Datasheet LTC3853 (Analog Devices) - 5
| Manufacturer | Analog Devices |
| Description | Triple Output, Multiphase Synchronous Step-Down Controller |
| Pages / Page | 36 / 5 — TYPICAL PERFORMANCE CHARACTERISTICS. Efficiency vs Output Current. … |
| File Format / Size | PDF / 763 Kb |
| Document Language | English |
TYPICAL PERFORMANCE CHARACTERISTICS. Efficiency vs Output Current. Efficiency and Power Loss. and Mode. vs Input Voltage
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LTC3853
TYPICAL PERFORMANCE CHARACTERISTICS Efficiency vs Output Current Efficiency vs Output Current Efficiency and Power Loss and Mode and Mode vs Input Voltage
100 100 100 2.0 90 90 95 1.8 80 80 1.6 BURST 90 POWER LOSS (mW) EFFICIENCY 70 70 1.4 BURST 85 60 60 1.2 50 50 80 1.0 DCM CCM CCM 40 40 DCM POWER LOSS 0.8 EFFICIENCY (%) EFFICIENCY (%) EFFICIENCY (%) 75 30 30 0.6 70 VIN = 12V VIN = 12V VOUT = 3.3V 20 20 0.4 VOUT = 1.8V VOUT = 3.3V I FIGURE 15 MODIFIED FIGURE 15 MODIFIED 65 OUT = 2A 10 10 FIGURE 15 MODIFIED 0.2 WITH DCR SENSING WITH DCR SENSING WITH DCR SENSING 0 0 60 0 0.01 0.1 1 10 0.01 0.1 1 10 0 5 10 15 20 25 30 LOAD CURRENT (A) LOAD CURRENT (A) INPUT VOLTAGE (V) 3853 G01 3853 G02 3853 G03
Load Step Load Step (Burst Mode Operation) (Forced Continuous Mode)
I I LOAD LOAD 2A/DIV 2A/DIV IL IL 2A/DIV 2A/DIV VOUT VOUT 100mV/DIV 100mV/DIV AC COUPLED AC COUPLED 40µs/DIV 3853 G04 V 3853 G05 IN = 12V VIN = 12V 40µs/DIV VOUT = 3.3V VOUT = 3.3V ILOAD = 0A TO 3A ILOAD = 0A TO 3A FIGURE 15 CIRCUIT FIGURE 15 CIRCUIT
Load Step (Pulse Skip Mode) Inductor Current at Light Load
ILOAD FORCED 2A/DIV CONTINUOUS MODE 2A/DIV IL Burst Mode 2A/DIV OPERATION 2A/DIV VOUT 100mV/DIV PULSE SKIPPING AC COUPLED MODE 2A/DIV 40µs/DIV 3853 G06 V 3853 G07 IN = 12V VIN = 12V 1µs/DIV VOUT = 3.3V VOUT = 1.8V ILOAD = 0A TO 3A ILOAD = 100mA FIGURE 15 CIRCUIT FIGURE 15 CIRCUIT 3853fc For more information www.linear.com/LTC3853 5 Document Outline Features Typical Application Description Absolute Maximum Ratings Order Information Pin Configuration Electrical Characteristics Typical Performance Characteristics Pin Functions Functional Diagram Operation Applications Information Typical Applications Package Description Revision History Typical Application Related Parts
TYPICAL PERFORMANCE CHARACTERISTICS Efficiency vs Output Current Efficiency vs Output Current Efficiency and Power Loss and Mode and Mode vs Input Voltage
100 100 100 2.0 90 90 95 1.8 80 80 1.6 BURST 90 POWER LOSS (mW) EFFICIENCY 70 70 1.4 BURST 85 60 60 1.2 50 50 80 1.0 DCM CCM CCM 40 40 DCM POWER LOSS 0.8 EFFICIENCY (%) EFFICIENCY (%) EFFICIENCY (%) 75 30 30 0.6 70 VIN = 12V VIN = 12V VOUT = 3.3V 20 20 0.4 VOUT = 1.8V VOUT = 3.3V I FIGURE 15 MODIFIED FIGURE 15 MODIFIED 65 OUT = 2A 10 10 FIGURE 15 MODIFIED 0.2 WITH DCR SENSING WITH DCR SENSING WITH DCR SENSING 0 0 60 0 0.01 0.1 1 10 0.01 0.1 1 10 0 5 10 15 20 25 30 LOAD CURRENT (A) LOAD CURRENT (A) INPUT VOLTAGE (V) 3853 G01 3853 G02 3853 G03
Load Step Load Step (Burst Mode Operation) (Forced Continuous Mode)
I I LOAD LOAD 2A/DIV 2A/DIV IL IL 2A/DIV 2A/DIV VOUT VOUT 100mV/DIV 100mV/DIV AC COUPLED AC COUPLED 40µs/DIV 3853 G04 V 3853 G05 IN = 12V VIN = 12V 40µs/DIV VOUT = 3.3V VOUT = 3.3V ILOAD = 0A TO 3A ILOAD = 0A TO 3A FIGURE 15 CIRCUIT FIGURE 15 CIRCUIT
Load Step (Pulse Skip Mode) Inductor Current at Light Load
ILOAD FORCED 2A/DIV CONTINUOUS MODE 2A/DIV IL Burst Mode 2A/DIV OPERATION 2A/DIV VOUT 100mV/DIV PULSE SKIPPING AC COUPLED MODE 2A/DIV 40µs/DIV 3853 G06 V 3853 G07 IN = 12V VIN = 12V 1µs/DIV VOUT = 3.3V VOUT = 1.8V ILOAD = 0A TO 3A ILOAD = 100mA FIGURE 15 CIRCUIT FIGURE 15 CIRCUIT 3853fc For more information www.linear.com/LTC3853 5 Document Outline Features Typical Application Description Absolute Maximum Ratings Order Information Pin Configuration Electrical Characteristics Typical Performance Characteristics Pin Functions Functional Diagram Operation Applications Information Typical Applications Package Description Revision History Typical Application Related Parts
