lt3517 Linear Technology Corporation, lt3517 Datasheet
lt3517
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lt3517 Summary of contents
Page 1
... The external PWM input provides up to 5000:1 LED dimming. The CTRL pin provides further 10:1 dimming ratio. The LT3517 is available in the tiny footprint 16-Lead QFN (4mm × 4mm) and the16-Pin TSSOP packages. The LT3517 provides a complete solution for both constant-voltage and constant-current applications ...
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... SW, ISP , ISN, TG ........................................................45V TG Pin Below ISP Pin ................................................10V FB, SYNC, SS, CTRL ................................................... ................................................................. REF Operating Junction Temperature Range (Notes 2,4) LT3517E ..............................................–40ºC to 125ºC LT3517I ...............................................–40ºC to 125ºC LT3517H .............................................–40ºC to 150ºC PIN CONFIGURATION TOP VIEW SHDN ...
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... R = 4.03k (2.5MHz 45V, PWM = 0V SW Current Out of Pin 0.1V CTRL PWM = 0V Current Out of Pin 0.5V FB PWM = 0V ISP Tied to ISN 24V ISP CTRL LT3517 MIN TYP MAX UNITS ● 96 100 103 mV 100 0.03 %/ 4.5 mA ...
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... The LT3517I is guaranteed over the full –40°C to 125°C operating junction temperature range. The LT3517H is guaranteed over the full –40ºC to 150ºC operating junction temperature range. Operating lifetime is derated at junction temperatures greater than 125ºC ...
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... 2.01 2.00 1.99 1.98 50 –40 – 100 120 140 160 TEMPERATURE (°C) PMOS Turn-On 5V PWM 0V 40V TG 30V V = 40V 200ns/DIV ISP LT3517 Oscillator Frequency vs Temperature 2 6.04k T 2.3 2.1 1.9 1.7 1.5 –40 – 100 120 140 TEMPERATURE (°C) 3518 G05 Quiescent Current ...
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... LT3517 PIN FUNCTIONS SW: Switch Pin. Minimize trace at this pin to reduce EMI Input Supply Pin. Must be locally bypassed. IN SHDN: Shutdown Pin. Tie to 1.5V or higher to enable device or 0.4V or less to disable device Reference Output Pin. This pin can supply up to REF 100μ Switching Frequency Adjustment Pin. Set switching ...
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... ISP MOSFET DRIVER ERROR AMPLIFIER + + – PWM COMPARATOR SS RAMP GENERATOR 2.5MHz TO 250kHz OSCILLATOR A6 Q2 FREQ ADJUST V IN Figure 1. Buck Mode LED Driver LT3517 C FILT SW PWM MAIN SWITCH DRIVER Q1 POWER R Q SWITCH GND – 100μA V REF + A7 – ...
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... APPLICATIONS INFORMATION Dimming Control There are two methods to control the current source for dimming using the LT3517. The fi rst method uses the PWM pin to modulate the current source between zero and full current to achieve a precisely programmed aver- age current. To make this method of current control more accurate, the switch demand current is stored on the V node during the quiescent phase ...
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... OUT (3) if not REF Inductor Selection The inductor used with the LT3517 should have a satura- 49.9k tion current rating greater. For buck mode LED CTRL drivers, the inductor value should be chosen to give a ripple current “ΔI” of ~30% to 40% of the LED current. ...
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... Taiyo Yuden (8) AVX Murata TDK Loop Compensation The LT3517 uses an internal transconductance error amplifi er whose V The external inductor, output capacitor, and the compen- sation resistor and capacitor determine the loop stability. The inductor and output capacitor are chosen based on PHONE ...
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... International Rectifi er 10MQ060N 60 Board Layout The high speed operation of the LT3517 demands careful attention to board layout and component placement. The Exposed Pad of the package is the only GND terminal of the IC and is also important for thermal management of the IC crucial to achieve a good electrical and thermal or CTRL ...
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... GND. T Thermal Considerations T The LT3517 is rated to a maximum input voltage of 30V for continuous operation, and 40V for nonrepetitive one second transients. Careful attention must be paid to the internal power dissipation of the LT3517 at higher input R ( kΩ ) ...
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... I 16.9k LED 0.1μF 1MHz 3517 TA02a D1 V OUT 12V 350mA R1 549k C2 10μF R2 49. 6.04k 2MHz 3517 TA03a LT3517 2000:1 PWM Dimming at 120Hz 1μs/DIV 3517 TA02b = 24V IN = 1MHz = 1A Effi ciency 100 150 200 250 300 350 I (mA) ...
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... I L 1A/DIV 500ns/DIV V = 12V 2MHz OSC I = 300mA LED 14 Buck-Boost Mode LED Driver L1 D1 6.8μH SHDN PWM PWM LT3517 ISP TGEN V REF CTRL ISN TG SYNC GND 6.04k 2MHz C4 C3 0.1μF 0.1μF 3517 TA04b C5 R1 0.22μF 3 ...
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... C3 0.1μF 3517 TA05b V 10V/DIV ISP V 10V/DIV IN I 200mA/DIV LED I 1A/DIV L 3517 TA05d LT3517 C5 0.22μF C2 4.7μF D1: DIODES DFLS160 L1: TOKO B992AS-6R8N C1: KEMET C0806C225K4RAC C2: KEMET C1206C475K3RAC C3: MURATA GRM21BR71H104KA01B C4: MURATA GRM219R71H333KAQ01B C5: MURATA GRM21BR71H224KA01B M1: ZETEX ZXMP6A13FTA 3517 TA05a LEDs: LUXEON I (WHITE) Effi ciency 12V ...
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... I L 500mA/DIV 1μs/DIV V = 12V 1MHz OSC I = 100mA LED 16 Boost 100mA LED Driver with LED Open Protection L1 D1 22μH SHDN ISP PWM R TGEN 1Ω LT3517 ISN V REF TG CTRL M1 SYNC GND 100mA T 16.9k 1MHz 30.1k 0.1μF 3517 TA06b ...
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... C4: MURATA GCM033R71A103KA03 D1: ZETEX ZLLS1000TA L1, L2: TOKO B992AS-4R3N C5 R 10μF SENSE D1 0.22Ω 10μF 221k 4.3μ 49. 6.04k 0.1μF 2MHz 3517 TA07a LT3517 Effi ciency V OUT 90 5.5V 350mA 100 150 200 I (mA) LOAD 250 300 350 3517 TA07b ...
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... LT3517 PACKAGE DESCRIPTION 4.35 ± 0.05 2.15 ± 0.05 (4 SIDES) 2.90 ± 0.05 RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS 4.00 ± 0.10 (4 SIDES) PIN 1 TOP MARK (NOTE 6) NOTE: 1. DRAWING CONFORMS TO JEDEC PACKAGE OUTLINE MO-220 VARIATION (WGGC) 2. DRAWING NOT TO SCALE 3. ALL DIMENSIONS ARE IN MILLIMETERS 4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE MOLD FLASH ...
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... BSC 4. RECOMMENDED MINIMUM PCB METAL SIZE FOR EXPOSED PAD ATTACHMENT MILLIMETERS (INCHES) *DIMENSIONS DO NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED 0.150mm (.006") PER SIDE LT3517 4.90 – 5.10* (.193 – .201) 2.74 (.108) 16 1514 6.40 2.74 (.252) ( ...
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... LT3517 RELATED PARTS PART NUMBER DESCRIPTION LT1618 Constant Current, 1.4MHz, 1.5A Boost Converter LT3003 3-Channel LED Ballaster with PWM Dimming LT3474 36V 2MHz, Step-Down LED Driver LED LT3475 Dual 1. 36V 2MHz Step-Down LED Driver LED LT3476 Quad Output 1.5A, 36V, 2MHz High Current LED Driver ...