AS1341
Datasheet - Application Information
9 Application Information
9.1 Adjusting Output Voltage
The AS1341 feedback input features dual-mode operation. Connect FB to GND for the 5.0V preset output voltage (see Figure 21 on page 8).
Adjust the output voltage by connecting a voltage-divider from the output to GND (see Figure 22).
Figure 22. Adjustable Output Voltage Circuit
V
IN
L1
R
4.5V to 20V
1.25V to VIN
5
IN
4
LX
D1
+
7
CIN
COUT
PULL
SHDNN
6
3
AS1341
R
R
1
2
POK
1
ILIMIT
FB
2
8
GND
OUT
Indicates High-Power Trace
Select a value for R2 between 10k and 1MΩ.
Calculate R1 as:
VOUT
-------------
R1 = R2
– 1
(EQ 2)
VFB
Where:
V
V
FB = 1.25V.
OUT may range from 1.25V to VIN
.
9.2 Negative Output Voltage
V
IN may range from 4.5V to (20V-VOUT). Therefore the maximum negative output voltage is -15V.
Figure 23. Adjustable Negative Output Voltage Circuit
V
IN
L1
4.5V to (20V-VOUT)
5
IN
4
LX
D1
3
7
R
R
1
2
POK
SHDNN
6
AS1341
1
+
C
OUT
C
IN
FB
ILIMIT
8
2
OUT
GND
V
OUT = -1.25V to -15V
Indicates High-Power Trace
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Revision 1.09
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