO S I FOR ATIO Setting Positive Output Voltages To set a positive output voltage, select the values of R1 and R2 (see Figure 2) according to the following equation: ⎛ ⎞ ⎜ ⎟ ...
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LT3477 U U APPLICATIO S I FOR ATIO is a triangular waveform (not a DC waveform like the output current) some tweaking of the compensation val- ues (R and C on the V pin) may be required to ensure C ...
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U U APPLICATIO S I FOR ATIO PWM Dimming For LED applications where a wide dimming range is required, two competing methods are available: analog dimming and PWM dimming. The easiest method is to simply vary the DC current through ...
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LT3477 U U APPLICATIO S I FOR ATIO V PWM 5V 0 100Hz 100k C1: TAIYO YUDEN EMK316BJ335ML C2: TAIYO YUDEN UDK325BJ106MM L1: TOKO D53LC (PN# A915AY-2ROM) D1: ZETEX ZLLS1000 D2: DIODES INC 1N4148 NMOS1: ZETEX 2N7002 NMOS2: FAIRCHILD FDG327N ...
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U U APPLICATIO S I FOR ATIO C1: NIPPON NTS40X5R1H225M C2: TAIYO YUDEN GMK316BJ105ML C3: TAIYO YUDEN LMK316BJ335KL L1: TOKO D53LC (PN# A915AY-100M) D1: ZETEX ZLLS400 D2: DIODES INC 1N4148 NMOS1, NM0S2: ZETEX 2N7002 PMOS: SILICONIX Si2303BDS LED1 TO LED6: ...
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LT3477 U U APPLICATIO S I FOR ATIO C1: TAIYO YUDEN LMK316BJ335ML C2: TAIYO YUDEN UDK325BJ106MM L1: TOKO D53LC (PN# A915AY-4R7M) D1: ZETEX ZLLS1000 D2: DIODES INC 1N4148 NMOS1, NMOS2: ZETEX 2N7002 PMOS: SILICONIX Si2303BDS LED1, LED2: LUMILEDS LXHL-BW02 5V ...
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U TYPICAL APPLICATIO S 5.5V SEPIC Converter with Short-Circuit Protection L1 R1 4.7µH 0.04Ω 16V 3.3µ SP1 SN1 ADJ1 I ADJ2 LT3477 SHDN SHDN ...
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LT3477 U TYPICAL APPLICATIO S 87% Efficient, 4W LED Driver R4 L2 0.05Ω 10µ 3.3µ SP1 SN1 V FBN IN I ADJ1 I ADJ2 LT3477 SHDN SHDN SN2 V ...
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U TYPICAL APPLICATIO 2.7V TO 10V LED BRIGHTNESS CONTROL 0mV TO 650mV SHDN Buck-Boost Mode LED Driver LED2 LED1 L1 4.7µH C1 3.3µ SW1 SP1 ...
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LT3477 PACKAGE DESCRIPTIO 4.50 ± 0.05 3.10 ± 0.05 2.45 ± 0.05 (4 SIDES) RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS 4.00 ± 0.10 PIN 1 TOP MARK (NOTE 6) NOTE: 1. DRAWING IS PROPOSED TO BE MADE A JEDEC PACKAGE ...
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... DIMENSIONS ARE IN 3. DRAWING NOT TO SCALE 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 Package 20-Lead Plastic TSSOP (4 ...
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... I = 2.5mA, I < 1µA, QFN16 Package OUT(MAX 40V 5mA, I < 16µA, DFN Package OUT(MAX 40V 5mA, I < 1µA, DFN/TSSOP Packages OUT(MAX 4.7V, I < 1µA, DFN/SO8 Packages SD LT 0207 REV B • PRINTED IN THE USA © LINEAR TECHNOLOGY CORPORATION 2005 3477fb ...