Step-Up Converter
for Handheld Applications
Typical Operating Characteristics
(V = 3.6V, C
IN
= 22µF, X5R, 6.3V local and 10µF, X5R, 6.3V, 1µH inductor, circuit of Figure 1, T = +25NC, unless otherwise noted.)
A
OUT
EFFICIENCY vs. OUTPUT CURRENT
(V = 3.7V)
NO-LOAD SUPPLY CURRENT
vs. INPUT VOLTAGE
EFFICIENCY vs. OUTPUT CURRENT
(V = 5V)
OUT
OUT
80
70
60
50
40
30
20
10
0
100
98
96
94
92
90
88
86
84
82
80
100
95
90
85
80
75
70
65
60
V
= 4.3V
IN
V
V
= 3.1V
= 2.5V
IN
IN
V
= 5V
OUT
V
= 3.1V
IN
V
= 2.5V
V = 3.6V
IN
IN
V
= 3.7V
OUT
L = TOKO DFE252012 1µH
100
L = TOKO DFE252012 1µH
100
2.5
3.0
3.5
4.0
4.5
5.0
5.5
1
10
1000
1
10
1000
INPUT VOLTAGE (V)
LOAD CURRENT (mA)
LOAD CURRENT (mA)
MAXIMUM OUTPUT CURRENT
vs. INPUT VOLTAGE
OUTPUT VOLTAGE (V
= 5V)
OUT
OUTPUT VOLTAGE (V
= 3.7V)
OUT
vs. OUTPUT CURRENT
vs. OUTPUT CURRENT
3000
2500
2000
1500
1000
500
5.05
5.00
4.95
4.90
4.85
4.80
4.75
4.70
4.65
4.60
4.55
4.4
4.2
4.0
3.8
3.6
3.4
3.2
V
, 5V ≥ 4.5V
OUT
V
= 3.6V
IN
V
IN
= 4.3V
V
= 4.3V
IN
V
= 2.5V
IN
V
= 3.2V
IN
V
= 3.2V
IN
V
, 3.7V ≥ 3.35V
OUT
V
= 3.6V
200
IN
V
= 2.5V
800
IN
2.5
3.0
3.5
4.0
4.5
5.0
5.5
0
200
400
600
1000
0
400
600
800
1000
INPUT VOLTAGE (V)
OUTPUT CURRENT (mA)
OUTPUT CURRENT (mA)
OUTPUT VOLTAGE (V
= 3.7V)
OUT
OUTPUT VOLTAGE (V
= 5V)
OUT
vs. INPUT VOLTAGE
vs. INPUT VOLTAGE
5.0
5.5
5.0
4.5
4.0
3.5
3.0
I
= 10mA
I
OUT
OUT
= 100mA
I
OUT
= 600mA
AUTOMATIC
TRACK MODE
TRANSITION
= 100mA
4.5
4.0
3.5
3.0
2.5
I
= 10mA
OUT
I
OUT
AUTOMATIC
FREQUENCY
ADJUSTMENT
I
= 1000mA
OUT
AUTOMATIC
TRACK MODE
TRANSITION
I
= 1000mA
OUT
I
= 600mA
OUT
AUTOMATIC
FREQUENCY
ADJUSTMENT
2.5
3.0
3.5
4.0
4.5
2.5
3.0
3.5
4.0
4.5
5.0
5.5
INPUT VOLTAGE (V)
INPUT VOLTAGE (V)
_______________________________________________________________________________________
5
MAXIM [ MAXIM INTEGRATED PRODUCTS ]
