differences of S32K148 VDD choose

[iysheng]

I want to design a board with S32K148. When I view the S32K1x Reference manual and reference designs. I wonder if I choose 5V power to S32K148 VDD, these pins releate enet levels still 5V or 3.3V ？

Besides I wonder why there are so many Bidirectional Voltage-Level Translator in hardware reference designs? 

[lukaszadrapa · Accepted solution]

Hi @iysheng 

S32K148 is single-supply device. It can be supplied either by 5V or by 3.3V. If ethernet module is used, the device must be supplied by 3.3V. If you need to connect some 5V logic in this situation, it is necessary to use voltage level translators. The pins are not 5V tolerant.

S32K3 family of devices solve this problem - the supply rail is split to A and B rings which can be supplied by different voltage.

Regards,

Lukas

[iysheng]

Thanks, I have looked S32K3X4EVB-T172 hardware schematic file, there removed these voltage level translators chips.