Power off connected device

[TeIk_3653391]

Hi,

We're using CYPD5225 at the host side in source mode and have to cope with power hungry devices. There is need to power off these devices completely to reduce wear and tear and then re-enable later. This can be done easily by disabling the port as this disconnects the device and powers it down. 

This approach has a problem that the port stays disabled even when the device is disconnected, because PD firmware does not detect the cable plug-out. Is there way to disable power so that PD still detects plug-out of the device and the firmware can re-enable port? We've tried e.g. disabling VBUS only but this did not work.

Thanks!

[ShifangZ_26]

Hello,

May I know more details of "We're using CYPD5225 at the host side in source mode and have to cope with power hungry devices. There is need to power off these devices completely to reduce wear and tear and then re-enable later." ?

As you may know, CCG5 have capabilities to handle OCP,OVP,... and looking for detach and then resume back from PD, is it the one you are looking for? If yes, the concerns call back API is void app_conf_for_faulty_dev_removal(uint8_t port).

Best Regards,

Lisa 

[TeIk_3653391 · Accepted solution]

Hi,

We've a setup where devices are semi-permanently connected to the host and those devices need to be powered off when not in use to prolong their service life and to reduce heat generation and EMI. User is not expected to plug out the device to do this. However, we still must detect possible plug-out even in the non-powered state.

I found a bug in my code and have now managed to power off the device by disabling the VBUS supply and configuring Mux to a safe mode. The device is powered off and PD still detects correctly plug-out and resets the port.  We can re-enable the port simply by restarting the port. This feels somewhat a hack but it appears to work fine. I'll look into the "app_conf_for_faulty_dev_removal()" if it could offer a cleaner solution. Thank you!