CC1314R10: CC1314 runs at 1250Mhz, and the TX power is too low.

Hi,

• Please share more information about your measurement setup.
• Are you using custom hardware and/or have you performed the same measurement on TI hardware?
• What version of SmartRF Studio 7 are you using (we always recommend the latest)?
• What Target Configuration did you select for the CC1314R10 in SmartRF Studio?

Regards,

Zack

Hi ZC.

1. Our engineers downloaded the latest smart RF studio version 2.31.0, but we still have this problem.

2. Our RF Design is Based on LP_CC1314R10_RGZ, The chip we use is also the RGZ version.(At the same time, I also set the target configuration to LP_EM_CC1314R10 and still have the same problem.)

3. We used a self-developed module to perform 1250Mhz RF matching. To analyze this problem, we first used the CC1312 chip for measurement. After the measurement, we changed the chip to CC1314, and then measured again. The above tests were all performed at the same time. on a PCB board.

Hi,

Please expect a reply by Wednesday next week for this as I need to see if this is reproducible in the lab. It will not be 1-1 as we do not have a reference design, but I can see if I can reproduce the low output power.

However, this looks like it could be a soldering issue - please can you double check this?

Regards,

Zack

Hi ZC.

We tried several modules, and when CC1314 had no TX power, we switched to CC1312, and the power returned to normal.

In addition, today we asked our engineers to directly wire from the CC1314 chip's RF port to the spectrum. When it is wired from the chip pin, its transmit power is still about -13dBm.

Hi ZC.

good day.

do you have any status?

Hi,

Apologies but I've had limited lab access - this hasn't been forgotten. I will provide feedback for this when I am able to test it (it may be mid-next week, to set expectations).  

Regards,

Zack

A follow-up - please can you share your BOM for 1250 MHz operation? I have sent a friend request so that you do not need to do this publicly. Please also indicate if it uses 0201 or 0402 components so that I can use the correct TI LaunchPad for testing.

Otherwise just mounting a CC1314R10 RGZ device onto a CC1312Rx board will not produce any output power (as the baluns are designed for 868/915 MHz operation on those designs).

Regards,

Zack

Hi ZC,
I have sent you the matching circuit of the balun.
Thank you for your assistance.

Hi ZC,

When you are experimenting,
I think you can directly measure the tx power at the pin outlets of RFP and RFN.
Our engineers use CC1312 and CC1314 to directly measure the tx power at the RFP and RFN, which are -13dbm and +10dbm respectively.

I decided to investigate this a little more. There is obviously something in the radio
that prevents the chip from performing.

I have used SmartRf Studio 7, with a LAUNCHXL-CC1314 the EWB, marked CC1312R1 delivered

from TI.

My findings are that there is an abrupt limit at 931 Mhz, where the output drops from +13 dBm
to - 13 dBm

With an Advantest SA I have plotted frequencies from 800 to 1300 Mhz, and at all frequencies
from 800 - 930.99 Mhz the output is +13 dBm with some small variation.

At 931 Mhz, output drops to -12 or so, and in the range 1200 Mhz and up the output drops
several dB more.

This indicates some "limit" set above 931 Mhz, and these measurements are made with an
unmodified filter. The "several" dB drop above 1200 can be explained with the low pass
filter used to match the antenna, or balun mismatch.

Comments to this is much welcome, since we are working on a radio for these frequencies.

Gullik

Could this have something to do with the PA-table, and unsuitable values?

Why would this depend so abruptly on frequency?

G

Perfect, now we can proceed as planned with the project.

Gullik

Hi both,

I just want to confirm that you regard this issue as resolved, or do you still need additional lab results from TI's side to help with this issue?

Regards,
Zack

Hi ZC,

We have no other question for this issue.

Thx.