You don't really have to design a FF, you can just get one from TI for example (www.ti.com/sc). Keep in mind, if you are using any rails in your circuit >5V, you will need to stick a NPN transistor on the output of your FF to switch on the P-channel mosfet. If you are just using +5 lines, then you are ok. Quoting Josh Koffman : > Hmm...probably wouldn't work so well, half of the case is clear, so > ambient life would be a huge problem. I don't think the solution needs > to be that complicated though. Seems like something like a flip-flop > might work, but I lack the the expertise to design one. > > Thanks again! > > Josh > -- > A common mistake that people make when trying to design something > completely foolproof is to underestimate the ingenuity of complete > fools. > -Douglas Adams > > Richard Prosser wrote: > > > > How about a light operated switch then? > > -- > http://www.piclist.com#nomail Going offline? Don't AutoReply us! > email listserv@mitvma.mit.edu with SET PICList DIGEST in the body > ---------------------------------------- This mail sent through www.mywaterloo.ca -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body