STW41412/T ST-Ericsson Inc, STW41412/T Datasheet - Page 21

• Manufacturer Part Number: STW41412/T
• Description: IC CONV DC/DC STPDN 16-TFBGA
• Manufacturer: ST-Ericsson Inc
• Type: Step-Down (Buck)r

Specifications of STW41412/T

• Internal Switch(s): Yes
• Synchronous Rectifier: Yes
• Number Of Outputs: 2
• Voltage - Output: 1.3V, 1.8V
• Current - Output: 200mA, 400mA
• Frequency - Switching: 900kHz
• Voltage - Input: 2.7 ~ 5.5 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 16-TFBGA
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Power - Output: -

Application information
4.2
4.3
20/30
Automatic PWM/PFM mode
This user mode is designed to allow STw4141 to switch automatically between PWM and
PFM modes. This feature improves the application efficiency because STw4141 enters in
PFM mode according to application processor current consumption.
Figure 12. Automatic PWM/PFM switch schematic example
User selected PWM/PFM mode
STw4141 PWM/PFM mode can also be controlled by the application processor. This feature
is accessible through MODE/SYNC pin state. It is useful to users who want to use STw4141
with the modem digital processor. Therefore, MODE/SYNC pin is connected to SLEEP
mobile phone signal.
Figure 13. PWM/PFM forced mode schematic example
V
V
V
V
IN
IN
IN
IN
=2.7V to 5.5V
=2.7V to 5.5V
=2.7V to 5.5V
=2.7V to 5.5V
C
C
10 µF
10 µF
6.3 V
6.3 V
C
C
10 µF
10 µF
6.3 V
6.3 V
IN
IN
IN
IN
MODE/SYNC
MODE/SYNC
MODE/SYNC
MODE/SYNC
PVDD
PVDD
VDD
VDD
EN
EN
AUTO
AUTO
VSEL
VSEL
PVDD
PVDD
VDD
VDD
EN
EN
AUTO
AUTO
VSEL
VSEL
B1
B1
D3
D3
D4
D4
C2
C2
C3
C3
C1
C1
B1
B1
D3
D3
D4
D4
C2
C2
C3
C3
C1
C1
A2
A2
A2
A2
A1
A1
A1
A1
VLX1
VLX1
VLX1
VLX1
PGND
PGND
PGND
PGND
STw4141
STw4141
STw4141
STw4141
L 4.7 µH
L 4.7 µH
L 4.7 µH
L 4.7 µH
C4
C4
C4
C4
GND
GND
GND
GND
B3
B3
B3
B3
A3
A3
A3
A3
T_MODE
T_MODE
T_MODE
T_MODE
VLX2
VLX2
VLX2
VLX2
D1
D1
D2
D2
D1
D1
D2
D2
A4
A4
B4
B4
B2
B2
A4
A4
B4
B4
B2
B2
VOUT1
VOUT1
FB1
FB1
VOUT2
VOUT2
FB2
FB2
VOUT1
VOUT1
FB1
FB1
VOUT2
VOUT2
FB2
FB2
STATE
STATE
STATE
STATE
C
C
22 µF
22 µF
6.3 V
6.3 V
C
C
22 µF
22 µF
6.3 V
6.3 V
C
C
22 µF
22 µF
6.3 V
6.3 V
C
C
22 µF
22 µF
6.3 V
6.3 V
OUT1
OUT1
OUT2
OUT2
OUT1
OUT1
OUT2
OUT2
C
C
100 nF
100 nF
C
C
100 nF
100 nF
C
C
100 nF
100 nF
C
C
100 nF
100 nF
1
1
2
2
1
1
2
2
MODE_INFO
MODE_INFO
SLEEP
SLEEP
MODE_INFO
MODE_INFO
PWR_EN
PWR_EN
SLEEP
SLEEP
APE I/O
APE I/O
APE CORE
APE CORE
APE I/O
APE I/O
APE CORE
APE CORE
APPLICATION
APPLICATION
APPLICATION
APPLICATION
PROCESSOR
PROCESSOR
PROCESSOR
PROCESSOR
GND
GND
GND
GND
STw4141