How to connect 2 Pic's with the same oscillator

benni · Joined: 28 Jun 2012 Posts: 28

Hello,

Like it stays above in the subject I want to know how I can use one oscillator for two PIC's.

A friend of me said that I need to connect the oscillator with PIC1 normally and then I need to connect the output PIN of PIC1 to the input PIN of PIC2.

Like this:

Is that true/right?

Regards Benni

PCM programmer · Joined: 06 Sep 2003 Posts: 21708

This is good question for Google, because there is so much prior
discussion on this topic. Search Google for this:

benni · Joined: 28 Jun 2012 Posts: 28

Thank you,

i just found this:

And this is my answer :D

Thanks

Ttelmah · Joined: 11 Mar 2010 Posts: 19515

Yes. It has the 'downside' of slightly reducing the accuracy of the oscillator, unless you sit down and calculate the pin/track capacitance to the second PIC, and subtract this from the load capacitance used on the OSC2 pin. However provided the trace is short, the effect is small, and can usually be ignored.
Only 'comment' about the circuit is that it shows the load capacitors being connected to 'AGND'. Normally 'AGND, is reserved for analog circuitry, being 'analog ground'. The 'AGND' here needs to connect to the Vss pins on the pin, and 5v to the Vdd connections.

Best Wishes