LTC3725 Datasheet, PDF (16/20 Pages) Linear Technology – Single-Switch Forward Controller and Gate Driver

LTC3725
APPLICATIO S I FOR ATIO
Effective grounding can be achieved by considering the
return current paths from the sense resistor to each
respective bypass capacitor. Don’t be tempted to run small
traces to separate the grounds. A power ground plane is
important as always in high power converters, but care
must be taken to keep high current paths away from the
GND reference. An effective approach is to use a 2-layer
ground plane, reserving an entire layer for GND and an
entire layer for PGND. The UVLO and frequency set
resistors can then be directly connected to the GND plane.
V_IN
V_CC
V_IN
LTC3725
UVLO
FS/IN^–
V_CC
GATE
GND
PGND
SIGNAL GROUND PLANE
POWER GROUND PLANE
3725 F05
Figure 5. High Current Transient Return Paths
3725f
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