Datasheet LTC3777 (Analog Devices) - 6

LTC3777
TYPICAL PERFORMANCE CHARACTERISTICS Efficiency and Power Loss vs Load Current and Input Voltage Efficiency and Power Loss Continuous Mode vs Input Voltage
100 10 100 10 V EFFICIENCY OUT = 12V FIGURE 18 CIRCUIT 96 9 IOUT = 5A VOUT = 48V 92 f 8 97 8 SW = 250kHz 88 7 POWER LOSS (W) POWER LOSS (W) 84 6 94 6 V EFFICIENCY IN = 72V 80 V 5 IN = 48V 76 VIN = 24V 4 91 4 EFFICIENCY (%) EFFICIENCY (%) 72 3 POWER LOSS 68 2 88 2 64 POWER LOSS 1 60 0 85 0 0.1 1 10 5 10 15 20 25 30 35 40 45 50 55 LOAD CURRENT (A) VIN VOLTAGE (V) 3777 G02 CIRCUIT OF FIGURE 19 3777 G01
Load Step Boost Region Load Step Boost Region Load Step Buck-Boost Region Continuous Mode Pulse-Skipping Mode Continuous Mode
ILOAD ILOAD ILOAD 5A/DIV 5A/DIV 5A/DIV IL I IL 5A/DIV L 5A/DIV 5A/DIV VOUT VOUT VOUT 1V/DIV 1V/DIV 1V/DIV AC-COUPLED AC-COUPLED AC-COUPLED 200µs/DIV 3777 G03 200µs/DIV 3777 G04 200µs/DIV 3777 G05 VIN = 36V VIN = 36V VIN = 48V VOUT = 48V VOUT = 48V VOUT = 48V
Load Step Buck-Boost Region Load Step Buck Region Load Step Buck Region Pulse-Skipping Mode Continuous Mode Pulse-Skipping Mode
ILOAD ILOAD ILOAD 5A/DIV 5A/DIV 5A/DIV IL IL IL 5A/DIV 5A/DIV 5A/DIV VOUT VOUT VOUT 1V/DIV 1V/DIV 1V/DIV AC-COUPLED AC-COUPLED AC-COUPLED 200µs/DIV 3777 G06 200µs/DIV 3777 G07 200µs/DIV 3777 G08 VIN = 48V VIN = 120V VIN = 120V VOUT = 48V VOUT = 48V VOUT = 48V Rev A 6 For more information www.analog.com Document Outline FEATURES DESCRIPTION APPLICATIONS TYPICAL APPLICATION ABSOLUTE MAXIMUM RATINGS PIN CONFIGURATION ORDER INFORMATION ELECTRICAL CHARACTERISTICS TYPICAL PERFORMANCE CHARACTERISTICS TYPICAL PERFORMANCE CHARACTERISTICS – SWITCHING BIAS SUPPLY PIN FUNCTIONS BLOCK DIAGRAM OPERATION APPLICATIONS INFORMATION PACKAGE DESCRIPTION REVISION HISTORY TYPICAL APPLICATION RELATED PARTS