Hello,
The layout example provided in Figure 25 of the datasheet shows that the mode and feedback resistors are placed outside of the ground pour that's on the component layer. This ground pour connects the input and output cap grounds. In a multi-layer board, where there is an adjacent ground plane (say 5 mils under the component layer), would the copper pour be necessary, and if so, would bringing in the mode and feedback resistor inside the copper pour be OK? Placing these resistors between the device and the copper pour will provide a few benefits: 1) Eliminate quite a few of the vias that are associated with them in the illustrated example, 2) shorten the feedback trace, and 3) allow the grounds of these resistors to tie directly to AGND. Are there any disadvantages to this approach, say in terms of EMI performance?
Thanks,
Narek