Need help calculating OSC cap values
I'm building a low power, low speed circuit using a 32.768kHz crystal but i'm not sure what cap values to use with the oscillator.
Does anyone know how to work out what values to use?
PIC: 18LF1320
CRYSTAL:
Frequency: 32.768kHz
Frequency tolerance: ±20ppm (@25°C)
Operating temperature:-10°C to 60°C
Shunt capacitance:2pf max.
Load capacitance:12.5pf
Insulation resistance:500MOhm @ 100VDC
Drive level:1µW max.
ESR (Equivalent series resistance):35KOhm
*edit*: I'm using a 32.768kHz crystal to facilitate accurate clock timing over longer periods, so that's why I ask about the caps because I have read that the wrong value will put the frequency out.
Last edited by Kamikaze47; - 26th June 2008 at 16:56.
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