HX2VL power drops while OS boots #2

Tip / Sign in to post questions, reply, level up, and achieve exciting badges. Know more

cross mob
TeMa_2997106
Level 6
Level 6
Distributor - TED (Japan)
10 likes received 10 solutions authored 250 replies posted

I asked the following questions in the past.
https://community.cypress.com/t5/USB-Hosts-Hubs-Transceivers/HX2VL-power-drops-while-OS-boots/m-p/26...

I would like to eliminate this behavior of turning off VBUS.

The 11.11 Hub Port Power Control in the USB 2.0 standard has the following description.

HubPowerControl.jpg

If it does not implement Power Switch on your self-powered hub, Hub must implement the PortPwrCtrlMask implementation and the wHubCharacteristics Logical Power Switching Mode field for compatibility with previous versions.

The current circuit connects the Switch IC of VBUS and the PWR # signal of CY7C65632. My understanding is that if this feature is implemented, the CY7C65632 will not turn off VBUS by the PWR # signal even if it receives a SetPortFeature (PORT_POWER) request from the host. Is it correct?

Could you please tell me how to implement this feature in CY7C65632.

Thanks,
Tetsuo

0 Likes
2 Replies
MallikaK_22
Moderator
Moderator
Moderator
50 likes received 750 replies posted 250 solutions authored

Hello Tetsuo,

I'm sorry but I couldn't understand your requirement. Which feature do you wish to implement?

0 Likes
TeMa_2997106
Level 6
Level 6
Distributor - TED (Japan)
10 likes received 10 solutions authored 250 replies posted

Mallika-san,

I want to prevent VBUS drop when booting the OS.

I would like to know how to take measures while complying with the specifications.

Thanks,

Tetsuo

0 Likes