Datasheet
LT3740
16
3740fc
APPLICATIONS INFORMATION
PC Board Layout Considerations
As with all switching regulators, careful attention must be
paid to the PCB board layout and component placement.
■
Place the power components close together with
short and wide interconnecting trances. The power
components consist of the top and bottom MOSFETs,
the inductor, C
IN
and C
OUT
. One way to approach this
is to simply place them on the board fi rst.
■
Similar attention should be paid to the power components
that make up the boost converter. They should also be
placed close together with short and wide traces.
■
Always use a ground plane under the switching regulator
to minimize interplane coupling.
■
Minimize the parasitic inductance in the loop of
C
IN
, MOSFETs and D1 which carries large switching
current.
■
Use compact plane for switch node (SW) to improve
cooling of the MOSFETs and to keep EMI low.
■
Use planes for V
IN
and V
OUT
to maintain good voltage
fi ltering and to keep power losses low. Unused areas
can be fi lled with copper and connect to any DC node
(V
IN
, V
OUT
, GND)
■
Place C
B
close to BIAS pin and input capacitor.
■
Keep the high dv/dt nodes (SW, TG, BG, SWB) away
from sensitive small signal nodes.