CYC65632 self-powered usb hub reset

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JeME_1844631
Level 1
Level 1

Hi.

I designed a CPU with USB port connected to CYC65632 upstream port.

CYC65632 is designed as a self powered usb hub.

This main board is powered only with 3.3V.

How should I manage the ExtReset# pin to guaranty the presence of Vusb ?

Should I connect it to +3.3V (with a R + R//C bridge ?) ?

Thank

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1 Solution

Hi

As I mentioned, I don't have Vbus available so can't apply the typical schematic

To solve the problem, I connected reset pin to 3.3V via a RC bridge but ommitted the second resistance for the voltage divider

View solution in original post

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2 Replies
Sananya_14
Moderator
Moderator
Moderator
750 replies posted 500 replies posted 250 solutions authored

Hi,

Since it is a self-powered hub design, please connect VBUS from the CPU to the Reset pin of the hub with a RC circuit providing a delay of 10ms. This will hold the hub in reset till CPU is connected and VBUS is stable.

You could check to the 4607 DVK schematic for reference- https://www.cypress.com/file/117531/download

Best Regards,

Sananya

0 Likes

Hi

As I mentioned, I don't have Vbus available so can't apply the typical schematic

To solve the problem, I connected reset pin to 3.3V via a RC bridge but ommitted the second resistance for the voltage divider

0 Likes