Weird Oscillator Problems

[CocaColaKid]

I just talked with Jeff and ME Labs and asked him if he has seen this problem and he said yes. I guess some people don't even run caps. I checked the clkout and noticed a lot of noise when the caps were in circuit. Once removed the wave was nice and smooth. I tried this will about 8 different boards and all of them had the same results. I guess it really depends on the crystals charateristics if you need the caps or not. I tried a resonator and noticed a big difference in the clkout signal. The crystal is so much more accurate.

[Mike, K8LH]

'Kid,

I've seen similar symptoms with LVP enabled in the configuration fuses and the PGM pin left floating...

Regards, Mike

[Ron Marcus]

You might be overdriving the crystal when set up properly. In the Microchip books, they talk about putting a resistor between Osc2 pin and the crystal. Unless it is a specially cut crystal, or your Uncle owns the crystal company, find one that works reliably.

Hope this helps,
Ron