/*** Switch Performance level 
 *** from PL2 to PL0
 ***/ 
    PM->PLCFG.bit.PLSEL = 0;
    while(PM->INTFLAG.bit.PLRDY == 0);

    /*** OR in the case the application won't require
     *** high performances, Performance Levels can be 
     *** DISABLED.
     *** !!! Modifying this bit implies that the 
     *** device is already in PL0 !!!
     ***/
    PM->PLCFG.bit.PLDIS = 1;