Datasheet

LTC3539/LTC3539-2
4
35392fb
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0.7 1.5 2.31.1 1.9 3.1 5.13.9 4.3 4.72.7 3.5
V
IN
(V)
I
OUT
(mA)
2000
200
1800
1400
1000
600
1600
1200
800
400
0
3539 G05
V
OUT
= 1.8V
V
OUT
= 2.5V
V
OUT
= 3.3V
V
OUT
= 5V
L = 2.2µH
V
IN
(V)
INPUT CURRENT (µA)
200
20
180
140
100
60
160
120
80
40
0
3539 G04
V
OUT
= 1.8V
V
OUT
= 2.5V
V
OUT
= 3.3V
V
OUT
= 5V
0 2 41 3 5
Typical perForMance characTerisTics
Efficiency vs Load Current and
V
IN
, V
OUT
= 5V No Load Input Current vs V
IN
Maximum Output Current vs V
IN
0.1
1
10
100
1000
POWER LOSS (mW)
LOAD CURRENT (mA)
EFFICIENCY (%)
100
10
90
70
50
30
80
60
40
20
0
3539 G03
V
IN
= 2.4V
V
IN
= 3.6V
V
IN
= 4.2V
POWER LOSS
EFFICIENCY
0.1 100 1000101
Minimum Load Resistance During
Start-Up vs V
IN
Burst Mode Threshold Current
vs V
IN
; V
OUT
= 1.8V
0.65 0.85 1.050.75 0.95 1.15
V
IN
(V)
LOAD RESISTANCE (Ω)
3539 G06
10000
1000
100
10
0.1
V
OUT
= 3.3V
(T
A
= 25°C unless otherwise noted)
Normalized Current Limit vs V
OUT
V
OUT
(V)
NORMALIZED CURRENT LIMIT (A)
1.10
1.05
0.95
0.85
1.00
0.90
0.80
3539 G08
1.0 1.5 2.52.0 3.5 5.04.53.0 4.0
0.7 0.8 0.9 1 1.1 1.2 1.3 1.51.4
V
IN
(V)
LOAD CURRENT (mA)
50
5
45
35
25
15
40
30
20
10
0
3539 G07a
C
OUT
= 44µF
f
SW
= 1MHz
f
SW
= 2MHz
ENTER BURST
LEAVE BURST
0.7 0.9 1.1 1.3 1.5 1.7 1.9 2.1
V
IN
(V)
LOAD CURRENT (mA)
50
5
45
35
25
15
40
30
20
10
0
3539 G07b
C
OUT
= 44µF
f
SW
= 1MHz
f
SW
= 2MHz
ENTER BURST
LEAVE BURST
0.7 0.9 1.1 1.3 1.5 1.7 1.9 2.72.3 2.52.1
V
IN
(V)
LOAD CURRENT (mA)
10
50
30
60
40
20
0
3539 G07c
C
OUT
= 44µF
f
SW
= 1MHz
f
SW
= 2MHz
ENTER BURST
LEAVE BURST
0.7 1.1 1.5 1.9 2.3 2.7 3.1 4.33.93.5
V
IN
(V)
LOAD CURRENT (mA)
100
10
90
70
50
30
80
60
40
20
0
3539 G07d
C
OUT
= 44µF
f
SW
= 1MHz
f
SW
= 2MHz
ENTER BURST
LEAVE BURST
Burst Mode Threshold Current
vs V
IN
; V
OUT
= 2.5V
Burst Mode Threshold Current
vs V
IN
; V
OUT
= 3.3V
Burst Mode Threshold Current
vs V
IN
; V
OUT
= 5V