as1331 austriamicrosystems, as1331 Datasheet - Page 12

• Manufacturer Part Number: as1331
• Description: 300ma Buck-boost Synchronous Dc/dc Converters
• Manufacturer: austriamicrosystems

AS1331
Data Sheet - D e t a i l e d D e s c r i p t i o n
Output Voltage Selection
The AS1331 is available in two versions
fixed output voltage
to 3.3V by connecting a voltage divider between the pins
Figure 24. LiIon to Adjustable Output Voltage
The output voltage can be adjusted by selecting different values for R
Calculate V
Where:
V
Figure 25. LiIon to 3.3V with POK - Fixed Output Voltage
www.austriamicrosystems.com
FB
= 1.25V, V
LiIon
LiIon
OUT
OUT
by:
= 2.5V to 3.3V;
(see Figure 25)
10µF
C
10µF
1
C
1
and the other version can operate with user-adjustable output voltages from 2.5V
On
Off
On
Off
(see Ordering Information on page
VIN
LBI
EN
VIN
LBI
EN
5
7
6
5
7
6
V
OUT
3
4
3
4
AS1331-AD
Revision 1.02
PGND
SW1
=
PGND
AS1331-
SW1
6.8µH
V
6.8µH
3.3V
VOUT
L1
FB
L1
×
⎛
⎝
9
2
1
9
2
and FB
+
GND
SW2
GND
R
----- -
R
SW2
1
2
⎞
⎠
1
and R
8
LBO
1
VOUT
10
FB
8
LBO
1
VOUT
10
FB
(see Figure
15). One version can only operate at one
2
.
R
R
R
R
2
1
3
3
24).
22µF
C
2
22µF
C
2
300mA
V
3.3V
2.5V to 3.3V
OUT
V
OUT
(EQ 2)
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