Datasheet LTC3857 (Analog Devices) - 6

LTC3857
TYPICAL PERFORMANCE CHARACTERISTICS Total Input Supply Current EXTVCC Switchover and INTVCC vs Input Voltage Voltages vs Temperature INTVCC Line Regulation
500 6.0 5.2 V 450 OUT1 = 3.3V RUN2 = 0V 5.8 400 FIGURE 13 CIRCUIT 5.6 5.1 350 5.4 300 INTV VOLTAGE (V) 5.2 CC TAGE (v) CC 250 500μA 5.0 5.0 EXTV VOL CC RISING 200 4.8 CC 300μA 150 AND INTV 4.6 EXTVCC FALLING INTV SUPPLY CURRENT (μA) CC 4.9 100 4.4 NO LOAD EXTV 50 4.2 0 4.0 4.8 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) TEMPERATURE (°C) INPUT VOLTAGE (V) 3857 G10 3857 G11 3857 G12
Maximum Current Sense Voltage Maximum Current Sense vs ITH Voltage SENSE– Pin Input Bias Current Threshold vs Duty Cycle
80 0 80 5% DUTY CYCLE –50 ILIM = INTVCC 60 –100 PULSE-SKIPPING MODE –150 TAGE (mV) 60 I 40 –200 LIM = FLOAT Burst Mode OPERATION –250 20 –300 40 CURRENT (μA) I – –350 LIM = GND ILIM = GND 0 –400 ILIM = FLOAT SENSE –450 20 –20 ILIM = INTVCC –500 CURRENT SENSE THESHOLD (mV) FORCED CONTINUOUS MODE –550 MAXIMUM CURRENT SENSE VOL –40 –600 0 0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 0 5 10 15 20 25 0 10 20 30 40 50 60 70 80 90 100 V V ITH (V) SENSE COMMON MODE VOLTAGE (V) DUTY CYCLE (%) 3857 G13 3857 G14 3857 G15
Foldback Current Limit Quiescent Current vs Temperature INTVCC vs Load Current
90 80 5.20 VIN = 12V 80 ILIM = INTVCC 75 5.15 TAGE (mV) 70 70 60 I 65 LIM = FLOAT 5.10 50 60 EXTVCC = 0V 40 VOLTAGE (V) ILIM = GND 55 CC 5.05 30 INV EXTV 20 QUIESCENT CURRENT (μA) 50 CC = 8.5V 5.00 45 10 MAXIMUM CURRENT SENSE VOL 0 40 4.95 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 0 20 40 60 80 100 120 140 160 180 200 FEEDBACK VOLTAGE (V) TEMPERATURE (°C) LOAD CURRENT (mA) 3857 G16 3857 G17 3857 G18 3857fd 6 Document Outline FEATURES DESCRIPTION APPLICATIONS TYPICAL APPLICATION ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION ORDER INFORMATION ELECTRICAL CHARACTERISTICS TYPICAL PERFORMANCE CHARACTERISTICS PIN FUNCTIONS FUNCTIONAL DIAGRAM OPERATION APPLICATIONS INFORMATION TYPICAL APPLICATIONS PACKAGE DESCRIPTION REVISION HISTORY TYPICAL APPLICATION RELATED PARTS