
Dual, 4A/2A, 4MHz, Step-Down DC-DC
Regulator with Dual LDO Controllers
Typical Operating Characteristics
(V AVIN = V DVDD1 = V DVDD2 = V PVIN1 = V PVIN2 = 5V, V OUT1 = 3.3V, V OUT2 = 1.5V, V PGND_ = 0V, R T = 16.5k ? . T A = +25°C, unless
otherwise noted.)
100
90
80
CHANNEL 1 EFFICIENCY
vs. LOAD CURRENT
100
90
80
CHANNEL 1 EFFICIENCY
vs. LOAD CURRENT
100
90
80
CHANNEL 2 EFFICIENCY
vs. LOAD CURRENT
70
60
V PVIN1 = 5V
V PVIN1 = 3.3V
70
60
V OUT1 = 1.8V
V OUT1 = 1.0V
70
60
P VIN2 = 5V
P VIN2 = 3.3V
50
50
50
40
30
40
30
V OUT1 = 3.3V
40
30
20
10
V OUT1 = 1.8V
f SW = 2MHz
EN2 = 0V
20
10
V PVIN1 = 5V
f SW = 2MHz
EN2 = 0V
20
10
V OUT2 = 1.5V
f SW = 2MHz
EN1 = 0V
0
0
0
100
1000
5000
100
1000
5000
100
1000
3000
100
90
80
LOAD CURRENT (mA)
CHANNEL 2 EFFICIENCY
vs. LOAD CURRENT
3.320
3.318
3.316
LOAD CURRENT (mA)
CHANNEL 1
LOAD REGULATION
1.5070
1.5065
1.5060
LOAD CURRENT (mA)
CHANNEL 2
LOAD REGULATION
70
V OUT2 = 2.5V
3.314
1.5055
60
50
40
30
20
V OUT2 = 1.0V
V OUT2 = 1.5V
V PVIN2 = 5V
3.312
3.310
3.308
3.306
3.304
1.5050
1.5045
1.5040
1.5035
1.5030
V PVIN2 = 5V
V PVIN2 = 3.3V
10
0
f SW = 2MHz
EN1 = 0V
3.302
3.300
V PVIN1 = 5V
f SW = 2MHz
1.5025
1.5020
f SW = 2MHz
100
1000
3000
0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
0
0.25 0.50 0.75 1.00 1.25 1.50 1.75 2.00
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
LOAD CURRENT (mA)
SWITCHING FREQUENCY
vs. RT RESISTANCE
LOAD CURRENT (A)
0.5
0.4
0.3
0.2
0.1
0
-0.1
-0.2
-0.3
LOAD CURRENT (A)
SWITCHING FREQUENCY
vs. TEMPERATURE
0.5
0
-0.4
-0.5
f SW = 2MHz
0
5
10
15
20
25
30
35
-40 -25 -10 5 20 35 50 65 80 95 110 125
RT RESISTANCE (k ? )
TEMPERATURE ( ° C)
_______________________________________________________________________________________
5