STW4141 STMicroelectronics, STW4141 Datasheet - Page 15

• Manufacturer Part Number: STW4141
• Description: Single Coil Dual Output Step Down Dc/dc Converter For Digital Base Band And Multimedia Processor Supply
• Manufacturer: STMicroelectronics

STw4141
2.11
Figure 9.
200
I
OUT1
180
160
(mA)
140
Efficiency vs I
120
100
100
100
Efficiency in PWM mode @ V
90
80
70
60
50
40
30
20
10
90
80
70
60
50
40
30
20
10
0
0
Efficiency vs I
80
1
1
Efficiency in PWM
The efficiency of a switching regulator is equal to the total output power divided by the input.
STw4141 has high efficiency up to 92% (for the 2 outputs). Efficiency curve is flat over the
output current range.
Switching regulator efficiency in PWM mode
60
V
V
V
40
V
V
V
IN
OUT1
OUT2
IN
OUT1
OUT2
20
= 2.7V
= 2.7V
= 1.8V
= 1.2V
= 1.8V
= 1.2V
1
OUT1
OUT2
@I
10
10
OUT2
@I
I
I
OUT2
OUT1
OUT1
PWM mode, TA=25°C
(mA)
(mA)
I
OUT2
, PWM mode, T
IN
(mA)
100
100
=2.7V, T
0
10
20
30
40
50
I
I
60
I
OUT1
OUT1
70
I
I
I
OUT1
80
OUT2
OUT2
OUT2
90
100
A
= 100 mA
= 200 mA
Efficiency (%)
= 0 mA
= 200 mA
= 400 mA
= 0 mA
= 25°C
90-100
80-90
70-80
60-70
50-60
40-50
30-40
20-30
10-20
0-10
A
=25°C
1000
1000
200
I
OUT1
180
160
(mA)
140
Efficiency vs I
120
Efficiency vs I
100
100
100
Efficiency in PWM mode @ V
90
80
70
60
50
40
30
20
10
90
80
70
60
50
40
30
20
10
0
0
80
1
1
60
V
V
V
V
V
V
40
IN
OUT1
OUT2
IN
OUT1
OUT2
= 3.6V
20
= 3.6V
= 1.8V
= 1.2V
= 1.8V
= 1.2V
1
OUT1
OUT2
@I
10
10
@I
OUT2
OUT1
I
OUT2
Electrical characteristics
I
OUT1
PWM mode, TA=25°C
(mA)
(mA)
, PWM mode, T
I
OUT2
IN
100
(mA)
100
=3.6V, T
0
10
30
20
I
I
40
I
OUT1
OUT1
50
OUT1
60
70
80
I
I
I
90
100
OUT2
OUT2
OUT2
A
= 100 mA
= 200 mA
= 0 mA
A
= 25°C
Efficiency (%)
= 0 mA
= 200 mA
= 400 mA
=25°C
90-100
80-90
70-80
60-70
50-60
40-50
30-40
20-30
10-20
0-10
1000
1000
15/30