3 Board Layout
This section provides description of the TPS54225EVM-538, board layout, and layer illustrations.
3.1 Layout
The board layout for the TPS54225EVM-538 and is shown in
contains the main power traces for VIN, VO and ground. Also on the top layer are connections for the pins of
the TPS54225 and a large area filled with ground. Many of the signal traces are also located on the top side.
The input decoupling capacitor are located as close to the IC as possible. The input and output connectors, test
points and most of the components are located on the top side. R3, the 0-Ω resistor that connects VIN to VCC
and R4, the power good pull up, are located on the back side. Analog ground and power ground are connected
at a single point on the top layer near pin 5 of the TPS54225. The internal layer 1 is a split plane containing
analog and power grounds. The internal layer 2 is primarily power ground. There are also a fill area of VIN and a
trace routing VCC to the enable control jumper JP1. The bottom layer is primarily analog ground. There are also
traces to connect VIN to VCC through R3, traces for the power good signal and the feedback trace from VOUT
to the voltage setpoint divider network.
Figure 3-1. Top Assembly
Board Layout
SLVU337A – NOVEMBER 2009 – REVISED OCTOBER 2021
TPS54225 Step-Down Converter Evaluation Module User's Guide
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