Hi!
If I look at the datasheet of STM32WL31xx, I find Table 34. PA impedance which tells e.g. an optimum load impedance of 32 Ω // 16 nH in line 5 (high power, 868MHz)
This STM32WL31xx is (according to the datasheet) available in VFQFPN32 and VFQFPN48 packages.
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Now, while reading the AN5457 (RF matching network design guide for STM32WL Series), I get confused. This AN should cover the whole STM32WL31 and STM32WL33 series , right? So It should definitely be valid for my STM32WL31K8 in VFQFPN32 pakage?
Now to my questions:
1.) If the AN5457 is applicable, why does PA matching impedance measurements in Appendix A not contain any PA impedance measurements for the VFQFPN32 package?
2.) If I compare the datasheet PA load impedance given at the top of this post with the "next best" data of the UFQFPN48 package, the values are not anywhere near that of the values in the datasheet.
Can anyone tell which impedance value I should use as a starting point for calculating the matching network (for HP_TX @ 868MHz)?
Thanks
