Hello, I am developing a device using stm32wl and I have a few questions.

[Andr_White]

The power supply diagram shows the vssa pin of the chip, but it is not specified in the Pinout. It is also not clear the vddpa designation(= VDDRF1V5 or VDDSMPS) and why it is not connected anywhere. I also didn't find any information about vssrf. do you have a recommended connection scheme?

[TDK · Accepted solution]

A lot of these questions are answered in the reference manual.

https://www.st.com/resource/en/reference_manual/dm00530369-stm32wlex-advanced-armbased-32bit-mcus-with-subghz-radio-solution-stmicroelectronics.pdf

> The power supply diagram shows the vssa pin of the chip, but it is not specified in the Pinout.

VSSA is the analog ground. It is the return path for VDDA. Connect to ground.

> It is also not clear the vddpa designation(= VDDRF1V5 or VDDSMPS) and why it is not connected anywhere.

VDDPA is the power for the power amplifier. Connect to VDD. See "Figure 6. High output power PA" in the reference manual.

> I also didn't find any information about vssrf. do you have a recommended connection scheme?

VSSRF is the return path for VDDRF. Connect to ground.