Not sure if this is the right place to post this, but there seems to be other similar threads so here goes. I am planning on mounting my HTC Desire on my handlebars in a Ram Aquabox. I have a newly arrived Garmin 60csx for off road tracks, but have Copilot on the Desire for street mapping and voice guidance, finding fuel/accomodation/ATM etc, and also use it for music, net banking, Facebook updates, and all the other smartphone goodies. An issue with the Desire is battery charging while using the GPS software, many chargers can't keep up. I would like to hardwire the phone via a 5 volt regulator to the switched power from my battery so I know it will be reliable. NB The Desire needs to have the two usb data lines shorted, which tells it is connected to a high current power supply, and therefore draws full charge. If they aren't shorted, it thinks it is plugged into a computer and reduces the charge current to protect the usb port. Can I just solder a LM7805 voltage regulator onto the end of a Micro-USB cable (after cutting the usb plug off of course), then mount it in an aluminium enclosure under the seat or somewhere (to waterproof it and act as a heatsink)? This should provide a constant 5v at 1 amp, and for a few cents more I could wire 2 of them in parallel to give 5v 2amps, and so forth. It just seems too simple? A google search seems to show that I can, but if it is that simple why doesn't everyone do it, since the parts cost is about $10 and it's soooo simple? Did I mention it seems too simple? I've looked at a few off the shelf chargers, and the only ones that seem to do what I want are ridiculously expensive. eg http://www.powerlet.com/product/micro-usb-direct-to-battery-harness/485 at about $50. edit This is probably ok value for what you get, just I know it's only a few bucks worth of parts and some basic soldering. Any electronics gurus out there care to offer some advice?