cancel
Showing results for 
Search instead for 
Did you mean: 

Designing with STM32L496

shibin
Associate II

Hello Team,

We are planning to use the MCU STM32L496QGI6 for one of our new projects.

The MCU will be powered from a 1.8V source (since all external peripherals are working in 1.8V only).

One of the SPI slaves is working in 3.3V, so we are planning to use the SPI on the PG Port as the PG port is powered by the VDDIO2 power supply.

Is there any issue if the main VDD and all other power supplies are at 1.8V and only VDDIO2 is at 3.3V? (the datasheet says the VDDIO2 is independent of VDD).

Also, this 3.3V SPI slave will not be functional at all times.

So the power to the 3.3V will be turned off to save the power. Since the VDDIO2 is also powered from the same power supply, the VDDIO2 will be at 0V if the SPI slave is not used even when VDD is preset at 1.8V.

Is there any problem with the MCU in keeping the VDD at 1.8V and VDDIO2 at 0V?

The VDDIO2 will be powered to 3.3V once we need the SPI slave.

1 REPLY 1
S.Ma
Principal

check carefully the datasheet electrical information, in particular the power up/down supply voltages constrains to know if your configuration is ok or ko. Check the errata sheet to confirm.