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Power sequencing inconsistency

JensJorgen
Visitor

quote from hardware development application note -

"VDD3V3_USBHS must not be present unless VDDA1V8_REG is present, otherwise permanent
STM32MP15x lines damage can occur. It must be ensured by PMIC ranking order or with
external component in case of discrete component power-supply implementation."

this seems to contradict that (another quote) - 

"VDD3V3_USBFS is used to supply OTG_VBUS and OTG_ID (PA10) pins. Therefore,
VDD3V3_USBFS must be supplied as well when USB high-speed dual-role-port or USB
high-speed device is used. If not used, it must be connected to VDD."

along with quote - 

"VDD_DSI, VDD_PLL and VDD_ANA must be connected to VDD"

 

so essentially VDD= VDD_DSI = VDD3V3_USBFS = VDD3V3_USBHS 

Then VDD3V3_USBHS  WILL be 3.3V before VDDA1V8_REG is 1.8V will it not?

 

what i am essentially asking about is whether or not i can avoid having to use a whole other buck converter just to be able to supply VDD3V3_USBHS later after VDDA1V8_REG has reached 1.8V

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