i.MX8 USB VBUS voltage

[plymale_3]

Hello,

From the discussion forms, I can see that the i.MX6 requires a 5V USB VBUS signal.  I would like to know if this requirement is still valid with a i.MX8 processor.  Data sheet Table 10 (page 18) gives valid signal for VBUS as 0.8 to 3.6V.  Could this be connected to 3.3V?

From the data sheet section 3.9.14.1 it states "Each USBx_VBUS pin must be isolated by and external 30K 1% precision resistor."  Does this apply when connecting to the same 3.3V source as used to feed VDD_USB_3P3?

What is your suggested method of connecting USBx_VBUS using a 3.3V supply?  I would like to connect it to 3.3V though a 4.75K resistor.

Thanks,

Doug

[plymale_3]

Thank you weidong!

[weidong_sun · Accepted solution]

Hello @plymale_3 

See below, please!

Have a nice day!

B.R,

weidong

[hamzaatifi]

Hello @weidong_sun 

I found this reference design for the i.MX8 series, which shows that the USBx_VBUS pin has an internal 60 kΩ pull-down resistor.

Could you please confirm whether the i.MX93 has a similar pulldown resistor on the USBx_VBUS pin?

Thank you in advance!

Best regards,

Hamza

[Musadjan]

thanks.