Rainbow Electronics MAX669 - Manual (Page 5)

MAX668/MAX669
1.8V to 28V Input, PWM Step-Up
Controllers in µMAX
_______________________________________________________________________________________ 5
50
60
65
70
75
80
85
90
95
1 10 100 1000 10,000
EFFICIENCY vs. LOAD CURRENT
(V OUT = 5V)
MAX668 toc01
LOAD CURRENT (mA)
EFFICIENCY (%)
55
V IN = 3.3V
V IN = 3.6V
V IN = 2V
V IN = 2.7V
BOOTSTRAPPED
FIGURE 3
R4 = 200k
Ω
70
1 10,000 1000 10 100
MAX668 EFFICIENCY vs.
LOAD CURRENT (V OUT = 12V)
85
75
95
80
90 MAX668 toc02
LOAD CURRENT (mA)
EFFICIENCY (%)
V IN = 5V
NON-BOOTSTRAPPED
FIGURE 4
R4 = 200k
Ω
MAX668 EFFICIENCY vs.
LOAD CURRENT (V OUT = 24V)
MAX668 toc03
LOAD CURRENT (mA)
EFFICIENCY (%)
70
1 10,000 1000 10 100
85
75
95
80
90
V IN = 8V
V IN = 5V
V IN = 12V
NON-BOOTSTRAPPED
FIGURE 4
R4 = 200k
Ω
0
1.5
1.0
0.5
2.0
2.5
3.0
0 400 300 100 200 500 600 700 800 900 1000
MAX669 MINIMUM START-UP VOLTAGE
vs. LOAD CURRENT
MAX668 toc04
LOAD CURRENT (mA)
MINIMUM START-UP VOLTAGE (V)
V OUT = 5V
V OUT = 12V
BOOTSTRAPPED
FIGURE 2
0
0.5
1.5
2.0
2.5
3.0
3.5
0 10 5 15 20 25 30
SHUTDOWN CURRENT vs.
SUPPLY VOLTAGE
MAX668 toc07
SUPPLY VOLTAGE (V)
SHUTDOWN CURRENT (
µ
A)
1.0
CURRENT INTO V CC PIN
MAX668
MAX669
0
400
200
800
600
1000
1200
0 10 15 5 20 25 30
SUPPLY CURRENT vs.
SUPPLY VOLTAGE
MAX668 toc05
SUPPLY VOLTAGE (V)
SUPPLY CURRENT (
µ
A)
MAX669
MAX668
CURRENT INTO V CC PIN
R OSC = 500k Ω
0
500
1000
2000
2500
3000
3500
4000
0 4 2 6 8 10 12
NO-LOAD SUPPLY CURRENT vs.
SUPPLY VOLTAGE
MAX668 toc06
SUPPLY VOLTAGE (V)
NO-LOAD SUPPLY CURRENT (
µ A)
1500
V OUT = 12V
BOOTSTRAPPED
FIGURE 2
R4 = 200k
Ω
150
190
210
170
250
230
270
290
-40 -20 0 20 40 60 80 100
SUPPLY CURRENT vs.
TEMPERATURE
MAX668 toc08
TEMPERATURE ( ° C)
SUPPLY CURRENT (
µ
A)
R OSC = 100k Ω
R OSC = 200k Ω
R OSC = 500k Ω
0.1 1 10 20
LDO DROPOUT VOLTAGE vs.
LDO CURRENT
MAX668 toc09
LDO CURRENT (mA)
LDO DROPOUT VOLTAGE (mV)
300
0
50
100
150
200
250
V IN = 3V
V IN = 4.5V
Typical Operating Characteristics
(Circuits of Figures 2, 3, 4, and 5; T A = +25°C; unless otherwise noted.)