On Wed, Mar 24, 2010 at 10:01 AM, vasile surducan <[email protected]>wrote:
> > > On Wed, Mar 24, 2010 at 7:30 AM, m...@watty <[email protected]> wrote: > >> Typically "over clocked" will fail at temperatures above 20C, or lower >> than 5V supply and on a percentage of parts. >> The amount possible to overclock will also be fewer devices, higher >> voltage, lower temperature as you raise clock speed. >> >> It's not worth the risk on reliability grounds. The next one may not >> work, there may be premature failure, or it will fail in summer. >> > > This time you have right. However, since the question purpose was hobby and > not production (my nose smell it) I can tell that 90% of the PIC works OK > overclocked as suggested in the temperature range mentioned in the datasheet > with external oscillator and external oscillator/internal PLL enabled > combination. > External oscillator above should not be undertand as an external HS/XT crystal, but a stand alone oscillator. > > The weak part of the PIC which is creating problems at high temperature is > the internal oscillator and analogical stuff (reference, A2D and the > comparator) > Internal oscillator above is not only the RC INTOSC but also the HS/XT which is using a logic gate inside the PIC. > >> >> On Mar 24, 1:33 pm, vasile surducan <[email protected]> wrote: >> > On Wed, Mar 24, 2010 at 3:22 PM, Sebastien Lelong < >> > >> > [email protected]> wrote: >> > > Hi guys, >> >> > > crystal. With 16 MHz Xtal, you have 16 * 4 = 64 Mhz, 4 being the black >> magic >> > > factor coming from PLL. >> > >> > > Now, what if I use a 20 MHz Xtal ?... Will PIC gets burnt ? Or will it >> just >> > > won't work ? >> > >> > 20MHz PICs works ok at 25MHz >> > 40MHz PLL (10Mhz XTAL) works at 48Mhz (12MHz XTAL) >> > >> > At 80MHz there is very low chance to work. >> > >> > >> > >> > > Cheers, >> > > Seb >> >> listen to Vasile! Assume in this case he is being kind! :-) >> >> -- >> You received this message because you are subscribed to the Google Groups >> "jallib" group. >> To post to this group, send email to [email protected]. >> To unsubscribe from this group, send email to >> [email protected]<jallib%[email protected]> >> . >> For more options, visit this group at >> http://groups.google.com/group/jallib?hl=en. >> >> > -- You received this message because you are subscribed to the Google Groups "jallib" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/jallib?hl=en.
