Power supply for VDDIO on the reset

Hello AkiraO 

I recommend you to visit page 63 of ADXL366 (Rev.0). A new DS revision is on work for ADXL367 and ADXL366 merging some of these details and adding new insight.

AkiraO said:

I plan to supply VS and VDDIO from separate power supplies. When I set VS to 0V for reset, is it okay to keep VDDIO at 3.3V?

No, you should not keep one supply at GND and the other at different voltage level.

Even if Vddio and Vs are different they should transit between GND and their high value at the same time to avoid current surge. 




Hope this solves your inquiry, otherwise let me know how can I further help.

happy holidays,

Mario SM

Hi,

Thank you for your reply. I understand that VS should not be set to GND alone. However, this raises a new question. I thought that VS and VDDIO could be set to different voltages. What do you think about this? Do I need to set the VDDIO voltage to match the I/F and then set VS to that voltage?

Thanks & Regards,

Akira

Hello AkiraO there is no issue in setting Vs and Vddio at different voltages (within DS specified limits) as soon as any non of both is GND.

MarioSM said:

Even if Vddio and Vs are different they should transit between GND and their high value at the same time to avoid current surge. 

As an example:

Vs=1.1 and Vddio=3.3V is a correct supply configuration.

but, be sure that whenever you want to shutdown the supply you do it at the same time for both pins thus, you do not keep a configuration as:


 Vs=GND and Vddio=3.3V or  Vs=1.1 and Vddio=GND, incorrect shutdown and current surge issue


 Vs=Vddio=GND as a correct off state.

 keep in mind that you should not apply Vs without Vddio and vice versa.

 hope this solves your inquiry, let me know if you need further help and wish you some great vacation time these days.

Mario SM

Hi Mario,

Thank you so much for your support. We wish you all the best for this Holiday Season.

Thanks & Regards,

Akira