Hello,
Regarding the MMWCAS-RF-EVM, in the user-guide we can check the stack up used for the PCB design (page 41).
https://www.ti.com/lit/ug/swru553a/swru553a.pdf?&ts=1589469204411
I have a question regarding the RO4450F used between layers 2 and 3. In the user guide as well as in the PCB layout, this substrate is defined as having a thickness of 5 mils and a Dk of 4.2. However, Rogers Corp. documentation specifies this substrate is available on multiples of 4 mils and its Dk is way lower than 4.2 (near 3.52).
Am I missing something or is there an error in the substrate used?
Thank you
