CC1200 layout question

The stackup is in the readme file in www.ti.com/.../swrr122

I assume that you mean not 50 ohm when you write "unmatching impedance"? The traces is much shorter than 1/10 wavelength and will therefore not behave like transmission lines.

Hi TER,

Thx for your reply.

It seems that all other traces does looks like they are match to 50 ohm and they are short too.

Bumping :-)

Thx

My first answer covered the issue hence no reply to your post.

For 433 MHz, a trace has to be fairly long to act like an transmission line. Hence NO traces in the reference design is 50 ohm. The PA output path is routed with slightly thicker traces due to IR drop, the line connected to pin 18 looks to me that is the same width as all other lines, eq a width slightly less than the solder pad for easy routing.