Datasheet LTC3897 (Analog Devices) - 7

LTC3897
TYPICAL PERFORMANCE CHARACTERISTICS TA = 25°C unless otherwise noted. Efficiency and Power Loss Efficiency and Power Loss vs Output Current vs Output Current
100 100k 100 100k BURST EFFICIENCY BURST EFFICIENCY 90 90 80 FCM LOSS 10k 80 10k POWER LOSS (mW) POWER LOSS (mW) 70 70 PULSE–SKIPPING 60 LOSS 1k 60 1k BURST LOSS BURST LOSS 50 50 PULSE–SKIPPING 40 EFFICIENCY FCM EFFICIENCY 100 40 100 EFFICIENCY (%) EFFICIENCY (%) 30 30 VIN = 12V 20 V 10 20 V 10 IN = 12V OUT = 24V 10 V Burst Mode OPERATION OUT = 24V 10 FIGURE 17 CIRCUIT FIGURE 17 CIRCUIT 0 1 0 1 0.001 0.01 0.1 1 10 0.001 0.01 0.1 1 10 OUTPUT CURRENT (A) OUTPUT CURRENT (A) 3897 G01 3897 G02
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 3897 G04 INPUT VOLTAGE (V) VOUT = 24V 3897 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 3897 G05 VIN = 12V 200µs/DIV 3897 G06 VOUT = 24V VOUT = 24V LOAD STEP FROM 100mA TO 5A LOAD STEP FROM 100mA TO 5A FIGURE 17 CIRCUIT FIGURE 17 CIRCUIT Rev. A For more information www.analog.com 7 Document Outline Features Applications Typical Application Description Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Typical Application Related Parts