> On the manual on page > 151, table 15.0 DS30292B You should get the latest data sheet. I don't know what the differences are, but I have DS30292C. > and in the following page I have understand that > the PIC should be used at lower voltage, and in particular I use the PIC at > 3,9 Volt. > > ... > > If at the end of this discussion the answer is "PIC CANNOT BE USEDWITH POWER > SOURCE LESS THAN 5 VOLT", for me is important, because I can decide to power > in other way. I'm not sure what you are trying to do, but tables 15-1 thru 15-4 quite clearly show the relationship between voltage and maximum frequency. I wouldn't know how to explain it any better. What about them don't you understand? ***************************************************************** Embed Inc, embedded system specialists in Littleton Massachusetts (978) 742-9014, http://www.embedinc.com -- http://www.piclist.com hint: The PICList is archived three different ways. See http://www.piclist.com/#archives for details.