Dave explains the Dickson Doubler building block circuit. a.k.a diode charge pump. Use a spare microcontroller pin, some diodes, and capacitors to create a useful voltage doubler or voltage multiplier. EEVblog Main Web Site: http://www.eevblog.com/ EEVblog Amazon Store: http://astore.amazon.com/eevblogstore-20 Donations: http://www.eevblog.com/donations/ Projects: http://www.eevblog.com/projects/ Electronics Info Wiki: http://www.eevblog.com/wiki/