Datasheet LTC3425 (Analog Devices) - 5

LTC3425
W U TYPICAL PERFOR A CE CHARACTERISTICS Converter Efficiency Converter Efficiency Converter Efficiency for 2-, 3- and for VOUT = 3.3V for V 4-Phase Operation OUT = 5V
100 100 98 T V V A = 25°C 90 IN = 2.4V IN = 3.3V 90 96 VIN = 2.4V VOUT = 3.3V 80 80 VIN = 2.4V 94 1MHz/PHASE VIN = 1.2V 70 70 V 92 IN = 2.4V VIN = 3.3V VIN = 2.4V 60 60 VIN = 1.2V 90 50 50 4 PHASE 88 40 40 EFFICIENCY (%) EFFICIENCY (%) EFFICIENCY (%) 86 30 30 2 PHASE 3 PHASE 20 84 20 10 Burst Mode OPERATION 10 Burst Mode OPERATION 82 TA = 25°C 1MHz/PHASE T 1MHz/PHASE 0 A = 25°C 0 80 0.1 1 10 100 1000 10000 0.1 1 10 100 1000 10000 100 1000 10000 OUTPUT CURRENT (mA) OUTPUT CURRENT (mA) LOAD (mA) 3425 G11 3425 G13 3425 G12
Efficiency Comparison of Efficiency Comparison of Discontinuous Mode and Forced Discontinuous Mode and Forced Continuous Mode at Light Loads Continuous Mode at Light Loads Converter No Load Input Current for VIN = 2.4V, VOUT = 3.3V for VIN = 3.3V, VOUT = 5V vs VIN (Burst Mode Operation)
100 100 140 TA = 25°C TA = 25°C TA = 25°C 90 1MHz/PHASE 90 1MHz/PHASE 120 80 DISCONTINUOUS 80 µA) MODE DISCONTINUOUS 70 70 MODE 100 60 FORCED 60 VOUT = 5V CONTINUOUS FORCED 80 50 MODE 50 CONTINUOUS MODE 60 40 40 EFFICIENCY (%) EFFICIENCY (%) VOUT = 3.3V 30 30 40 20 20 CONVERTER INPUT CURRENT ( 20 10 10 0 0 0 1 10 100 1000 1 10 100 1000 1.5 2.0 2.5 3.0 3.5 4.0 4.5 CONVERTER OUTPUT CURRENT (mA) LOAD (mA) VIN (V) 3425 G14 3425 G15 3425 G16
Oscillator Frequency Peak Current Limit Effective RDS(ON)
10 1.8 0.065 TA = 25°C TA = 25°C TA = 25°C 1.6 0.060 1.4 PMOS 0.055 1.2 0.050 NMOS FREQUENCY (MHz) 1.0 (ALL FOUR PHASES IN PARALLEL) 0.045 0.8 PEAK CURRENT IN EACH PHASE (A) DS(ON)R 1 0.6 0.040 1 10 100 60 80 100 120 140 160 180 200 2.5 3 3.5 4 4.5 5 RT (kΩ) ILIM RESISTOR (kΩ) VOUT (V) 3425 G17 3425 G18 3425 G19 3425f 5