I'm going to be using a laptop in my latest carpc, unfortunately its battery is totally dead so I'm designing a startup/shutdown controller which will act in very much the same way as the normal pc car power supplies.
When it senses ignition it will start the pc up by connecting some relays, when ignition is lost it will shut the pc down and after about 30 seconds will kill power totally to stop the pc draining the battery.
This is my schematic so far, anybody have any suggestions / comments?
