How to use USB_OE / USB Activate OE in STM32F0x2

[derektong]

Posted on July 02, 2014 at 14:23

I am using STM32CubeMx for STM32F0x2. In ''pinout'' page, there is a checkbox called ''Activate OE'' in USB. It occupy an GPIO pin (e.g. PA15) if it is enabled.

What kind of function provided by ''Activate OE''?

What is the recommended USB circuit if ''Activate OE'' is enabled?

[tsuneo]

Posted on July 02, 2014 at 16:49

On the RM0091 reference manual for STM32F0, this description is found.

30.4.1 Description of USB blocks

The output enable control signal of the analog transceiver (active low) is provided externally on USB_NOE. It can be used to drive some activity LED or to provide information about the actual communication direction to some other circuitry.

 

For ordinary USB circuit, this pin is not required.

I believe an isolator of USB line is the typical application of this pin function.

Tsuneo

[derektong]

Posted on July 03, 2014 at 08:12

Thank you