Datasheet LT3475, LT3475-1 (Analog Devices) - 4

LT3475/LT3475-1
W U TYPICAL PERFOR A CE CHARACTERISTICS LED Current vs VADJ LED Current vs Temperature Switch On Voltage
1.50 1.2 600 TA = 25°C TA = 25°C VADJ = VREF • 2/3 1.25 1.0 500 1.00 0.8 400 0.75 0.6 300 V LED CURRENT (A) 0.50 LED CURRENT (A) 0.4 ADJ = VREF • 7/30 200 SWITCH ON VOLTAGE (mV) 0.25 0.2 100 0 0 0 0 0.25 0.5 0.75 1 1.25 –50 –25 0 25 50 75 100 125 0 0.5 1.0 1.5 2.0 VADJ (V) TEMPERATURE (˚C) SWITCH CURRENT (A) 3475 G01 3475 G02 3475 G03
Switch Current Limit Switch Current Limit vs vs Duty Cycle Temperature Current Limit vs Output Voltage
3.0 3.5 3.0 TA = 25°C TYPICAL 2.5 3.0 2.5 2.5 2.0 2.0 MINIMUM 2.0 1.5 1.5 1.5 1.0 CURRENT LIMIT (A) 1.0 CURRENT LIMIT (A) 1.0 CURRENT LIMIT (A) 0.5 0.5 0.5 TA = 25°C 0 0 0 0 20 40 60 80 100 –50 –25 0 25 50 75 100 125 0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 DUTY CYCLE (%) TEMPERATURE (°C) VOUT (V) 3475 G04 3475 G05 3475 G06
Oscillator Frequency vs Temperature Oscillator Frequency Foldback Oscillator Frequency vs RT
700 700 RT = 24.3kΩ TA = 25°C TA = 25°C RT = 24.3kΩ 650 600 1000 500 600 400 550 300 500 200 OSCILLATOR FREQUENCY (kHz) 450 OSCILLATOR FREQUENCY (kHz) OSCILLATOR FREQUENCY (kHz) 100 400 0 10 –50 –25 0 25 50 75 100 125 0 0.5 1.0 1.5 2.0 2.5 1 10 100 TEMPERATURE (˚C) VOUT (V) RT (kΩ) 3475 G07 3475 G08 3475 G09 3475fb 4