> I've used Analog Devices' ADM695 more than once for jobs like this. It > handles backup battery switchover as well as chip select gating and a few > other functions that are very useful in most small embedded systems. It has > performed flawlessly... Dallas also has some nice devices like the DS1210. Best regards, Alexandre Guimaraes -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body