Datasheet LT3474, LT3474-1 (Analog Devices) - 4

LT3474/LT3474-1
TYPICAL PERFORMANCE CHARACTERISTICS LED Current vs VADJ LED Current vs Temperature Switch Voltage Drop
1000 1200 700 TA = 25°C T V A = 25°C ADJ = VREF 1000 600 800 500 800 600 400 600 TAGE DROP (mV) 300 400 400 LED CURRENT (mA) LED CURRENT (mA) 200 V 200 ADJ = VREF/5 200 SWITCH VOL 100 0 0 0 0 0.25 0.5 0.75 1 1.25 –50 –25 0 25 50 75 100 125 0 500 1000 1500 VADJ (V) TEMPERATURE (°C) SWITCH CURRENT (mA) 3474 GO3 3474 G04 3474 G05
Switch Current Limit vs Current Limit vs Duty Cycle Temperature Current Limit vs Output Voltage
2.5 2.5 2.5 TA = 25°C 2 2 2 TYPICAL MINIMUM (85°C) 1.5 1.5 1.5 MINIMUM (125°C) 1 1 1 CURRENT LIMIT (A) CURRENT LIMIT (A) CURRENT LIMIT (A) 0.5 0.5 0.5 0 0 0 0 20 40 60 80 100 –50 –25 0 25 50 75 100 125 0 2 4 6 8 10 12 DUTY CYCLE (%) TEMPERATURE (°C) VOUT (V) 3474 G06 3474 G07 3474 G08
Oscillator Frequency vs Oscillator Frequency vs RT Temperature Oscillator Frequency Foldback
600 600 TA = 25°C RT = 80.6k TA = 25°C RT = 80.6k 500 550 1000 400 500 300 200 450 OSCILLATOR FREQUENCY (kHz) OSCILLATOR FREQUENCY (kHz) OSCILLATOR FREQUENCY (kHz) 100 100 400 0 10 100 –50 –25 0 25 50 75 100 125 0 0.5 1 1.5 2 2.5 RT (kΩ) TEMPERATURE (°C) VOUT (V) 3474 G09 3474 G10 3474 G11 3474fd 4