Timing for VDD vs VDD_GPIO

[sssergsss]

Hello, 

Per the datasheet, VDD_GPIO must be applied after VDD has been applied.  Is there a minimum or maximum time? 

For example, can  VDD_GPIO be turned on 1 second after VDD is applied? 

Thanks

Sergio

[Simonr]

Hi Sergio

Applying VDD_GPIO at the same time as VDD is fine. VDD_GPIO shouldn't be powered alone, that's what matters.

Best regards,

Simon

[sssergsss]

Hi Simon, 

Both VDD and VDD_GPIO will be generated obviously from different supplies since they will be 3.8V and 1.8V respectively but voltage will be applied to the input of those supplies at the same time.  So it doesn't matter if the final voltage is +/-1mS from each other?  I don't want to add sequencing circuitry to the 1.8V if not required. 

Thanks

Sergio

[Simonr]

Hi Sergio

This should be fine, as long as VDD_GPIO isn't powered by itself at any point.

Best regards,

Simon