Datasheet LTC3568 (Analog Devices) - 4
| Manufacturer | Analog Devices |
| Description | 1.8A, 4MHz, Synchronous Step-Down DC/DC Converter |
| Pages / Page | 18 / 4 — Burst Mode Operation. Pulse Skipping Mode. Forced Continuous Mode. … |
| File Format / Size | PDF / 313 Kb |
| Document Language | English |
Burst Mode Operation. Pulse Skipping Mode. Forced Continuous Mode. Efficiency vs Load Current. Efficiency vs VIN. Load Step
Model Line for this Datasheet
Text Version of Document
LTC3568 Typical perForMance characTerisTics
Burst Mode Operation Pulse Skipping Mode Forced Continuous Mode
V V V OUT OUT OUT 10mV/ 10mV/ 10mV/ DIV DIV DIV SW SW S 2V/DIV 2V/DIV W 2V/DIV IL IL 500mA/ 200mA/ IL DIV DIV 500mA/ DIV VIN = 3.3V 10µs/DIV 3568 G01 VIN = 3.3V 2µs/DIV 3568 G02 VIN = 3.3V 2µs/DIV 3568 G03 VOUT = 2.5V VOUT = 2.5V VOUT = 2.5V ILOAD = 100mA ILOAD = 100mA ILOAD = 100mA
Efficiency vs Load Current Efficiency vs VIN Load Step
100 100 Burst Mode IOUT = 500mA OPERATION 95 95 VOUT 100mV/ 90 DIV 90 IOUT = 1.8A 85 85 80 EFFICIENCY (%) 75 80 EFFICIENCY (%) IL PULSE SKIP FORCED CONTINUOUS 1A/ 70 DIV 75 VIN = 3.3V V 65 OUT = 2.5V VOUT = 2.5V VIN = 3.3V 50µs/DIV 3568 G06 CIRCUIT OF FIGURE 7 CIRCUIT OF FIGURE 7 VOUT = 2.5V 70 60 I 1 10 100 1000 10000 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 LOAD = 180mA TO 1.8A LOAD CURRENT (mA) VIN (V) 3568 G04 3568 G05
Load Regulation Line Regulation Frequency vs VIN
0.6 0.20 10 VIN = 3.3V VOUT = 1.8V VOUT = 1.8V 0.5 V 8 I Burst Mode OUT = 1.8V 0.15 OUT = 1.25A 0.4 T OPERATION 6 A = 25°C 0.10 0.3 4 PULSE SKIP IOUT = 1.8A 0.2 0.05 2 0.1 0 IOUT = 500mA 0 ERROR (%) 0 FORCED ERROR (%) –0.05 –2 V OUT CONTINUOUS –0.1 V OUT –4 –0.10 –0.2 FREQUENCY VARIATION (%) –6 –0.3 –0.15 –8 –0.4 –0.20 –10 1 10 100 1000 10000 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 2 3 4 5 6 LOAD CURRENT (mA) VIN (V) VIN (V) 3568 G07 3568 G08 3568 G09 3568fa Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Revision History Typical Application Related Parts
Burst Mode Operation Pulse Skipping Mode Forced Continuous Mode
V V V OUT OUT OUT 10mV/ 10mV/ 10mV/ DIV DIV DIV SW SW S 2V/DIV 2V/DIV W 2V/DIV IL IL 500mA/ 200mA/ IL DIV DIV 500mA/ DIV VIN = 3.3V 10µs/DIV 3568 G01 VIN = 3.3V 2µs/DIV 3568 G02 VIN = 3.3V 2µs/DIV 3568 G03 VOUT = 2.5V VOUT = 2.5V VOUT = 2.5V ILOAD = 100mA ILOAD = 100mA ILOAD = 100mA
Efficiency vs Load Current Efficiency vs VIN Load Step
100 100 Burst Mode IOUT = 500mA OPERATION 95 95 VOUT 100mV/ 90 DIV 90 IOUT = 1.8A 85 85 80 EFFICIENCY (%) 75 80 EFFICIENCY (%) IL PULSE SKIP FORCED CONTINUOUS 1A/ 70 DIV 75 VIN = 3.3V V 65 OUT = 2.5V VOUT = 2.5V VIN = 3.3V 50µs/DIV 3568 G06 CIRCUIT OF FIGURE 7 CIRCUIT OF FIGURE 7 VOUT = 2.5V 70 60 I 1 10 100 1000 10000 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 LOAD = 180mA TO 1.8A LOAD CURRENT (mA) VIN (V) 3568 G04 3568 G05
Load Regulation Line Regulation Frequency vs VIN
0.6 0.20 10 VIN = 3.3V VOUT = 1.8V VOUT = 1.8V 0.5 V 8 I Burst Mode OUT = 1.8V 0.15 OUT = 1.25A 0.4 T OPERATION 6 A = 25°C 0.10 0.3 4 PULSE SKIP IOUT = 1.8A 0.2 0.05 2 0.1 0 IOUT = 500mA 0 ERROR (%) 0 FORCED ERROR (%) –0.05 –2 V OUT CONTINUOUS –0.1 V OUT –4 –0.10 –0.2 FREQUENCY VARIATION (%) –6 –0.3 –0.15 –8 –0.4 –0.20 –10 1 10 100 1000 10000 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 2 3 4 5 6 LOAD CURRENT (mA) VIN (V) VIN (V) 3568 G07 3568 G08 3568 G09 3568fa Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Typical Applications Package Description Revision History Typical Application Related Parts
