MAX639 Maxim, MAX639 Datasheet - Page 4

• Manufacturer Part Number: MAX639
• Description: 5V/3.3V/3V/Adjustable / High-Efficiency / Low IQ / Step-Down DC-DC Converters
• Manufacturer: Maxim

5V/3.3V/3V/Adjustable, High-Efficiency,
Low I
4
(Circuit of Figure 3, internal feedback, L = 100µH, T
_____________________________Typical Operating Characteristics (continued)
100
_______________________________________________________________________________________
250
200
150
100
90
80
70
60
50
10
3
L = 100 H
L = 100 H
MAX640
MAXIMUM OUTPUT CURRENT vs.
4
100
5
Q
150
125
100
OUTPUT CURRENT
OUTPUT CURRENT (A)
75
50
25
EFFICIENCY vs.
INPUT VOLTAGE
0
, Step-Down DC-DC Converters
6
3
1m
MAX639
7
V+ (V)
4
OUTPUT VOLTAGE RIPPLE vs.
MAX639, V+ = 6V
MAX640, V+ = 4.3V
MAX653, V+ = 4V
8
10m
5
MAX653
9
INPUT VOLTAGE
L = 220 H
6
L = 100 H
100m
10
MAX640
7
V+ (V)
11
8
1
12
9
I
L = 470 H
OUT
10
= 25mA
11
100
75
65
55
45
35
25
95
90
85
80
A
12
3
3
= +25°C, unless otherwise noted.)
MAXIMUM OUTPUT CURRENT vs.
MAX653
4
4
MAX640
5
5
MAX653
INPUT VOLTAGE
EFFICIENCY vs.
INPUT VOLTAGE
6
6
MAX640
7
7
V+ (V)
V+ (V)
MAX639
8
8
I
OUT
9
9
L = 470µH
= 100mA
MAX639
10
10
150
125
100
75
50
25
0
11
11
3
12
12
4
OUTPUT VOLTAGE RIPPLE vs.
5
L = 470 H
L = 220 H
INPUT VOLTAGE
6
150
125
100
100
75
50
25
95
90
85
80
L = 100 H
MAX653
0
7
V+ (V)
5
3
8
4
OUTPUT VOLTAGE RIPPLE vs.
6
MAX640
9
I
L = 220 H
LOAD
5
L = 470 H
L = 100 H
7
10
INPUT VOLTAGE
INPUT VOLTAGE
INPUT VOLTAGE (V)
EFFICIENCY vs.
= 25mA
6
MAX639
11
8
MAX653
7
V+ (V)
12
8
9
L = 470 H
I
9
I
OUT
OUT
10
= 25mA
10
MAX639
= 25mA
11
11
12
12