LT3477EUF#TRPBF Linear Technology, LT3477EUF#TRPBF Datasheet
LT3477EUF#TRPBF
Specifications of LT3477EUF#TRPBF
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LT3477EUF#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 constant- 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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... TAPE AND REEL LT3477EFE#PBF LT3477EFE#TRPBF LT3477IFE#PBF LT3477IFE#TRPBF LT3477EUF#PBF LT3477EUF#TRPBF LT3477IUF#PBF LT3477IUF#TRPBF Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. Consult LTC Marketing for information on non-standard lead based fi nish parts. For more information on lead free part marking, go to: For more information on tape and reel specifi ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi cations are at T PARAMETER Maximum V Pin Current REF Soft-Start Pin Current FBP Pin Bias Current FBN Pin Bias Current Feedback Amplifi er Offset Voltage Feedback Amplifi er Voltage Gain Voltage Feedback Amplifi ...
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LT3477 TYPICAL PERFORMANCE CHARACTERISTICS SHDN Pin Turn-On Threshold 1.6 1.4 1.2 1.0 –50 – 100 TEMPERATURE (°C) 3477 G04 Soft-Start Pin Current –50 – 100 125 150 ...
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TYPICAL PERFORMANCE CHARACTERISTICS Current Sense Voltage vs Temperature 104 103 102 101 V = 10V CM 100 42V –50 – TEMPERATURE (°C) PIN FUNCTIONS (QFN/TSSOP) NC (Pins 1, 2, 20/Pins 18, ...
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LT3477 PIN FUNCTIONS (QFN/TSSOP) I (Pin 13/Pin 11): Second Current Sense (+) Pin. The SP2 noninverting input to the second current sense amplifi er. Connect not used. SN2 I (Pin 14/Pin 12): Second Current Sense (–) Pin. ...
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OPERATION The LT3477 uses a fi xed frequency, current mode control scheme to provide excellent line and load regulation. Op- eration can be best understood by referring to the Block Diagram in Figure 1. The start of each oscillator cycle ...
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LT3477 APPLICATIONS INFORMATION 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 their capacitance over wider voltage ...
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APPLICATIONS INFORMATION 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 =1.235V 1+ OUT R2 FBP LT3477 V REF FBN Figure 2. ...
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LT3477 APPLICATIONS INFORMATION some tweaking of the compensation values (R on the V pin) may be required to ensure a clean inductor C ripple current while the constant-current loop is in effect. For these applications, the constant-current loop response can ...
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APPLICATIONS INFORMATION 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 the LED—analog dimming—but changing LED ...
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LT3477 APPLICATIONS INFORMATION 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 LED1 TO LED4: LUMILEDS LXHL-BW02 Figure ...
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APPLICATIONS INFORMATION 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: LUMILEDS LXHL-BW02 V 3.3V PWM ...
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LT3477 APPLICATIONS INFORMATION 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 0 100Hz Figure 9a. 10V ...
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TYPICAL APPLICATIONS 5.5V SEPIC Converter With Short-Circuit Protection L1 R1 4.7μH 0.04Ω 16V 3.3μ SP1 SN1 ADJ1 I ADJ2 SHDN SHDN LT3477 REF R C FBP GND ...
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LT3477 TYPICAL APPLICATIONS 87% Effi cient, 4W LED Driver R4 L2 0.05Ω 10μ 3.3μ SP1 SN1 ADJ1 I ADJ2 SHDN SHDN LT3477 REF R C FBP GND ...
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TYPICAL APPLICATIONS V IN 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 SN1 V ...
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LT3477 PACKAGE DESCRIPTION 4.50 ± 0.05 3.10 ± 0.05 2.45 ± 0.05 (4 SIDES) RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS 4.00 ± 0.10 (4 SIDES) PIN 1 TOP MARK (NOTE 6) NOTE: 1. DRAWING IS PROPOSED TO BE MADE A ...
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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 representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. FE Package 20-Lead Plastic TSSOP (4 ...
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... I = 0.9mA, I < 6μA, TSSOP16E Package 5.5V 2.5mA, I < 1μA, QFN16 Package 40V 5mA, I < 16μA, DFN Package 40V 5mA, I < 1μA, DFN/TSSOP Packages 4.7V, I < 1μA, DFN/SO8 Packages SD LT 0309 REV C • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2005 3477fc ...