Details of Power down sequence of STM32N657X0H3Q

[Tejas_P_R]

Hi All, In datasheet of STM32N657X0H3Q controller only power-up sequencing details are shown., Is there any power down sequencing is required?

If Yes, Please suggest the document which gives complete information of power down sequencing. 

[RomainR.]

Hello @Tejas_P_R 

For the power-up conditions, proceed in this order: 1, 2 and 3.

1. Apply VDD and VDD18AON (VBAT connected to VDD if no external battery is used), this will give the output PWR_ON=1.
2. Apply VDDCore (in external SMPS bypass using PWR_ON) and VDDSMPS  in internal SMPS.
3. Then apply the other supply: VDDA18PLL, VDDIOx, VDDA18PMU, VDDA33USB, VDDA18USB, VDD33USBCC, VDDCSI, VDDA18ADC, VREF+

For the Power-down, follow the procedure in reverse order 3, 2 and 1.

Best regards,
Romain,

[Tejas_P_R]

Hi Romain,

Thanks for your reply...!

We will follow the power-up sequence as mentioned in datasheet, But If we are not going to use the power down sequencing and turning OFF all power supply at once will affect any functionality?

 

Regards

Tejas

[RomainR.]

@Tejas_P_R 

In this case, you do not proceed with a power-down sequence, but with a complete direct shutdown.
This will not cause any problem.

Best regards,

Romain,

[RomainR.]

Hello @jczar 

The order of VDD and VDDA18AON does not affect the sequence, and there is no timing specification between the two voltages.

You can also refer to AN6000, section 3.2 System power‑up / uncontrolled power‑down sequence.

We also plan to improve power-on and power-down figures in a next version of the AN5967 for.

Best regards,

Romain,