Datasheet LT3744 (Analog Devices) - 7

LT3744
Typical perForMance characTerisTics VBOOST - VSW UVLO INTVCC UVLO (Falling Threshold) (Falling Threshold) Oscillator Frequency
3.0 3.5 1.4 200kHz 2.95 3.4 1MHz 2.9 3.3 1.2 2.85 3.2 1.0 2.8 (V) 3.1 (V) SW 0.8 V CC 2.75 - V 3.0 INT 2.7 2.9 0.6 V BOOST 2.65 2.8 FREQUENCY (MHz) 0.4 2.6 V 2.7 IN = 3.3V VIN = 3.3V 0.2 2.55 VIN = 12V 2.6 VIN = 12V VIN = 36V VIN = 36V 2.5 2.5 0.0 –50 –25 0 25 50 75 100 125 –50 –25 0 25 50 75 100 125 –50 –25 0 25 50 75 100 125 TEMPERATURE (°C) TEMPERATURE (°C) TEMPERATURE (°C) 3744 G10 3744 G11 3744 G12
Frequency Foldback RT Pin Current Limit INTVCC Load Regulation
1.2 70 6 1.0 65 5 0.8 60 4 (V) 0.6 (µA) 55 V CC 3 I RT INT 0.4 50 2 0.2 T = 125°C 45 VIN = 3.3V 1 T = 130°C T = 25°C V T = 25°C NORMALIZED OSCILLATOR FREQUENCY IN = 12V T = –50°C VIN = 36V T = –50°C 0 40 0 0 100 200 300 400 500 600 –50 –25 0 25 50 75 100 125 0 10 20 30 40 50 60 70 FB PIN VOLTAGE (mV) TEMPERATURE (°C) INTVCC (mA) 3744 G13 3744 G14 3744 G15
INTVCC Current Limit Lower FAULT Threshold (Falling) Upper FAULT Threshold (Rising)
70 300 1.2 VLED_ISP - VLED_ISN < 6mV 290 1.18 60 280 1.16 50 270 1.14 40 260 1.12 TAGE (V) TAGE (mV) 250 1.1 30 PIN CURRENT (mA) VOL 240 PIN VOL 1.08 V CC V FB 20 230 V FB 1.06 INT V 220 V 1.04 V 10 IN = 3.3V IN = 3.3V IN = 3.3V VIN = 12V 210 VIN = 12V 1.02 VIN = 12V VIN = 36V VIN = 36V VIN = 36V 0 200 1.0 –50 –25 0 25 50 75 100 125 –50 –25 0 25 50 75 100 125 –50 –25 0 25 50 75 100 125 TEMPERATURE (°C) TEMPERATURE (°C) TEMPERATURE (°C) 3744 G16 3744 G17 3744 G18 3744fa For more information www.linear.com/LT3744 7 Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Typical Application Related Parts