Regulator selection for battery-powered UHF RFID reader

[YBAYR.1]

Hello, as I mentioned in the title, I'm designing a battery-powered UHF RFID reader. This is a challenging project for me; I'm pushing the limits.
MCU: stm32wb52cg
UHF RFID: ST25RU3993
Battery: li-ion (18650)
I'm using the ZigBee feature of the MCU. My question is, I need a design that's compatible with both batteries and works at 2.5V levels. Therefore, what kind of power circuit should I create? If I install a 4.2V battery, I need to use a step-down converter. If I use li-ion (18650), I need to use a booster. What do you think I should do?

2-Is a switching regulator used in a UHF RFID circuit?

3- I need to make a booster with the li socl2 battery. When the battery drops to 2v, should I make a step up for RFID reading performance?

[Peter BENSCH]

The UHF readers ST25RU3993 are unfortunately already on NRND (Not Recommended for New Design), intended only for ongoing projects, and therefore really should no longer be used in new designs. Otherwise, it can and will happen that you finish the design and can no longer source the readers.

Regards
/Peter

[YBAYR.1]

Yes, I will adapt my design to Impinj. Thank you. Do you have any suggestions on the power side? How to maximize power savings between 4.2V and 2V?

[Peter BENSCH]

I am only partially familiar with the specifications of Impinj, but for such a reader, you need relatively high power in TX mode, so an inductive switching regulator seems to be the best approach.

With a buck regulator, you could permanently regulate to the lowest input voltage, in your case 2V, e.g. with the STPS01, which can also do 100% duty cycle.

Alternatively, you could also use a positive buck-boost regulator such as the STBB1-AXX, which boosts your input voltage range of 2...4.2V to 3.3V, for example.

Regards
/Peter