Datasheet LT8645S-2 (Analog Devices) - 5

LT8645S-2
TYPICAL PERFORMANCE CHARACTERISTICS 12VIN to 5VOUT Efficiency 12VIN to 3.3VOUT Efficiency vs Frequency vs Frequency Efficiency at 5VOUT
100 4.0 100 4.0 100 4.0 EFFICIENCY 95 3.5 95 3.5 95 3.6 90 3.2 90 EFFICIENCY 3.0 90 3.0 POWER LOSS (W) EFFICIENCY POWER LOSS (W) 85 2.8 POWER LOSS (W) 85 2.5 85 2.5 fSW = 500kHz 80 L = XEL6060, 2.7µH 2.4 80 2.0 80 2.0 75 2.0 75 1.5 70 1.6 EFFICIENCY (%) 75 1.5 EFFICIENCY (%) EFFICIENCY (%) POWER LOSS POWER LOSS 65 1.2 70 L = XEL6060 1.0 70 L = XEL6060 1.0 VIN = 12V 500kHz, L = 2.7µH 500kHz, L = 2.7µH 60 V 0.8 IN = 24V 65 1MHz, L = 2.2µH 0.5 65 1MHz, L = 1.5µH 0.5 V 55 IN = 36V 0.4 2MHz, L = 1µH 2MHz, L = 0.82µH POWER LOSS VIN = 48V 60 0 60 0 50 0 1 2 3 4 5 6 7 8 1 2 3 4 5 6 7 8 0 1 2 3 4 5 6 7 8 LOAD CURRENT (A) LOAD CURRENT (A) LOAD CURRENT (A) 8645S-2 G01 8645S-2 G02 8645S-2 G03
Efficiency at 3.3VOUT Low Load Efficiency at 5VOUT Low Load Efficiency at 3.3VOUT
100 4.0 100 100 EFFICIENCY 95 3.6 90 90 90 3.2 80 80 85 2.8 POWER LOSS (W) 80 2.4 70 70 fSW = 500kHz 75 L = XEL6060, 2.7µH 2.0 60 60 70 1.6 EFFICIENCY (%) 50 V EFFICIENCY (%) IN = 12V 50 VIN = 12V EFFICIENCY (%) 65 1.2 VIN = 24V VIN = 24V V 40 V 40 V IN = 12V IN = 36V IN = 36V 60 V 0.8 V V IN = 24V IN = 48V IN = 48V 55 V 30 30 IN = 36V 0.4 fSW = 500kHz fSW = 500kHz POWER LOSS VIN = 48V L = WE–LHMI7050, 4.7µH L = WE–LHMI7050, 4.7µH 50 0 20 20 0 1 2 3 4 5 6 7 8 0.01 0.1 1 10 100 1000 0.01 0.1 1 10 100 1000 LOAD CURRENT (A) LOAD CURRENT (mA) LOAD CURRENT (mA) 8645S-2 G04 8645S-2 G05 8645S-2 G06
Burst Mode Operation Efficiency Efficiency vs Frequency vs Inductor Value Reference Voltage oltage
96 100 979 94 977 95 V V IN = 12V IN = 12V 92 975 90 973 90 85 TAGE (mV) 971 88 VIN = 24V 969 V 80 IN = 24V 86 EFFICIENCY (%) EFFICIENCY (%) 967 75 84 REFERENCE VOL 965 VOUT = 3.3V VOUT = 5V 82 I 70 LOAD = 2A ILOAD = 10mA 963 L = XEL6060, 4.7µH L = WE–LHMI7050 80 65 961 0.4 0.7 1 1.3 1.6 1.9 2.2 1 2 3 4 5 6 7 8 9 10 –50 –25 0 25 50 75 100 125 150 SWITCHING FREQUENCY (MHz) INDUCTOR VALUE (µH) TEMPERATURE (°C) 8645S-2 G07 8645S-2 G08 8645S2 G09 Rev 0 For more information www.analog.com 5 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Order Information Pin Configuration Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Package Description Typical Applications Related Parts