Datasheet LTC3897-2 (Analog Devices) - 7

LTC3897-2
TYPICAL PERFORMANCE CHARACTERISTICS TA = 25°C unless otherwise noted. Load Step Efficiency vs Input Current Forced Continuous Mode
100 99 98 LOAD STEP 97 5A/DIV 96 95 94 93 INDUCTOR 92 CURRENT 91 5A/DIV EFFICIENCY (%) 90 89 88 VOUT I 87 OUT = 2A 500mV/DIV V 86 OUT = 24V FIGURE 17 CIRCUIT 85 0 5 10 15 20 25 VIN = 12V 200µs/DIV 38972 G04 INPUT VOLTAGE (V) VOUT = 24V 38972 G03 LOAD STEP FROM 100mA TO 5A FIGURE 17 CIRCUIT
Load Step Load Step Burst Mode Operation Pulse-Skipping Mode
LOAD STEP LOAD STEP 5A/DIV 5A/DIV INDUCTOR CURRENT INDUCTOR 5A/DIV CURRENT 5A/DIV VOUT V 500mV/DIV OUT 500mV/DIV VIN = 12V 200µs/DIV 38972 G05 VIN = 12V 200µs/DIV 38972 G06 VOUT = 24V VOUT = 24V LOAD STEP FROM 100mA TO 5A LOAD STEP FROM 100mA TO 5A FIGURE 17 CIRCUIT FIGURE 17 CIRCUIT
Inductor Currents at Light Load Start-Up
VOUT FORCED CONTINUOUS MODE SG Burst Mode VOUT OPERATION 10V/DIV VIN 5A/DIV PULSE- SKIPPING CS MODE 0V VIN = 12V 5µs/DIV 38972 G07 VIN = 12V 10ms/DIV 38972 G08 VOUT = 24V VOUT = 48V ILOAD = 200µA FIGURE 16 CIRCUIT FIGURE 17 CIRCUIT Rev. A For more information www.analog.com 7 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Order Information Pin Configuration Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Typical Application Related Parts