In CM4IO board schematic. The ID pin of the Micro USB connector is un-connected.
However, the USB_OTG_ID (101) pin of CM4 is connected to a resistor R8 2.2k ohm. The other end of resistor R8 is connected to VBUS pin of Micro USB connector.
There is another resistor R11 2.2k ohm between USB_OTG_ID (101) pin of CM4 and ground.
In my application board, I will also leave the ID pin of the Micro USB connector un-connected. I will also connect USB_OTG_ID (101) pin of CM4 to VBUS pin of Micro USB connector with a resistor R8 2.2k ohm in between and another resistor R11 2.2k ohm between USB_OTG_ID (101) pin of CM4 and ground.
However, the USB_OTG_ID (101) pin of CM4 is connected to a resistor R8 2.2k ohm. The other end of resistor R8 is connected to VBUS pin of Micro USB connector.
There is another resistor R11 2.2k ohm between USB_OTG_ID (101) pin of CM4 and ground.
In my application board, I will also leave the ID pin of the Micro USB connector un-connected. I will also connect USB_OTG_ID (101) pin of CM4 to VBUS pin of Micro USB connector with a resistor R8 2.2k ohm in between and another resistor R11 2.2k ohm between USB_OTG_ID (101) pin of CM4 and ground.
Statistics: Posted by TommyBills — Thu Jun 26, 2025 6:46 am