Typical operating characteristics – Rainbow Electronics MAX1677 User Manual
Page 5
MAX1677
Compact, High-Efficiency, Dual-Output
Step-Up and LCD Bias DC-DC Converter
_______________________________________________________________________________________
5
0.1
10
1
100
1000
EFFICIENCY vs. LOAD CURRENT
(V
OUT
= 3.3V)
MAX1677-01
LOAD CURRENT (mA)
EFFICIENCY (%)
100
60
70
80
90
PWM MODE
C = 2.4V
D = 1.2V
PFM MODE
A = V
IN
= 2.4V
B = V
IN
= 1.2V
C
D
B
A
100
80
60
40
20
0
0.1
1
10
100
1000
EFFICIENCY vs. LOAD CURRENT
(V
OUT
= 5V)
MAX1677-02
LOAD CURRENT (mA)
EFFICIENCY (%)
PWM MODE
A: V
IN
= 3.6V
B: V
IN
= 2.4V
C: V
IN
= 1.2V
A
D
E
F
B
C
PFM MODE
D: V
IN
= 3.6V
E: V
IN
= 2.4V
F: V
IN
= 1.2V
0
100
300
200
500
600
400
700
0
1.0
1.5
0.5
2.0
2.5
3.0
3.5
4.0
MAXIMUM LOAD CURRENT
vs. BATTERY INPUT VOLTAGE
(PWM MODE)
MAX1677-03
INPUT VOLTAGE (V)
LOAD CURENT (mA)
V
OUT
= 3.3V
V
OUT
= 5V
40
0.1
100
10
1
EFFICIENCY vs. LOAD CURRENT
(LCD V
OUT
= 12V)
100
60
50
80
90
70
MAX1677-04
LOAD CURRENT (mA)
EFFICIENCY (%)
CIRCUIT OF FIGURE 2
A: V
IN
= 3.6V
B: V
IN
= 2.4V
C: V
IN
= 1.2V
A
B
C
50
0.1
100
10
1
EFFICIENCY vs. LOAD CURRENT
(LCD V
OUT
= 20V)
100
70
60
90
80
MAX1677-05
LOAD CURRENT (mA)
EFFICIENCY (%)
CIRCUIT OF FIGURE 2
A: V
IN
= 3.6V
B: V
IN
= 2.4V
C: V
IN
= 1.2V
A
B
C
1.2450
1.2475
1.2525
1.2500
1.2550
0
20
40
60
80
100
REFERENCE VOLTAGE
vs. REFERENCE CURRENT
MAX1677-06
REFERENCE CURRENT (
µA)
REFERENCE VOLTAGE (V)
Typical Operating Characteristics
(Circuits of Figures 2 and 3, T
A
= +25°C, unless otherwise noted.)
0
100
50
250
200
150
400
350
300
450
0
1.0
0.5
1.5
2.0
2.5
3.0
LOAD CURRENT
vs. STARTUP VOLTAGE
MAX1677-07
START-UP VOLTAGE (V)
LOAD CURRENT (mA)
PWM
PFM
V
OUT
= 3.3V
TESTED WITH
RESISTIVE LOAD
0
0.06
0.04
0.02
0.10
0.08
0.18
0.16
0.14
0.12
0.20
0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
NO-LOAD SUPPLY CURRENT vs.
INPUT VOLTAGE (LCD OFF)
MAX1677-08
INPUT VOTAGE (V)
SUPPLY CURRENT (mA)
V
OUT
= 3.3V
PFM MODE
LCD OFF
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1.1
0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
NO-LOAD SUPPLY CURRENT vs.
INPUT VOLTAGE (LCD ON)
MAX1677-09
INPUT VOLTAGE (V)
SUPPLY CURRENT (mA)
V
OUT
= 3.3V
PFM MODE
V
LCD
= -20V