CC2545 spurious emission

The 64 MHz spur is described in the datasheet "Designs with antenna connectors that require conducted ETSI compliance at 64 MHz should insert an LC resonator in front of the antenna connector. Use a 1.6-nH inductor in parallel with a 1.8-pF capacitor. Connect both from the signal trace to a good RF ground." To help you more you most post your schematic and layout to check the crystal routing.

in cc2545 datasheet,we didn't find "Designs with antenna connectors that require conducted ETSI compliance at 64 MHz should insert an LC resonator in front of the antenna connector. Use a 1.6-nH inductor in parallel with a 1.8-pF capacitor. Connect both from the signal trace to a good RF ground"，can you send me this document?

sorry, the wording in the CC2545 datasheet is
"Use a simple LC filter (1.6nH and 1.8pF in parallel to ground) to pass ETSI conducted requirements below 1GHz in restricted bands. For radiated measurements low antenna gain for these frequencies (depending on antenna design) can achieve the same attenuation of these low frequency components (see EM reference design)." p 6

hi chs

pls show a circuit picture,tks

I do not have one, but note that this filter should not be needed if using an antenna like in your design (only needed for conducted measurements). If you want to test, the filter should be placed after the last filter comp (L303 in our ref design) and before the antenna matching (R256/C257 in our ref design). Here you should add two components in parallel to ground, one inductor and one capacitor. It is not easy to see from your attaced pictures, but the grounding does not look optimal, especially for the crystal. Components with ground connection should not share vias to gorund but have separate vias.

Hi CHS

so,the circuit is like this,is it?

correct.