Datasheet LTC3858-2 (Analog Devices) - 6

LTC3858-2
TYPICAL PERFORMANCE CHARACTERISTICS Total Input Supply Current EXTVCC Switchover and INTVCC vs Input Voltage Voltages vs Temperature INTVCC Line Regulation
400 5.6 5.2 FIGURE 12 CIRCUIT 350 VOUT = 3.3V 5.4 ONE CHANNEL ON 300 5.2 INTV 5.2 CC 250 300μA LOAD 5.0 VOLTAGE (V) CC EXTVCC RISING 200 4.8 5.1 VOLTAGE (V) NO LOAD CC 150 4.6 EXTVCC FALLING AND INTV INTV SUPPLY CURRENT (μA) 100 CC 4.4 5.1 EXTV 50 4.2 0 4.0 5.0 5 10 15 20 25 30 35 40 –45 –20 5 30 55 80 105 130 0 5 10 15 20 25 30 35 40 INPUT VOLTAGE (V) INPUT VOLTAGE (V) TEMPERATURE (°C) 38582 G12 38582 G10 38582 G11
Maximum Current Sense Voltage Maximum Current Sense vs ITH Voltage SENSE– Pin Input Bias Current Threshold vs Duty Cycle
80 0 80 PULSE-SKIPPING –50 FORCED CONTINUOUS ILIM = INTVCC 60 Burst Mode OPERATION –100 (FALLING) –150 TAGE (mV) 60 Burst Mode OPERATION I 40 –200 LIM = FLOAT (RISING) –250 20 –300 40 CURRENT (μA)– –350 ILIM = GND ILIM = GND –400 0 ILIM = FLOAT SENSE –450 ILIM = INTVCC 20 –500 –20 CURRENT SENSE THRESHOLD (mV) –550 5% DUTY CYCLE MAXIMUM CURRENT SENSE VOL –600 –40 0 0 5 10 15 20 25 0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 0 10 20 30 40 50 60 70 80 90 100 VSENSE COMMON MODE VOLTAGE (V) ITH PIN VOLTAGE DUTY CYCLE (%) 38582 G14 38582 G13 38582 G15
Foldback Current Limit Quiescent Current vs Temperature Shutdown Current vs Temperature
90 230 10 PLLIN/MODE = 0 80 ILIM = INTVCC VIN = 12V 210 VOUT = 3.3V 9 TAGE (mV) 70 ONE CHANNEL ON 60 190 8 ILIM = FLOAT 50 170 7 40 ILIM = GND 30 150 6 20 QUIESCENT CURRENT (μA) SHUTDOWN CURRENT (μA) 130 5 10 MAXIMUM CURRENT SENSE VOL 0 110 4 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 –45 –20 5 30 55 80 105 130 –45 –20 5 30 55 80 105 130 FEEDBACK VOLTAGE (V) TEMPERATURE (°C) TEMPERATURE (°C) 38582 G17 38582 G16 38582 G18 38582f 6