CC1310: External PA integration in single ended mode for 915Mhz

See www.ti.com/.../swra517.pdf

This solution can relatively easy be converted to a single ended design.

Hi TER,

Thanks for the prompt reply. I want to integrate RFFM6904 with CC1310 operating on 915MHZ. I will not be able to use CC1190 as I need higher POUT. 

RFFM6904 has different Tx and Rx path so want to know how to interconnect this without converting CC1310 RF out to single-ended.

Thanks.

It looks like the FEM you intend to use has single ended in/ out both for the PA and LNA. 

Either you have to combine the PA in and LNA out in a 50 ohm point as done on the CC1310-CC1190 design or you can take a look at  for how to make a single ended design on CC1310 with one RX and one TX path that can be connected to the FEM. 

Hi TER,
Thanks for the reference. Will this configuration also work for 923-925 band that it is supposed to be designed for???

Most likely. It could be that you have to adjust the match/ filter slightly since the wanted output power is high. It depends also on the amount of filtering in the FEM if extra attenuation is needed.

Hi TER,

Thanks for your prompt replies. Can you pls reveiw the attached schematics. this is for 915Mhz operation.

Hi TER,

Could you help to review the attached schematics.

Thanks.

I was out of office last week, sorry about the delay

RX path: Do you need a filter here or just a simple 50 ohm match?
TX path: Without any filtering the harmonics in on the FEM will be high. Is this OK?

Power: Check your VDDR power. For me it looks like everything is powered on 3v3_RF.

Hi TER,

Thanks for your response.

RX path: Do you need a filter here or just a simple 50 ohm match? 

50Ohm match @ 923-925 MHz is sufficient.

TX path: Without any filtering the harmonics in on the FEM will be high. Is this OK? 

900MHz band SAW will be used for harmonic suppression.

Power: Check your VDDR power. For me it looks like everything is powered on 3v3_RF.

Thanks for the highlight. Net corrected

Hi TER,

Can you suggest a discrete filter for such high power?

The power between the SoC and the FEM will be a few dBm meaning that you don't have to take any special consideration power wise when designing the filter.

My point was on the output of FEM.