Datasheet LTC3520 (Analog Devices) - 5
| Manufacturer | Analog Devices |
| Description | Synchronous 1A Buck-Boost and 600mA Buck Converters |
| Pages / Page | 24 / 5 — TYPICAL PERFORMANCE CHARACTERISTICS. Buck Effi ciency Lithium-Ion to 1.8V. … |
| File Format / Size | PDF / 324 Kb |
| Document Language | English |
TYPICAL PERFORMANCE CHARACTERISTICS. Buck Effi ciency Lithium-Ion to 1.8V. Switching Frequency vs RT. LDO Load. Buck-Boost Load
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LTC3520
TYPICAL PERFORMANCE CHARACTERISTICS Buck Effi ciency Lithium-Ion to 1.8V Switching Frequency vs RT
100 800 10000 Burst Mode 90 OPERATION 700 PWM MODE 80 600 POWER LOSS (mW) 70 V 60 IN = 4.2V 500 VIN = 3V 50 400 1000 40 300 EFFICIENCY (%) 30 Burst Mode 200 20 OPERATION L = SUMIDA SWITCHING FREQUENCY (kHz) POWER LOSS 10 CDRH3D16NP-4R7N 100 RBURST = 249k 0 0 100 1 10 100 1000 10 100 1000 LOAD CURRENT (mA) RT (k) 3520 G03 3520 G04
LDO Load Buck-Boost Load Transient Response Transient Response
LDO V V OUT OUT 100mV/DIV VIN = 5V 200mV/DIV VOUT VIN = 2.2V 500mV/DIV LOAD CURRENT 100mA/DIV LOAD CURRENT (20mA TO 500mA/DIV 210mA STEP) 3520 G05 50μs/DIV 3520 G06 200μs/DIV V C IN = 3.6V COUT = 4.7μF OUT = 47μF V L = 4.7μH OUT = 1.5V LDO INPUT VOLTAGE = 1.8V VIN = 3.3V
Buck Load Transient Buck Load Transient Response (PWM Mode) Response (Burst Mode Operation)
BUCK VOUT BUCK VOUT 100mV/DIV 100mV/DIV LOAD CURRENT LOAD CURRENT 500mA/DIV 200mA/DIV (50mA TO (5mA TO 500mA STEP) 300mA STEP) 3520 G07 3520 G08 100μs/DIV 100μs/DIV VIN = 3.6V V C V IN = 3.6V OUT = 22μF OUT = 1.8V V R C OUT = 1.8V BURST = 249k OUT = 10μF 3520fa 5
TYPICAL PERFORMANCE CHARACTERISTICS Buck Effi ciency Lithium-Ion to 1.8V Switching Frequency vs RT
100 800 10000 Burst Mode 90 OPERATION 700 PWM MODE 80 600 POWER LOSS (mW) 70 V 60 IN = 4.2V 500 VIN = 3V 50 400 1000 40 300 EFFICIENCY (%) 30 Burst Mode 200 20 OPERATION L = SUMIDA SWITCHING FREQUENCY (kHz) POWER LOSS 10 CDRH3D16NP-4R7N 100 RBURST = 249k 0 0 100 1 10 100 1000 10 100 1000 LOAD CURRENT (mA) RT (k) 3520 G03 3520 G04
LDO Load Buck-Boost Load Transient Response Transient Response
LDO V V OUT OUT 100mV/DIV VIN = 5V 200mV/DIV VOUT VIN = 2.2V 500mV/DIV LOAD CURRENT 100mA/DIV LOAD CURRENT (20mA TO 500mA/DIV 210mA STEP) 3520 G05 50μs/DIV 3520 G06 200μs/DIV V C IN = 3.6V COUT = 4.7μF OUT = 47μF V L = 4.7μH OUT = 1.5V LDO INPUT VOLTAGE = 1.8V VIN = 3.3V
Buck Load Transient Buck Load Transient Response (PWM Mode) Response (Burst Mode Operation)
BUCK VOUT BUCK VOUT 100mV/DIV 100mV/DIV LOAD CURRENT LOAD CURRENT 500mA/DIV 200mA/DIV (50mA TO (5mA TO 500mA STEP) 300mA STEP) 3520 G07 3520 G08 100μs/DIV 100μs/DIV VIN = 3.6V V C V IN = 3.6V OUT = 22μF OUT = 1.8V V R C OUT = 1.8V BURST = 249k OUT = 10μF 3520fa 5
