Datasheet

4
LTC3251/
LTC3251-1.2/LTC3251-1.5
32511215fb
1.5V Output Voltage vs Supply
Voltage (Burst Mode Operation/
Continuous Mode)
V
IN
(V)
3
V
OUT
(V)
1.52
1.56
1.60
5
3251 G04
1.48
1.44
1.50
1.54
1.58
1.46
1.42
1.40
3.5
4
4.5
5.5
I
OUT
= 0mA
I
OUT
= 250mA
I
OUT
= 500mA
T
A
= 25°C
1.2V Output Voltage vs Supply
Voltage (Burst Mode Operation/
Continuous Mode)
V
IN
(V)
2.7
1.300
1.260
1.220
1.180
1.140
1.280
1.240
1.200
1.160
1.120
1.100
4.2 5.2
3251 G05
3.2 3.7
4.7
V
OUT
(V)
I
OUT
= 0mA
I
OUT
= 500mA
I
OUT
= 250mA
T
A
= 25°C
1.5V Output Voltage
vs Supply Voltage
(Super Burst Mode Operation)
V
IN
(V)
3
V
OUT
(V)
1.52
1.56
1.60
5
3251 G06
1.48
1.44
1.50
1.54
1.58
1.46
1.42
1.40
3.5
4
4.5
5.5
T
A
= 25°C 0mA
10mA
40mA
FB Voltage vs Output Current
(Burst Mode Operation/
Continuous Mode)
1.5V Output Efficiency vs Output
Current (Burst Mode Operation)
I
OUT
(mA)
0
0.780
V
FB
(V)
0.785
0.790
0.795
0.800
0.805
100
200 300 400
3251 G07
500 600
T
A
= 25°C
V
OUT
= 1.5V
I
OUT
(mA)
0.1
0
EFFICIENCY (%)
10
30
40
50
100
70
1
10
3251 G08
20
80
90
60
100
1000
V
IN
= 3.3V
MD0 = V
IN
, MD1 = 0V
V
IN
= 4V
V
IN
= 5V
V
IN
= 3.6V
1.5V Output Efficiency vs Output
Current (Super Burst Mode
Operation)
I
OUT
(mA)
0.1
0
EFFICIENCY (%)
10
30
40
50
100
70
1
10
3251 G09
20
80
90
60
100
V
IN
= 3.3V
V
IN
= 4V
V
IN
= 5V
V
IN
= 3.6V
MD0 = MD1 = V
IN
TYPICAL PERFOR A CE CHARACTERISTICS
UW
No Load Supply Current
vs Supply Voltage
(Super Burst Mode Operation)
V
IN
(V)
2.7
20
16
12
8
4
18
14
10
6
2
0
4.2 5.2
3251 G02
3.2 3.7
4.7
I
CC
(µA)
85°C
25°C
–40°C
1.2V Output Voltage
vs Supply Voltage
(Super Burst Mode Operation)
1.2V Output Efficiency vs Output
Current (Burst Mode Operation)
V
IN
(V)
2.7
1.30
1.28
1.26
1.24
1.22
1.20
1.18
1.16
1.14
1.12
1.10
4.2 5.2
3251 G18
3.2 3.7
4.7
V
OUT
(V)
0mA
10mA
40mA
T
A
= 25°C
I
OUT
(mA)
0.1
100
80
60
40
20
90
70
50
30
10
0
10 1000
3251 G19
1
100
EFFICIENCY (%)
V
IN
= 2.7V
V
IN
= 3.5V
V
IN
= 4.5V
V
IN
= 3V
MD0 = V
IN
, MD1 = 0V