Customer is laying out CC2650MODA PCB. Please advise on layout questions below and confirm initial responses.
What are the vias next to pins 1 and 2?
[MA] They are RF test pads. TI recommends leaving a clearance in the top-side copper plane underneath the RF test pads.
When we use the dimensions above for the part to create the land pattern, we don’t get the land pattern in the data sheet. Seems like in some cases the nominal value is used and in other cases the max value is used. Do we ignore the physical dimension drawing to create a land pattern and just go with the land pattern suggested by TI in the datasheet? We have a concern about the 10.1 vs 10.2 and when I do the calculation using nominal, I also get 10.2 and if I use the max I get 10.1. The IPC calculator also uses nominal to get 10.2.
11.1 – 0.5-0.5 = 10.1, and 11.1 – 0.45 – 0.45 = 10.2.
The pads have rounded corners, is that necessary or are square pads OK?
[MA] Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate design recommendations.
Are the vias necessary in the 4 center ground pads?
Are there any other things we need to consider or know about before we create the land pattern?
Thanks,
Mark
