yes，we measure it. The spurs originate from CC1125. The PA just amplify the spurs.Can you  measure your demo board whether it has the spurs?

Part Number: CC1125

Tool/software: TI C/C++ Compiler

hi TER,

 AS you said, you did measure @460 MHz but with a 32 MHz xtal (I could not find any EMs with 40 MHz for this frequency band) and did not see any spurs.

BUT, I measure  the demo board with a 40 MHz Xtal, as the result showed (the spectrum Maxhold), some unwanted spurs found near the main signal 460Mhz. The Interval frequency is about 40MHz or 20MHz. Is your measurement test the same as mine?4452.CC1125 demoboard unwanted spurs 20190219.docx

Hi, TER，

This is my latest measurements.

I test the demo board with a 40 MHz Xtal, as the result showed (the spectrum Maxhold), some unwanted spurs found near the main signal 460Mhz. The Interval frequency is about 40MHz or 20MHz. Is your Spectrum Analyzer  setting(RBW, VBW, ATT and so on) the same as mine?  Can you sending your test result in your attachment?

4606.CC1125 demoboard unwanted spurs 20190219.docx

Hi,TER

       If I add an amplifier after CC1125，the RF output power will be 30 dBm, and the highest spurs above -30 dBm. According to CE certification, the spurs(sub 1 G) must not exceed -36 dBm. So can you have any way to low down the spurs@40 Mhz  offset?

hi，TER

Yes，I agree with you. I ask another question. CC1125 output has so many recomended LC components, which are matched circuit or LC BPF ? IF it is the LC BPF ,why its bandwith is so large?  It can't low down the low frequency spurs.

best wishes

 han

hi ,TER,

you said,you measured clock spurs in the -60 dBm range @40 MHz offset,can you have any methods( such as changing the configuration of CC1125  ) to low down the  clock spurs? Because  we want to output signal of  45dBm , and the  clock spurs  is about -25dBm, its so high.

using a CC1125 + a evaluation board with the PA I want to use, the resulting spurs(40MHz@offset) is about -22dBm. Is there  any  way to low the spurs?