1- to 3-Cell, High-Current, Low-Noise,
Step-Up DC-DC Converters with Linear Regulator
MAX1705/MAX1706
__________________________________________Typical Operating Characteristics
(Circuit of Figure 2, T
A
= +25°C, unless otherwise noted.)
MAX1705
EFFICIENCY vs. OUTPUT CURRENT
(V
OUT
= 3.3V)
MAX1705/6 TOC01
MAX1705
EFFICIENCY vs. OUTPUT CURRENT
(V
OUT
= 5V)
MAX1705/6 TOC02
MAX1705
MAXIMUM OUTPUT CURRENT
vs. INPUT VOLTAGE
900
MAXIMUM OUTPUT CURRENT (mA)
800
700
600
500
400
300
200
100
0
1000
0
V
OUT
= 5V
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5
INPUT VOLTAGE (V)
PFM MODE
V
OUT
= 3.3V
V
OUT
= 3.3V
V
OUT
= 5V
L = 10µH
MAX1705/6 TOC03
100
90
80
EFFICIENCY (%)
70
60
50
40
30
20
10
0
0.1
1
10
100
L = 10µH
V
OUT
= 3.3V
A: V
IN
= 0.9V
B: V
IN
= 2.7V
1: PFM MODE
2: PWM MODE
A.2
B.1
A.1
B.2
100
90
80
EFFICIENCY (%)
70
60
50
40
30
20
10
0
A.1
L = 10µH
V
OUT
= 5V
A: V
IN
= 0.9V
C: V
IN
= 2.4V
E: V
IN
= 3.6V
1: PFM MODE
2: PWM MODE
0.1
1
10
100
B.1
A.2
C.1
B.2 C.2
1000
PWM MODE
1000
OUTPUT CURRENT (mA)
OUTPUT CURRENT (mA)
MAX1706
EFFICIENCY vs. OUTPUT CURRENT
(V
OUT
= 3.3V)
MAX1705/6 TOC04
MAX1706
EFFICIENCY vs. OUTPUT CURRENT
(V
OUT
= 5V)
MAX1705/6 TOC05
MAX1706
MAXIMUM OUTPUT CURRENT
vs. INPUT VOLTAGE
L = 22µH
MAXIMUM OUTPUT CURRENT (mA)
600
500
400
300
200
100
0
V
OUT
= 3.3V
V
OUT
= 5V
PFM MODE
0
0.5 1.0 1.5 2.0 2.5
3
3.5
4
4.5
PWM MODE
V
OUT
= 5V
V
OUT
= 3.3V
MAX1705/6 TOC06
100
90
80
EFFICIENCY (%)
70
60
50
40
30
20
10
0
0.1
1
10
100
L = 22µH
V
OUT
= 3.3V
A: V
IN
= 0.9V
B: V
IN
= 2.7V
1: PFM MODE
2: PWM MODE
A.1
A.2
B.1
B.2
100
90
80
EFFICIENCY (%)
70
60
50
40
30
20
10
0
0.1
1
10
A.1
B.1
A.2
L = 22µH
V
OUT
= 5V
A: V
IN
= 0.9V
B: V
IN
= 2.4V
C: V
IN
= 3.6V
1: PFM MODE
2: PWM MODE
100
C.1
B.2 C.2
700
1000
1000
OUTPUT CURRENT (mA)
OUTPUT CURRENT (mA)
INPUT VOLTAGE (V)
MAX1705
START-UP INPUT VOLTAGE
vs. OUTPUT CURRENT
MAX1705/6 TOC07
NO-LOAD SUPPLY CURRENT
vs. INPUT VOLTAGE
11
10
9
8
7
6
5
4
3
2
1
0
0
PWM MODE
V
OUT
= 3.3V
L = 10µH
MAX1705/6 TOC8
LINEAR-REGULATOR DROPOUT
VOLTAGE vs. LOAD CURRENT
V
LDO
= 3.3V
MAX1705/6 TOC09
2.3
2.1
START-UP INPUT VOLTAGE (V)
1.9
1.7
1.5
1.3
1.1
0.9
0.7
0.5
0.01
0.1
1
10
100
NO-LOAD START-UP:
1.0V AT -40°C
0.79 AT +25°C
0.64V AT +85°C
CONSTANT-CURRENT LOAD
V
OUT
= 3.3V
L = 10µH
D1 = MBR0520L
T
A
= -40°C
T
A
= +25°C
T
A
= +85°C
12
NO-LOAD SUPPLY CURRENT (mA)
140
120
DROPOUT VOLTAGE (mV)
100
80
60
V
LDO
= 5V
40
20
V
LDO
= 2.5V
PFM MODE
0
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0
INPUT VOLTAGE (V)
0
40
80
120
160
200
LOAD CURRENT (mA)
1000
OUTPUT CURRENT (mA)
6
_______________________________________________________________________________________
MAXIM [ MAXIM INTEGRATED PRODUCTS ]
