S2-LP

[adamgarofs]

Hi, I'm working on a pcb for a student designed 3U CubeSat. We are looking at using your s2-lp transceiver. In the datasheet you include an application diagram, however the components are not given any values. Are you able to provide the capacitor and inductor values for this circuit at 433MHz? I've included the circuit below, taken from page 7 of the datasheet attached. If you cannot provide the values, can you please point me in the right direction? Anything helps, Thank you!

[Peter BENSCH · Accepted solution]

Welcome @adamgarofs, to the community!

The S2-LP can operate in four different frequency ranges, which is why no parameters for the passive components are shown in the example diagram. However, you will find a concrete implementation in the STEVAL-FKI433V2 evaluation kit, which was dimensioned for 433 MHz. BOM and schematics can be found in tab CAD Resources.

Hope that helps?

Good luck!
/Peter

[adamgarofs]

This was extremely helpful, Thank you! Just one final question that came up when reviewing the Eval kit you linked, some of the components such as C38 have values NM, does this mean Not Mounted? I haven't encoutered this before. If it is not mounted, why not? should I keep it unmounted in my circuit?

Thanks again!

[Peter BENSCH]

Correct, NM aka DNP stands for Not Mounted / Do Not Populate.

The reason is the universal use of the eval board, which can also be used for 868MHz if you change the printing (well, that's not really function-determining, but human-readable) and some components are changed/equipped. In your example C38 is not equipped in the 433MHz version and L5 has 27nH, while at 868MHz there are 1.8pF connected in parallel to 18nH.

Regards
/Peter