I'm building an internet radio based on Hifiberry Amp+ with Volumio. I want to add a power on/off button to my project and I have found the ATXRaspi board which give this feature to the raspi. Unfortunately it's made to be use with the 5v micro usb and not a 12-18v through Hifiberry Amp+.
Is there a similar card that could be use to have a full on/off power button or have you heard of a similar project that I could re-use?
Thanks for your help.