A family of semiconductor devices is formed in a substrate that contains no epitaxial layer. A watchdog timer included in the switching power converter controller is configured to countdown a timer unless it receives a reset signal from the host microprocessor. The peer to peer wireless terminal receives and measures the strength of the base station signal. The actions further include determining, based on the identifier of the item of media content and the timestamp, an amount of remaining time that the item of media content has to play. A method for preparing said membranes is also provided.