lt3591 Linear Technology Corporation, lt3591 Datasheet
lt3591
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lt3591 Summary of contents
Page 1
... LT, LTC and LTM are registered trademarks of Linear Technology Corporation. True Color PWM is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. R SENSE 10 2.2 F 3591 TA01a LT3591 White LED Driver with 3mm × 2mm DFN Conversion Effi ciency 3.6V IN ...
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... V = 30V R Note 2: The LT3591E is guaranteed to meet performance specifi cations from 0°C to 85°C operating junction temperature range. Specifi cations over the –40°C to 85°C operating junction temperature range are assured by design, characterization and correlation with statistical process controls. ...
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... C 43 125 C 42 – ( 5V/DIV V 5V/DIV 500mA/DIV 3591 G07 500ms/DIV LT3591 T = 25°C, unless otherwise specifi ed. A Shutdown Current (V CTRL – 125 1200 V (V) IN 3591 G02 Input Current in Output ...
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... LT3591 TYPICAL PERFORMANCE CHARACTERISTICS Quiescent Current (V = 3V) CTRL 125 C 4 – (V) IN 3591 G09 Open-Circuit Output Clamp Voltage vs Temperature –50 – 100 TEMPERATURE ( C) 3591 G12 Maximum Duty Cycle vs Temperature ...
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... PCB ground to achieve the rated thermal performance. PWM COMP – DRIVER – RAMP GENERATOR OSCILLATOR – CTRL 8 Figure 1. Block Diagram LT3591 ). The CTRL pin must not be SENSE 4 SW CAP 5 Q1 OVERVOLTAGE PROTECTION 6.25 LED – 7 GND 2 3591 F01 3591f 5 ...
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... LED current. The LT3591 enters into shutdown when CTRL is pulled lower than 50mV. Minimum Output Current The LT3591 can drive a 2-LED string at 2mA LED current without pulse skipping using the same external compo- nents shown in the application circuit on the front page of this data sheet ...
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... APPLICATIONS INFORMATION INDUCTOR SELECTION A 22µH inductor is recommended for most LT3591 ap- plications. Although small size and high effi ciency are major concerns, the inductor should have low core losses at 1MHz and low DCR (copper wire resistance). Some small inductors in this category are listed in Table 1. The effi ...
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... V pin, an inrush current fl ows IN through the inductor and the Schottky diode and charges up the CAP voltage. The Schottky diode inside the LT3591 can sustain a maximum current of 1A. 8 For low DCR inductors, which is usually the case for this application, the peak inrush current can be simplifi ...
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... LED in the string 3591 F05 Figure 6. Li-Ion to Ten White LEDs with Direct PWM Dimming LT3591 CAP LT3591 SENSE GND LED CTRL PWM FREQ 5V Q1 Si2308 0V 100k C2 2.2 F 3591f 9 ...
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... Figure 6. A Si2308 MOSFET can be used since its source is connected to ground. The PWM signal is applied to the CTRL pin of the LT3591 and the gate of the MOSFET. The PWM signal should traverse between 0V to 5V, to ensure proper turn on and off of the driver and the NMOS transistor Q1 ...
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... APPLICATIONS INFORMATION LOW INPUT VOLTAGE APPLICATIONS The LT3591 can be used in low input voltage applications. The input supply voltage to the LT3591 must be 2.5V or higher. However, the inductor can be run off a lower battery voltage. This technique allows the LEDs to be powered off two alkaline cells. Most portable devices have a 3.3V logic supply voltage which can be used to power the LT3591 ...
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... AND DIMMING CONTROL GND C1:TAIYO YUDEN EMK107BJ105MA C2: MURATA GRM31CR71H225KA88 Li-Ion Driver for Four White LEDs at 50mA SHUTDOWN AND DIMMING CONTROL CTRL CAP LT3591 LED GND C1:TAIYO YUDEN EMK107BJ105MA C2: MURATA GRM31CR71H475KA12L L1: MURATA LQH32CN100K53 12 D1 *OPTIONAL R SENSE 10 C2 2.2 F ...
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... C1: TAIYO YUDEN EMK107BJ105MA C2: MURATA GRM31CR71H475KA12L C3: MURATA GRM21BR71H105KA12L L1: TAIYO YUDEN NR4018T220M 3591 TA05a 3591 TA06a 70 0 LT3591 Effi ciency 100 LED CURRENT (mA) 3591 TA05b Effi ciency 100 LED CURRENT (mA) 3591 TA06b 3591f 13 ...
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... GND C1: TAIYO YUDEN EMK107BJ105MA C2: MURATA GRM31CR71H225KA88 L1: TAIYO YUDEN NR4018T220M Li-Ion Driver for Eight White LEDs SHUTDOWN AND DIMMING CONTROL CTRL CAP LT3591 LED GND C1: TAIYO YUDEN EMK107BJ105MA C2: MURATA GRM31CR71H225KA88 L1: TAIYO YUDEN NR4018T220M LEDs 80 75 ...
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... DDB Package 8-Lead Plastic DFN (3mm × 2mm) (Reference LTC DWG # 05-08-1702 Rev B) 0.70 0.05 PACKAGE OUTLINE 0.50 BSC R = 0.115 R = 0.05 TYP 2.00 0.10 (2 SIDES) 0.56 0.05 (2 SIDES) 0.25 0.05 0.75 0.05 0 – 0.05 BOTTOM VIEW—EXPOSED PAD LT3591 0.40 0.10 TYP 5 8 PIN 0.20 OR 0.25 45 CHAMFER 4 1 (DDB8) DFN 0905 REV B 0.50 BSC 2.15 0.05 (2 SIDES) 15 3591f ...
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... LT3591 TYPICAL APPLICATION Li-Ion Driver for Nine White LEDs SHUTDOWN AND DIMMING CONTROL CTRL CAP LT3591 LED GND C1: TAIYO YUDEN EMK107BJ105MA C2: MURATA GRM31CR71H225KA88 L1: TAIYO YUDEN NR4018T220M RELATED PARTS PART NUMBER DESCRIPTION LT1618 Constant-Current, Constant Voltage 1.24MHz, High Effi ciency ...