Re: [PIC]: Startup time for resonators by Matt Pobursky .

part 0 44 bytes This is a multipart message in MIME format part 1 1488 bytes content-type:text/plain; charset=iso-8859-1 (decoded 7bit) Brent, Here's a screenshot of a Kyocera PBRC-4.00 4MHz SMD ceramic resonator w/internal caps on startup. I tried it several times and it was very consistent. It looks like it takes about 600 uS from power-on. It tracks the 5V supply rail quite nicely. Since you want to are planning to use Sleep mode, the oscillator should start up very quickly based on what I see -- probably around 300 uS based on the 'scope shot. My CONFIG fuse is set to HS, since I found that in production units the oscillator starts more reliably than with XT using this particular resonator. Hope that helps. Matt Pobursky Maximum Performance Systems On Fri, 12 Jul 2002 09:22:39 +1200, Brent Brown wrote: {Quote hidden}>Does anyone have any figures for oscillator startup time using a 4MHz >ceramic resonator? Comparison to times for RC or crystal would be >great. > >I will be using a PIC16F877 sitting in sleep mode most of the time >until woken up by interrupt. To keep power dissipation lowest we want >it to wake up as soon as possible do it's thing and go back to sleep. >My client has previously used RC mode for this reason, but now needs >better timing accuracy. I have a feeling that a resonator will start >quicker than a crystal but I need to verify that. Lots of my other >projects use a 4MHz resonator with internal caps but haven't used >sleep mode. Maybe I'll write a test program later today nad try it >myself. > >Thanks. part 2 8865 bytes content-type:image/gif; name=Ceramic.gif (decode) part 3 144 bytes -- http://www.piclist.com hint: The list server can filter out subtopics (like ads or off topics) for you. See http://www.piclist.com/#topics