RT1170 External POR

[Eugene3]

How long should external reset IC assert POR_B on the power up sequence?

I plan to use internal DCDC in RT1170. So I think external reset IC should assert POR_B until DCDC_DIG(for VDD_SOC_IN) and VDD_LPSR_DIG stable.

But I couldn't find the time spec in the DCDC section.

[Omar_Anguiano]

Hello
I hope you are well.

The POR_B input must be immediately asserted at power-up and remain asserted until the last power rail reaches its working voltage.

Best regards,
Omar

[Eugene3]

Hi @Omar_Anguiano 

Thank you for your replying.

How long does it take for the internal DCDC output to reach working voltage?

[Omar_Anguiano · Accepted solution]

Unfortunately, we don’t have this specific parameter. I apologize for the inconvenience this may cause you.
You could use as reference the PMIC sequence but you will also need the PSWITCH delay.

[Eugene3]

Thank you I understand.