The nRF21540 DK has multiple power options.
The power options are the following:
- Universal Serial Bus (USB) connector J2 for the interface MCU (5 V)
- USB connector J3 for the nRF52840 (5 V)
- Lithium-polymer (Li-poly) battery connectors J6 or P27 (2.5–5.0 V)
- VIN 3–5 pin on P20 (3.0–5.0 V)
- External supply on P21 (1.7–3.6 V)
Figure 1. Power supply options
Note: A maximum current input of 0.5 A is recommended.