Datasheet LTC3868 (Analog Devices) - 5
| Manufacturer | Analog Devices |
| Description | Low IQ, Dual 2-Phase Synchronous Step-Down Controller |
| Pages / Page | 38 / 5 — TYPICAL PERFORMANCE CHARACTERISTICS. Efficiency and Power Loss. vs Output … |
| File Format / Size | PDF / 406 Kb |
| Document Language | English |
TYPICAL PERFORMANCE CHARACTERISTICS. Efficiency and Power Loss. vs Output Current. Efficiency vs Output Current. Load Step
Model Line for this Datasheet
Text Version of Document
LTC3868
TYPICAL PERFORMANCE CHARACTERISTICS Efficiency and Power Loss vs Output Current Efficiency vs Output Current
100 10000 100 FIGURE 12 CIRCUIT 90 V 90 IN = 12V VIN = 5V V 80 OUT = 3.3V 1000 80 POWER LOSS (mW) 70 70 VIN = 12V 60 100 60 50 50 40 10 40 EFFICIENCY (%) EFFICIENCY (%) 30 Burst Mode 30 20 OPERATION 1 20 PULSE- 10 SKIPPING 10 VOUT = 3.3V FCM FIGURE 12 CIRCUIT 0 0.1 0 0.0001 0.001 0.01 0.1 1 10 0.0001 0.001 0.01 0.1 1 10 OUTPUT CURRENT (A) OUTPUT CURRENT (A) 3868 G01 3868 G02
Load Step Efficiency vs Input Voltage Load Step (Burst Mode Operation) (Forced Continuous Mode)
98 FIGURE 12 CIRCUIT 96 VOUT = 3.3V I V OUT = 4A OUT VOUT 94 100mV/DIV 100mV/DIV AC- AC- 92 COUPLED COUPLED 90 88 EFFICIENCY (%) 86 IL 2A/DIV IL 2A/DIV 84 82 80 0 5 10 15 20 25 28 20µs/DIV 3868 G04 VOUT = 3.3V 20µs/DIV 3868 G05 VOUT = 3.3V INPUT VOLTAGE (V) FIGURE 12 CIRCUIT FIGURE 12 CIRCUIT 3868 G03
Load Step (Pulse-Skipping Mode) Inductor Current at Light Load Soft Start-Up
VOUT FORCED V 100mV/DIV OUT2 CONTINUOUS 2V/DIV AC- MODE COUPLED Burst Mode V OPERATION OUT1 2V/DIV 2A/DIV IL 2A/DIV PULSE- SKIPPING MODE 20µs/DIV 3868 G06 VOUT = 3.3V 2µs/DIV 3868 G07 VOUT = 3.3V 20ms/DIV 3868 G08 FIGURE 12 CIRCUIT ILOAD = 200µA FIGURE 12 CIRCUIT FIGURE 12 CIRCUIT 3868fe For more information www.linear.com/LTC3868 5 Document Outline Features Description Applications Typical Application Absolute Maximum Ratings Pin Configuration Typical Performance Characteristics Pin Functions Operation Package Description Typical Application Related Parts
TYPICAL PERFORMANCE CHARACTERISTICS Efficiency and Power Loss vs Output Current Efficiency vs Output Current
100 10000 100 FIGURE 12 CIRCUIT 90 V 90 IN = 12V VIN = 5V V 80 OUT = 3.3V 1000 80 POWER LOSS (mW) 70 70 VIN = 12V 60 100 60 50 50 40 10 40 EFFICIENCY (%) EFFICIENCY (%) 30 Burst Mode 30 20 OPERATION 1 20 PULSE- 10 SKIPPING 10 VOUT = 3.3V FCM FIGURE 12 CIRCUIT 0 0.1 0 0.0001 0.001 0.01 0.1 1 10 0.0001 0.001 0.01 0.1 1 10 OUTPUT CURRENT (A) OUTPUT CURRENT (A) 3868 G01 3868 G02
Load Step Efficiency vs Input Voltage Load Step (Burst Mode Operation) (Forced Continuous Mode)
98 FIGURE 12 CIRCUIT 96 VOUT = 3.3V I V OUT = 4A OUT VOUT 94 100mV/DIV 100mV/DIV AC- AC- 92 COUPLED COUPLED 90 88 EFFICIENCY (%) 86 IL 2A/DIV IL 2A/DIV 84 82 80 0 5 10 15 20 25 28 20µs/DIV 3868 G04 VOUT = 3.3V 20µs/DIV 3868 G05 VOUT = 3.3V INPUT VOLTAGE (V) FIGURE 12 CIRCUIT FIGURE 12 CIRCUIT 3868 G03
Load Step (Pulse-Skipping Mode) Inductor Current at Light Load Soft Start-Up
VOUT FORCED V 100mV/DIV OUT2 CONTINUOUS 2V/DIV AC- MODE COUPLED Burst Mode V OPERATION OUT1 2V/DIV 2A/DIV IL 2A/DIV PULSE- SKIPPING MODE 20µs/DIV 3868 G06 VOUT = 3.3V 2µs/DIV 3868 G07 VOUT = 3.3V 20ms/DIV 3868 G08 FIGURE 12 CIRCUIT ILOAD = 200µA FIGURE 12 CIRCUIT FIGURE 12 CIRCUIT 3868fe For more information www.linear.com/LTC3868 5 Document Outline Features Description Applications Typical Application Absolute Maximum Ratings Pin Configuration Typical Performance Characteristics Pin Functions Operation Package Description Typical Application Related Parts
