JAJSPC8C December 2022 – February 2024 TPSM33615 , TPSM33625
PRODUCTION DATA
As previously mentioned, TI recommends using one of the middle layers as a solid ground plane. A ground plane provides shielding for sensitive circuits and traces as well as a quiet reference potential for the control circuitry. Connect the GND pin to the ground planes using vias next to the bypass capacitors. The GND trace, as well as the VIN and SW traces, must be constrained to one side of the ground planes. The other side of the ground plane contains much less noise; use for sensitive routes.
TI recommends providing adequate device
heat-sinking by having enough copper near the GND
pin. See
Figure 8-23 for example layout. Use as much copper as
possible, for system ground plane, on the top and
bottom layers for the best heat dissipation. Use a
four-layer board with the copper thickness for the
four layers, starting from the top as: 2 oz / 1 oz
/ 1 oz / 2 oz. A four-layer board with enough
copper thickness, and proper layout, provides low
current conduction impedance, proper shielding and
lower thermal resistance.