Hi,
I started a Circuit/PCB design with STM32WL55CCU (UFQPN48) to work at 433MHz.
I was referred to ST design for low band/Hight power and to AN5457.
But I am style missing for some information:
- What is the PA impedance at 433MHz for UFQPN48 package?
- In AN5457, the recommended value of L6 between 300MHz and 500MHz is 68nH. Why in all ST circuit design (low band) L6 is set to 56nH?
- Is the order of C4 and L3 has any influence on the circuit (some time C4 is before L3, and some time C4 is after L3)
- In the different ST circuit design, the CLC PI filter an matching (C8/L4/C7) is not accorded to 50ohm. Is it normal?
…..
After making some test with the nucleo board wl55, I cannot find the same range like I had with other RF433 module. It is look like RF circuit is not optimised or …. Is anybody have the same observation?
