B-WL5M-SUBG1 - RF Switch

[fabltd]

Hi All

I have the B-WL5M-SUBG1 board this uses the STM32WL5MOC mcu.

The datasheet for the B-WL5M-SUBG1 board says that the RF switch uses PINS:

• SW_RF
• PC_5
• PC_3

In the datasheet for the STM32WL5MOC I cannot locate SW_RF it does not exsit. 

Also in the datasheet for the B-WL5M-SUBG1 Table 18 I/O assignment there is no reference to SW_RF. I do see SW_CTL?

PC_5 and PC_3 are not in the table. I assume these are interal. 

Help...

[STTwo-32 · Accepted solution]

Hello @fabltd 

The SW_RF is the pin SW_CTL. (Just compare the description of both pins).

The PC5 and PC3 are IOs inside the STM32WL5MOCH module and dedicated to the RF front-end switch control. 

More details available on the schemtic pack here.

Best Regards.

STTwo-32 

[fabltd]

Thanks

Can you please point to where this is referenced in the datasheet?

Does SW_CTL have a pin name in example code I have seen this referenced as PC2 ?

[Tesla DeLorean]

https://www.st.com/resource/en/schematic_pack/mb1779-high-band-b02-schematic.pdf#page=5

I'd assume it connects directly to the RF Baseband, and indicates if the High or Low Power output is selected. So look at registers in the radio to control, not the STM32 MCU GPIO pins.

[fabltd]

Thanks for the schematic. Thats been driving me crazy.

Not sure why its missing from the docs. 

[STTwo-32]

Hello @fabltd 

Everything is mentionned on the schematic pack that i've attached to may answer and @Tesla DeLorean mentionned also.

For the schematic, you can always find it on the CAD RESSOURCES tab for all ST evaluation boards on the website.

Best Regards.

STTwo-32