LT3519 LINER [Linear Technology], LT3519 Datasheet
LT3519
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LT3519 Summary of contents
Page 1
... Constant-Current and Constant-Voltage Regulation n Boost, SEPIC, Buck-Boost Mode or Buck Mode Topology n Open LED Protection and Open LED Status Pin n Programmable Undervoltage Lockout with Hysteresis n Fixed Frequency: 400kHz (LT3519) n Internal Compensation n CTRL Pin Provides Analog Dimming n Low Shutdown Current: <1μA n 16-Lead MSOP Package ...
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... SHDN/UVLO = 12V, CTRL = 2V, PWM = 5V, = 25° CONDITIONS Continuous Operation (Note 3) SHDN/UVLO = 0V (Shutdown) PWM = 0V (Idle) PWM > 1.5V 1.5V (Active, Not Switching) ISP = 24V, CTRL = 2V ISP = 0V, CTRL = 2V ISP = 24V, CTRL = 100mV 2.5V < ISP < 45V 400kHz (LT3519) 400kHz (LT3519 500mA SW TOP VIEW 1 GND 16 GND REF PWM ...
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... Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2. The LT3519E is guaranteed to meet specifi ed performance from 0°C to 125°C. Specifi cations over the –40°C to 125°C operating temperature range are assured by design, characterization and correlation with statistical process controls ...
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... LT3519 TYPICAL PERFORMANCE CHARACTERISTICS V -V Threshold vs V ISP ISN CTRL 300 V = 12V 24V ISP 250 200 150 100 50 0 –50 0.5 1.0 1 (V) CTRL 3519 G01 V V Threshold vs ISP- ISN Temperature 260 V = 12V IN 258 V = 24V ISP CTRL 256 254 252 250 ...
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... TEMPERATURE (°C) Schottky Leakage Current vs Temperature 24V –50 – TEMPERATURE (°C) LT3519 (T = 25°C unless otherwise noted) A SHDN/UVLO Threshold vs Temperature 1. 12V IN 1.28 SHDN/UVLO RISING 1.26 1.24 SHDN/UVLO FALLING 1.22 1.20 –50 – 100 125 TEMPERATURE (°C) 3519 G11 ...
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... LT3519 PIN FUNCTIONS GND (Pins 16): Power Ground and Signal Ground. Tie to GND plane for best thermal performance. OPENLED (Pin 2): Open LED Status Pin. The OPENLED pin asserts if the FB input is greater than the FB regulation threshold minus 60mV (typical). The pin must have an external pull-up resistor to function ...
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... OUT PWM 3 PWM + – ERROR C PWM AMPLIFIER COMPARATOR BANDGAP AND BIAS RAMP GENERATOR V OSCILLATOR IN Q2 LT3519 CATHODE ANODE MAIN SWITCH DRIVER Q1 G1 MAIN SWITCH GND – OPENLED + FB Q4 – ...
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... APPLICATIONS INFORMATION Dimming Control There are two methods to control the current source for dimming using the LT3519. The fi rst method, PWM Dim- ming, uses the PWM pin to modulate the current source between zero and full current to achieve a precisely pro- grammed average current. To make this method of cur- ...
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... Typical Performance CTRL if not used. REF R1 +1 • 1.22V R2 during normal operation will not exceed • SENSE(EXT OUT LED – ARRAY 100k Q1 LT3519 FB R2 3519 F02 -V ISP ISN 3519f 9 ...
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... LT3519 Figure 3. SHDN/UVLO Threshold Programming Inductor Selection The inductor used with the LT3519 should have a saturation current rating greater. For buck mode LED driv- ers, the inductor value should be chosen to give a ripple current 150mA or more. In the buck mode, the inductor ...
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... FB pin to be within 60mV of the 1.22V regulation voltage is for an open LED event to have occurred. Inrush Current The LT3519 have a built-in Schottky diode for a boost converter. When supply voltage is applied to V voltage difference between V and V IN current fl ...
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... Boost Automotive LED Driver L1 68μH C1 1μF SW ANODE CATHODE V ISP IN 1M 100k SHDN/UVLO ISN 1M 243k LT3519 V REF FB CTRL 137k OPENLED GND PWM C1: TDK C3216X7R1H105K PWM C2: MURATA GRM32ER71H475KA88 L1: COILTRONICS DR74-680-R M1: VISHAY SILICONIX Si2328DS R : STACKPOLE ELECTRONICS RHC 2512 2.49 SENSE NOTE 8.2V RISING TURN ON ...
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... L1: COILTRONICS DR73-470-R Q1: DIODES FMMT 555 PNP NOTE 8.2V RISING TURN 6.2V FALLING UVLO IN V > 7V FULL LED CURRENT AND FOLDBACK BELOW IN V – V 18.5V OVERVOLTAGE PROTECTION OUT IN 3519 TA03b LT3519 R SENSE V 1.67Ω OUT C2 1μF 357k C3 4.7μF 10k Q1 24.3k 3519 TA03a Effi ciency ...
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... OUT 10V/DIV OPENLED 10V/DIV V = 15V 25μs/DIV IN 14 Buck Mode 500mA LED Driver 1M CATHODE V IN SHDN SHDN/UVLO ISP 1M CTRL LT3519 100k 191k V ISN REF OPENLED SW ANODE GND PWM PWM 3519 TA04b R SENSE 0.5Ω 1.5k 130k 10μF 9V LED 500mA ...
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... DETAIL “A” MAX SEATING PLANE 0.17 – 0.27 (.007 – .011) 0.50 TYP (.0197) BSC LT3519 (NOTE 3) 0.280 0.076 (.011 .003) 9 REF 3.00 0.102 (.118 .004) (NOTE 4) 0.86 (.034) REF 0.1016 0.0508 (.004 .002) MSOP (MS16) 1107 REV Ø ...
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... V OUT SW ANODE CATHODE C2 V ISP IN 4.7μF R SENSE 1.67Ω SHDN/UVLO ISN 1M LT3519 V REF FB 16V LED CTRL 150mA 69.8k OPENLED GND PWM M1 5V PWM 3519 TA05a 3519 TA05b COMMENTS White LEDs < 1μA, MS Package White LEDs, V Packages Drives 100mA White LEDs ...