AS1324 AMSCO [austriamicrosystems AG], AS1324 Datasheet - Page 16

• Manufacturer Part Number: AS1324
• Description: 1.5MHz, 600mA, DC/DC Step-Down Regulator
• Manufacturer: AMSCO [austriamicrosystems AG]

AS1324
Data Sheet - A p p l i c a t i o n I n f o r m a t i o n
For best overall efficiency use an inductor with a rating of 720mA or greater and less than 0.2 Ω series resistance. C
will require an RMS current rating of at least 0.3A
0.25 Ω . In most cases, a ceramic capacitor will satisfy this requirement.
For the feedback resistors, select the value for R
Layout Considerations
The AS1324 requires proper layout and design techniques for optimum performance.
Figure 29. AS1324 Basic PCB Layout
Figure 30. AS1324 Basic Diagram
www.austriamicrosystems.com
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The power traces (GND, SW, and V
Pin V
replacement for R
the regulator.
The resistive divider (R
The positive plate of C
the internal power MOSFETs.
Switching node SW should be kept far away from the sensitive V
The negative plates of C
recommended.
V
FB
OUT
(AS1324 only) should be connected directly to the feedback resistors (R
1
and R
IN
V
1
OUT
/R
IN
should be connected as close to V
2
2
and C
should be avoided to minimize the output voltage ripple and to maintain the stability of
) must be connected between the positive plate of C
L
1
OUT
C
OUT
IN
L
should be kept as close to each other as is practical. A starpoint to Ground is
SW
R
) should be kept as short, direct, and wide as is practical.
1
2
C
= (V
GND
OUT
SW
EN
1
2
3
1
2
3
1
OUT
AS1324
≅
= 375k Ω . R
GND
Via to V
I
LOAD(MAX)
Revision 1.03
/0.6 - 1)375k = 1000k Ω
AS1324
C
IN
5
4
IN
2
/2, whereas C
C
can then be calculated from
IN
C
R
R
IN
FWD
as is practical since C
1
2
5
VFB
4
VIN
FB
node.
R
OUT
2
V
IN
C
will require an ESR of less than
FWD
Via to GND
Via to V
OUT
1
and R
IN
and ground.
OUT
provides the AC current to
(EQ 7)
2
R
). A potentiometer as
1
V
High Current Path
IN
to be:
16 - 20
IN