The power for the interface MCU is routed through two load switches: one for the VDD supply and one for the Universal Serial Bus (USB) supply. This makes it possible to disconnect the interface MCU from the power domain when not in use.
Figure 1. Interface MCU power switch
These switches are controlled a USB connected to the interface MCU USB connector (J2), and the state of the nRF only switch (SW6). See Operating modes for more information.