1 Reply Latest reply on Jan 30, 2015 8:46 AM by Intel_Alvarado

    Treating Edison USB Fault pin (on the system that doesn't include USB)

    hirohiro

      Hello,

       

      I have a question about Edison module,USB Fault pin(USB power fault input,connector pin no. is 19).

       

      If we would make a system that doesn't use USB,I wonder if we should treat "Fault" pin(USB power fault input) ,for example,

      should pull-up or other, or not (kept floating).

      I wonder that the power up sequence of the Edison module would be fail if we don't treat the Fault pin correctly or not.

       

      Does anyone know how to treat USB Fault pin if using on the system that doesn't include USB ?

      And ,I would like to know the important point about power management when we make the system with Edison module that doesn't include USB.

       

      I would appreciate if someone could reply to my question.

       

      Hiroyasu

        • 1. Re: Treating Edison USB Fault pin (on the system that doesn't include USB)
          Intel_Alvarado

          Hi hirohiro,

           

          I’ve found some useful information on the Edison Hardware Guide https://communities.intel.com/docs/DOC-23158

          It states that the FAULT pin is a USB power fault input (from external USB). It also states that Two signals PSW (pin 21), and FAULT (pin 19) from the ULPI controller are used to control the external power switch and monitor the overcurrent condition on VBUS. The PSW signal is active high and controls an external VBUS power switch or charge pump. The FAULT signal is active low. FAULT should be connected to GND if USB host mode is not used.

           

          According to this and what you are saying I believe you should connect it to ground. Take a look at the last line of the previous message “FAULT should be connected to GND if USB host mode is not used.”. You are not planning to use USB host mode right? If you don’t plan to use it I’d follow the instructions of the guide. In the guide you will find information of other ways to power the board.

           

          Regards

          Sergio