Datasheet LT3580 (Analog Devices) - 4

LT3580
TYPICAL PERFORMANCE CHARACTERISTICS TA = 25°C unless otherwise specified Switch Current Limit at Minimum Switch Current Limit at 1MHz Switch Saturation Voltage Duty Cycle
400 2.5 2.5 350 300 2.0 2.0 TAGE (mV) 250 1.5 1.5 200 TION VOL 1.0 150 1.0 TURA SWITCH CURRENT (A) 100 SWITCH CURRENT LIMIT (A) SA 0.5 0.5 50 0 0 0 10 20 30 40 50 60 70 80 90 0 0.5 1 1.5 2 0 200 400 600 800 1000 1200 DUTY CYCLE (%) SWITCH CURRENT (A) SS VOLTAGE (mV) 3580 G01 3580 G02 3580 G03
Switch Current Limit at Minimum Switching Waveforms for Duty Cycle Positive Feedback Voltage Figure 14 Circuit
3.0 1.24 VOUT 50mV/DIV 2.5 1.23 AC COUPLED 2.0 1.22 VSW 1.5 10V/DIV 1.21 1.0 FB VOLTAGE (V) SWITCH CURRENT LIMIT (A) 1.20 0.5 IL 0.5A/DIV 0 1.19 –50 0 50 100 –50 –25 0 25 50 75 100 125 200ns/DIV 3580 G06 TEMPERATURE (°C) TEMPERATURE (°C) 3580 G04 3580 G05
Oscillator Frequency During Oscillator Frequency Soft-Start Internal UVLO
) 2.7 1 2.40 R NOM T = 35.7k 2.38 2.5 TA = –35°C T 2.36 2.3 A = 100°C TA = 25°C 2.34 2.1 2.32 1.9 1/2 2.30 VOLTAGE (V) 2.28 1.7 IN FREQUENCY (MHz) 1/3 V 2.26 1.5 1/4 2.24 INVERTING BOOSTING 1.3 RT = 75k CONFIGURATIONS CONFIGURATIONS 2.22 1.1 0 NORMALIZED OSCILLATOR FREQUENCY (F/F 2.20 –50 0 50 100 0 0.2 0.4 0.6 0.8 1.0 1.2 –50 0 50 100 TEMPERATURE (°C) FB VOLTAGE (V) TEMPERATURE (°C) 3580 G07 3580 G08 3580 G09 3580fg 4