Selecting the Main Voltage Regulator

In Active mode, the type of the main voltage regulator supplying VDDCORE can be switched on the fly. The two alternatives are a LDO regulator and a Buck converter.

The main voltage regulator switching sequences are as follows:

The Voltage Regulator Ready (VREGRDY) interrupt can also be used to detect a zero-to-one transition of the STATUS.VREGRDY bit.