mpc5746r VDD_HV_IO_MAIN spec

[alistairhill]

The data sheet for the MPC5746R Rev 4 specifies VDD_HV_IO_MAIN as 3.5V to 5.5V but note 7 of Table 3 states "The pad are operative till 3.0V full performance. The IRC oscillator is supplied by this pin and it is setting the min voltage limit" implying that the IO is perfectly good with VDD_HV_IO_MAIN=3.3V nominal which would be much more convenient for my application.

The limitation appears to be the internal RC oscillator so is there a work round that would allow me to use 3.3V given that the RC oscillator is needed for startup and some of the peripherals, I am using an external clock

Thanks

[lukaszadrapa]

Hi,

there's no workaround. VDD_HV_IO_MAIN mus be 3.5V at least, typically 5V.

LVD_IO circuit does not allow us to operate this supply rail at 3.3V:

Regards,

Lukas