Working on a simple LoRA sensor which is powered by a lithium capacitor, I am wondering whether to rely on the internal SMPS or an external buck IC for stepping down voltage to improve efficiency.
My measurements of the internal SMPS indicate a efficiency of around 60% (if I assume a minimal consumption of 8.1mW)
Is this about right or am I missing something?
So it would be quite beneficial to add an external buck IC like the TPS63900 with >90% efficiency and 75nA Iq and step down to around 2V (LoRa in EU868 should still be operational), correct?
(In that case, should I turn off the internal SMPS for both SubGhz and normal operation?)
