sc250wltrt Semtech Corporation, sc250wltrt Datasheet - Page 10

• Manufacturer Part Number: sc250wltrt
• Description: Sc250 Step-down Dc-dc Converter With Bias Ldo For Rf Power Amplifiers
• Manufacturer: Semtech Corporation

PCB Layout Considerations
Poor layout can degrade the performance of the DC-
DC converter and can be a contributory factor in EMI
problems, ground bounce and resistive voltage losses.
Poor regulation and instability can result.
A few simple design rules can be implemented to ensure
good layout:
1.
2.
© 2006 Semtech Corp.
POWER MANAGEMENT
Applications Information (Cont.)
Place the inductor and fi lter capacitors as close to the
device as possible and use short wide traces between
the power components.
Route the output voltage feedback and V
from inductor and LX node to minimize noise and
magnetic interference.
PGND
V
VREF
VDAC
EN
GND
IN
C
IN
C
REF
DAC
LX
1
path away
L
SC250
OUT
10
3.
4.
Maximize ground metal on component side to improve
the return connection and thermal dissipation.
Separation between the LX node and GND should be
maintained to avoid coupling of switching noise to the
ground plane.
To further reduce noise interference on sensitive
circuit nodes, use a ground plane with several vias
connecting to the component side ground.
C
OUT
V
OUT
PRELIMINARY
www.semtech.com
SC250