The EVM has a built-in USB interface based on the MSP432E401Y (U3) to allow the GUI, from the host computer, to communicate with the PMIC. The supply voltage required by the MSP432E401Y is generated automatically by the TLV73333PQDRVRQ1 (U11) and TLV73318PQDRVRQ1 (U12) LDOs which provides 3.3V and 1.8V from USB power, +VBUS. These voltages are available for supplying VIO for the PMIC (selectable from J32). Two SN74GTL2003 level shifters (U4, U6) are used in order to support the use case of the PMIC VIO of 1.8 V (the MCU IO will always be 3.3 V). In addition to the level shifters, the TS3A5018RSVR (U8) switch is used to apply the pullup voltages to the I²C lines only when the EVM is configured as controller (J22). Additional TS3A5018RSVR (U9) switch for SPI enable/disable. The application of the pullup resistors is for I²C mode only and is only intended for one board in a stack-up application. Note: in the stack-up configuration only controller board can have a valid +VBUS voltage on the board. This means that the controller board can have a connected USB cable supplying +VBUS and that controller board VCCA can be connected to +5.0V through J25, see Table 3-5. The EVM has 4 LEDs to indicate board power, on or off, and some pre-defined PMIC GPOs status. The signals are listed in Table 3-8.