ltm8022 Linear Technology Corporation, ltm8022 Datasheet - Page 12

• Manufacturer Part Number: ltm8022
• Description: 1a, 36v Dc/dc ?module
• Manufacturer: Linear Technology Corporation

APPLICATIONS INFORMATION
PCB Layout
Most of the headaches associated with PCB layout
have been alleviated or even eliminated by the high
level of integration of the LTM8022. The LTM8022 is
nevertheless a switching power supply, and care must be
taken to minimize EMI and ensure proper operation. Even
with the high level of integration, you may fail to achieve
specifi ed operation with a haphazard or poor layout. See
Figure 4 for a suggested layout.
Ensure that the grounding and heatsinking are acceptable.
A few rules to keep in mind are:
1. Place the R
2. Place the C
LTM8022
12
tive pins as possible.
and GND connection of the LTM8022.
ADJ
IN
capacitor as close as possible to the V
and R
T
resistors as close to their respec-
GND PLANE
Figure 4. Layout Showing Suggested External
Components, GND Plane and Thermal Vias
V
OUT
PLANE
C
OUT
IN
3. Place the C
4. Place the C
5. Connect all of the GND connections to as large a copper
6. Use vias to connect the GND copper area to the boards
SHARE
AUX
V
ground current fl ow directly adjacent or underneath the
LTM8022.
pour or plane area as possible on the top layer. Avoid
breaking the ground connection between the external
components and the LTM8022.
internal ground plane. Liberally distribute these GND vias
to provide both a good ground connection and thermal
path to the internal planes of the printed circuit board.
C
R
IN
T
OUT
BIAS
LTM8022
and GND connection of the LTM8022.
V
IN
PLANE
R
ADJ
OUT
IN
SYNC
PG
RUN/SS
and C
capacitor as close as possible to the
OUT
capacitors such that their
8022f