I'm making a 5 volt portable regulated power supply (using LM7805 regulator IC) for Arduino UNO. I'm planning to use a USB connector as its output socket, this way I can just plug and power the Arduino via USB. My problem is where do I connect the USB sockets's shield ? As far as I know it should be connected to the ground if it is a host device - can we consider the power supply as a host device?
Note: I've asked this question in arduino.stackexchange and advised to get in here.