Hi, Oscillation is not a problem if you simply make them outputs and connect them to nothing. I've been doing it for years. Len ----- Original Message ----- From: "David Duffy" To: Sent: Wednesday, August 28, 2002 5:25 PM Subject: Re: [PIC]: Unused pins > At 08:00 PM 28/08/2002 -0400, you wrote: > >In a message dated 08/28/2002 19:46:38 Eastern Daylight Time, > >bmoran@MILLENNIUM.CA writes: > > > > > That's what I *have* been doing, but since I'm committing this project to a > > > PCB, I want it to be done right. And I know that if the pins are ignored, > > > then there could be some issues with power consumption. CMOS is worse than > > > TTL for this. > > > > > > >Brendan, I've made a lot of PC boards where I ignored the unused pins. Power > >consumption was really never an issue because I was always running of a wall > >wart. Even so, I can't imagine that the power consumed by an unused pin > >would be significant. And I have followed the same procedure with the > >"other" micro-processor. > > Hi Sid, > It's not the power consumption as such, but the whole chip can oscillate and > behave badly when you let inputs float. It's just like leaving unused inputs on > CMOS gates floating - just asking for trouble. They (CMOS) have a habit of > latching up, heating up and dying. The increased power consumption is just a > symptom of the problem and should not be ignored. > Regards... > ___________________________________________ > David Duffy Audio Visual Devices P/L > U8, 9-11 Trade St, Cleveland 4163 Australia > Ph: +61 7 38210362 Fax: +61 7 38210281 > New Web: www.audiovisualdevices.com.au > ___________________________________________ > > -- > http://www.piclist.com#nomail Going offline? Don't AutoReply us! > email listserv@mitvma.mit.edu with SET PICList DIGEST in the body > > -- http://www.piclist.com#nomail Going offline? Don't AutoReply us! email listserv@mitvma.mit.edu with SET PICList DIGEST in the body