Abstract: A MAX638 step-down DC-DC converter can be made to generate -5V from a +5V input. The application note you have requested is available in Acrobat PDF format: APPLICATION NOTE 18: Step Down DC-DC Converter Operates as Inverter (PDF, 1.1MB) A free Acrobat PDF reader is available from: http://www.adobe.com/products/acrobat/readstep.html Related Parts   APP 18: Jul 09, 1998 MAX638 5V Adjustable, CMOS, Step-Down Switching Regulator Full Data Sheet (PDF, 304kB) Free Samples Automatic Updates Would you like to be automatically notified when new application notes are published in your areas of interest? Sign up for EE-Mail™. We Want Your Feedback!   Download, PDF Format (1.1MB)  AN18, AN 18, APP18, Appnote18, Appnote 18