SNVS129F May 2004 – June 2016 LM2675
Layout is very important in switching regulator designs. Rapidly switching currents associated with wiring inductance can generate voltage transients which can cause problems. For minimal inductance and ground loops, the wires indicated by heavy lines (in Figure 19 and Figure 24) must be wide printed circuit traces and must be kept as short as possible. For best results, external components must be placed as close to the switcher IC as possible using ground plane construction or single-point grounding.
If open-core inductors are used, take special care as to the location and positioning of this type of inductor. Allowing the inductor flux to intersect sensitive feedback, IC ground path, and COUT wiring can cause problems.
When using the adjustable version, take special care as to the location of the feedback resistors and the associated wiring. Physically locate both resistors near the IC, and route the wiring away from the inductor, especially an open-core type of inductor.
The LM2675 is offered in the 16-pin WSON surface-mount package to allow for increased power dissipation compared to the SOIC and PDIP.
The die attach pad (DAP) can and must be connected to PCB Ground plane or island. For CAD and assembly guidelines see AN-1187 Leadless Leadframe Package (LLP).