20 MHz Crystal connections.

[Joe McGivern]

I'm putting together the boards for Nigels tutorials.

I bought some materials for the assembly of the boards and needless to say, 20 MHz oscillators were part of the order.

Main board No2 has a 20 MHz crystal. Two connections only are indicated on the circuit diagram.

The crystals I bought are manufactured by Fox and are type FS02 B 20.000 511. They have have four connections and are contained in a rectangular plastic enclosure. The crystal in the photo in Nigel's Tutorial is different.

I have looked at the data available to me and can't arrive at a decision as to how the crystal should be connected or if indeed it is unsuitable and another type of component should be used.

Can any one advise me please.

JMcG

 

[Mikebits]

Sounds like you got yourself an oscillator and not a crystal.

 

[jimmythefool]

You want one of these Joe...
https://www.rapidonline.com/Electro...stals/Quartz-crystals-(ACT)/29218/kw/Crystals

regards
Jim

 

[Joe McGivern]

https://uk.rs-online.com/web/search/searchBrowseAction.html?method=getProduct&R=2261853

How about this from RS components.
JMcG

 

[jimmythefool]

Perfect

 

[picasm]

The FSO-2 series datasheet is here:
https://www.electro-tech-online.com/custompdfs/2008/07/fso.pdf

It is possible to use it by connecting it's power (pin4) to 5v and ground (pin2) then the output (pin3) goes to your PIC OSC1/CLKIN pin which is pin16 on a pic16f628.

Do not connect anything to the PIC OSC2/CLKOUT pin. (unless you want to use the 5Mhz clock output for something)
Also, as shown in the FSO-2 datasheet, it needs a 0.01uF bypass capacitor near the oscillator power pins and do not connect it's pin 1 (E/D) to anything.

 

[Joe McGivern]

Yes Jim
I had a look, that seems OK. I've never dealt with that company yet and wasnt sure where they were located, But I'll sus it tomorrow. Thanks .

JMcG

 

[Joe McGivern]

Yes Jim
I had a look, that seems OK. I've never dealt with that company yet and wasnt sure where they were located, But I'll sus it tomorrow. Thanks .

JMcG

 

[jimmythefool]

Rapid Electronics are very good, although you have to spend £35 i think to avoid carriage..
I don't normally use xtals myself, I prefer to use the internal oscillator, but if your following a tutorial, your probably better off doing it as they say
Jim

 

[mneary]

If you put your location into your UserCP it would be easier to help you. I'm guessing you're not in the US because you're looking at rs.

I have a 20 MHz crystal I don't think I'll need.....

 

[Joe McGivern]

Thank you mneary for your kind offer.

I've added my location.

I think the cost of p&p would be prohibitive.

I've been scavenging and found a crystal made by AEL. Type X003L 22.118400M. Haven't fount the data on it yet. How would it compare to the one in the circuit diagram?

JMcG

 

[ericgibbs]

Thank you mneary for your kind offer.

I've added my location.

I think the cost of p&p would be prohibitive.

I've been scavenging and found a crystal made by AEL. Type X003L 22.118400M. Haven't fount the data on it yet. How would it compare to the one in the circuit diagram?

JMcG

hi Joe,
If you have a 4pin DIL 20MHz osc ic, it would be OK to use that in place of a standard 20MHz crystal.

Connect it as 'picasm' describes
You dont need the external low value caps.

EDIT: added a gif.

 

[jimmythefool]

Eric had a good idea...or you could always pop into Maplins.

 

[Joe McGivern]

Hi All
I was coerced into going on a shopping trip with my good wife. While she shopped, I went to Maplins and for a very small outlay(€1.19+tax each) I bought two.

Thanks Everyone.

JMcG