PICAXE 28x Resonator Capasitors

[-=GST=- Nemisis (cs/cz)]

the picaxe 28x is basically 16F873A so would an external resonator of 4mhz with two loading capasitors of 22pf be ok? and i have i got it set up right here:

 

[Sceadwian]

Resonator or crystal? Ceramic resonators are three pin devices and have built in load capacitors, so none would be needed, accuracy is less than a crystal though. For a crystal you should chose a crystal that was designed for the same load capacitance as your PIC, (which is easy) most common crystals that operate on fundamental frequencies use 18-22pf capacitors. You can use trimmer capacitors to fine tune the frequency if needed, though if you need trimmer caps for frequency it's probably a good idea to oven control the entire oscilator section. (Pic and crystal) Or use an external oven controlled oscilator.

 

[-=GST=- Nemisis (cs/cz)]

ok well i got a two pin crystal which is found here:

**broken link removed**

and so i need the load capacitors, its doesnt have to be accurate so thats not a problem. on the site it saysa load of 20pf, so would a 22pf be ok or could i use two 10pf capacitors in parrallel? i would prefer to only use the one, but i would use two if necessary.

 

[Nigel Goodwin]

The capacitors across the crystal aren't very crucial, 10pF's will be fine.

 

[-=GST=- Nemisis (cs/cz)]

alright then im gunna use a 22pf, have i got the setup right? and they arent electrolytic capacitors just regular ones?

 

[Nigel Goodwin]

alright then im gunna use a 22pf, have i got the setup right? and they arent electrolytic capacitors just regular ones?

If you can find a 22pF electrolytic, feel free to use them!