Datasheet

LTC3520
5
3520fa
TYPICAL PERFORMANCE CHARACTERISTICS
Buck Effi ciency
Lithium-Ion to 1.8V Switching Frequency vs R
T
LDO Load
Transient Response
Buck-Boost Load
Transient Response
Buck Load Transient
Response (PWM Mode)
Buck Load Transient
Response (Burst Mode Operation)
LOAD CURRENT (mA)
1
0
EFFICIENCY (%)
POWER LOSS (mW)
10
30
40
50
100
70
10
100
20
80
90
60
0
100
300
400
500
800
700
200
600
1000
3520 G03
V
IN
= 4.2V
V
IN
= 3V
PWM MODE
Burst Mode
OPERATION
Burst Mode
OPERATION
POWER LOSS
L = SUMIDA
CDRH3D16NP-4R7N
R
BURST
= 249k
R
T
(k)
10
100
SWITCHING FREQUENCY (kHz)
1000
10000
100 1000
3520 G04
50μs/DIV
LDO V
OUT
100mV/DIV
LOAD
CURRENT
100mA/DIV
(20mA TO
210mA STEP)
3520 G05
V
IN
= 3.6V
V
OUT
= 1.5V
C
OUT
= 4.7μF
LDO INPUT VOLTAGE = 1.8V
200μs/DIV
V
OUT
V
IN
= 5V
200mV/DIV
V
OUT
V
IN
= 2.2V
500mV/DIV
LOAD CURRENT
500mA/DIV
C
OUT
= 47μF
L = 4.7μH
V
IN
= 3.3V
3520 G06
100μs/DIV
BUCK V
OUT
100mV/DIV
LOAD CURRENT
500mA/DIV
(50mA TO
500mA STEP)
3520 G07
V
IN
= 3.6V
V
OUT
= 1.8V
C
OUT
= 10μF
100μs/DIV
BUCK V
OUT
100mV/DIV
LOAD CURRENT
200mA/DIV
(5mA TO
300mA STEP)
3520 G08
V
IN
= 3.6V
V
OUT
= 1.8V
C
OUT
= 22μF
R
BURST
= 249k