USB
Regulator
USB
XCVR
USB
Controller
USB0_DM
USB0_DP
VDD
VOUT33
VREGIN
TYPE A
D+
D-
VBUS
C
stab
To PMC and Pads
Chip
VSS
Charger
Li-Ion
Si2301
Figure 3-48. USB regulator Li-ion use case
3.9.1.2.3 USB bus power supply
The chip can also be powered by the USB bus directly. In this case, VOUT33 is
connected to VDD. The USB regulator must be enabled by default to power the MCU,
then to power USB transceiver or external sensor.
USB
Regulator
USB
XCVR
USB
Controller
USB0_DP
USB0_DM
VDD
VOUT33
VREGIN
TYPE A
D+
D-
VBUS
Cstab
To PMC and Pads
Chip
Figure 3-49. USB regulator bus supply
Communication interfaces
K22F Sub-Family Reference Manual, Rev. 4, 08/2016
124 NXP Semiconductors