USB_VBUS
Posted: Tue Jun 19, 2018 9:11 am
Long time no see,
Here is my question: I want to have only usb Input to the xmos board, no output. But I have connected the vbus via a diode to the power input of my schematic(custom board) so that it does not conflict with the other 5V input. Do I still need to connect the USB_CBUS to the USB_VBUS pin? I did read the document:"
If you use the USB PHY to design a self-powered USB-device, then the device must
be able detect the presence of VBus on the USB connector (so the device can
disconnect its pull-up resistors from D+/D- to ensure the device does not have
any voltage on the D+/D- pins when VBus is not present, “USB Back Voltage Test”).
This requires USB_VBUS to be connected to the VBUS pin of the USB connector as is
shown in Figure 15."
But I am not sure whether I should still make this connection. Again- I am going to be having usb Audio going to the board, but nothing going out and it will use the 5V to power itself directly going to the buck converters
Here is my question: I want to have only usb Input to the xmos board, no output. But I have connected the vbus via a diode to the power input of my schematic(custom board) so that it does not conflict with the other 5V input. Do I still need to connect the USB_CBUS to the USB_VBUS pin? I did read the document:"
If you use the USB PHY to design a self-powered USB-device, then the device must
be able detect the presence of VBus on the USB connector (so the device can
disconnect its pull-up resistors from D+/D- to ensure the device does not have
any voltage on the D+/D- pins when VBus is not present, “USB Back Voltage Test”).
This requires USB_VBUS to be connected to the VBUS pin of the USB connector as is
shown in Figure 15."
But I am not sure whether I should still make this connection. Again- I am going to be having usb Audio going to the board, but nothing going out and it will use the 5V to power itself directly going to the buck converters