Typical operating characteristics (continued) – Rainbow Electronics MAX8668 User Manual
Page 5
MAX8667/MAX8668
1.5MHz Dual Step-Down DC-DC Converters
with Dual LDOs and Individual Enables
_______________________________________________________________________________________
5
0
40
20
80
60
100
120
0
1
2
3
4
5
NO-LOAD SUPPLY CURRENT vs. SUPPLY
VOLTAGE OUT3 AND OUT4 ONLY
MAX8667/88 toc10
SUPPLY VOLTAGE (V)
I
IN34
(μ
A)
V
IN12
= 5.5V
V
IN34
VOLTAGE
RISING
V
IN34
VOLTAGE
FALLING
2.50
2.65
2.60
2.55
2.70
2.75
2.80
2.85
2.90
2.95
3.00
2.5
3.5
3.0
4.0
4.5
5.0
5.5
OUT3 OUTPUT VOLTAGE
vs. INPUT VOLTAGE (300mA LOAD)
MAX8667/88 toc11
INPUT VOLTAGE (V)
OUTPUT VOLTAGE (V)
0
10
20
30
40
50
60
70
80
0
100
200
300
OUT3 DROPOUT VOLTAGE
vs. LOAD CURRENT
MAX8667/88 toc12
LOAD CURRENT (mA)
DROPOUT VOLTAGE (mV)
0
300
200
100
400
500
600
700
800
900
1000
2.5
3.5
3.0
4.0
4.5
5.0
5.5
SUPPLY CURRENT vs. SUPPLY VOLTAGE
MAX8667/88 toc13
SUPPLY VOLTAGE (V)
SUPPLY CURRENT (mA)
IN12 = IN34
2.4
Ω LOAD ON OUT1
3.6
Ω LOAD ON OUT2
NO LOAD ON OUT3
NO LOAD ON OUT4
40
μs/div
ENABLE WAVEFORMS
EN1/EN2/
EN3/EN4
V
OUT1
V
OUT2
5V/div
2V/div
2V/div
2V/div
2V/div
2A/div
2A/div
2A/div
MAX8667/88 toc14
V
OUT4
I
L1
V
OUT3
I
L2
I
IN12
+ I
IN34
40
μs/div
SHUTDOWN WAVEFORMS
EN1/EN2/
EN3/EN4
V
OUT1
V
OUT2
5V/div
1V/div
1V/div
1V/div
1V/div
MAX8667/88 toc15
V
OUT4
V
OUT3
Typical Operating Characteristics (continued)
(V
IN12
= V
IN34
= 3.6V, circuit of Figure 4, V
OUT1
= 1.2V, V
OUT2
= 1.8V, V
OUT3
= 2.8V, V
OUT4
= 2.8V, T
A
= +25°C, unless otherwise noted.)
10
μs/div
OUT1 LOAD TRANSIENT
V
OUT1
I
OUT1
100mV/div
(AC-COUPLED)
200mA/div
200mA/div
MAX8667/88 toc16
I
L1
300mA
10mA
10mA