RTOS/CC2640R2F: RF-PHY Test failed

- You state the results failed, please report the results
- Which SDK do you use?
- Which board are you using, if a custom board, we can do a quick schematic review to see if we can see something that could explain the poor sensitivity.

Hi,

we are using SDK 2.30.0.28

We found out so fare that LF RCOSC was not configured in the test firmware, could this the reason for the attached test results?

Thanks for your help

Best Regards,

Marco

TestResults.zip

Hi Marco,

The LF clock is not important for PHY testing, so not properly configuring the RCOSC-LF should not matter.

The test results you have posted indicates some kind of HW design issue. Can you post a picture of the layout for the CC2640R2F part?

Potential root causes for what you are seeing could be:
- Poor DCDC regulator layout (try running the PHY test with DCDC disabled in CCFG).
- Noise coupling from external switching regulators (try powering the CC2640R2F directly from a lab supply).
- Poor layout of the RF circuitry with poor ground connections.

Regards,
Fredrik

HI Fredrik,

thanks for responding.

for DCDC disabled you mean this right?
#define SET_CCFG_MODE_CONF_DCDC_RECHARGE 0x1 // Do not use the DC/DC during recharge in powerdown
#define SET_CCFG_MODE_CONF_DCDC_ACTIVE 0x1 // Do not use the DC/DC during active mode

What concrete you want to see of the layout? When you give me your E-Mail via Direct Message I can send you the Eagle Files.

Best Regards,
Marco

Please send me a friend request and then it will be possible to send me the schematic and layout directly. The layout should be gerber files.

HI

- The value on C507
It is 4u7F as this part is allready used on the board
- Why C504/ C505
Because the balun has no internal dc block specified
- The balun choice, see chapter 7 in www.ti.com/.../swra640.pdf
When we develop the layout this was the best fit for cc2640r2f
- What will the voltage on DIO3 etc when you supply the LEDs with VBAT?
The resistor array has been removed in order to connect the serial ports for testing over launchpad. DIO3 is limited to 1.8V


The error is related to modulation and demodulation, the RF frontend passed the tests on receive and transmit side.
The modulaiton even passed the requiered bandwith on a pattern 00001111 but failed on 10101010 see page 22 on the RF-PHY.TS.5.0.3.pdf send via Direct Message

Regards,
Marco