The application note you have requested is available in Acrobat PDF format: APPLICATION NOTE 50: Proximity Detector Features Ultrasonic Transducers (PDF, 81kB) A free Acrobat PDF reader is available from: http://www.adobe.com/products/acrobat/readstep.html We Want Your Feedback! 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™. More Information   APP 50: Jul 09, 1998 ICM7555 Low-Power, General-Purpose Timer Full Data Sheet (PDF, 3MB) MAX406 Single, Dual, Quad, 1.2µA Max, Single-Supply Op Amps Full Data Sheet (PDF, 6.9MB)   Download, PDF Format (81kB)  AN50, AN 50, APP50, Appnote50, Appnote 50