Xtal without MCU?

[kfitch42]

Mostly out of curiosity I was wondering how one would use a crystal oscillator(resonator?) without a microcontroller. In just about every microcontroller datasheet you see something similar to the attached image. What magic lives on the other side of those xtal pins? Is it something a noob like me could actually breadboard?

[mrflibble]

See for example http://en.wikipedia.org/wiki/Pierce_oscillator

[TerminalJack505]

Yes, this is something you can breadboard quite easily.  (High frequencies might be a problem on a breadboard, however.)

There are a few ways to go about it but most circuits use, in addition to the crystal, just a couple of inverters, a few resistors and a few capacitors.  Do a Google image search on "crystal oscillator circuit" to see some examples.

They make ICs specifically made for this too.  For example.  Notice (page 7) that all that IC really does is package-up the inverters.  You still need to provide the capacitors, resistors and crystal.

Finally, in case you aren't aware, they package the whole crystal and other necessary components up into a single package an call it a crystal oscillator.

[Bloch]

My first was with 74xx and 40xx IC´s


some thing like this look ok http://www.z80.info/uexosc.htm

[jimmc]

Try looking at crystal manufacturers application notes for ideas.

e.g. http://www.euroquartz.co.uk/Portals/0/pdf/tech-notes.pdf  (practical circuits start on page 5).

Jim

[HackedFridgeMagnet]

Spot the mistake.
edit: It's from the above tech sheet, which was actually interesting for a Xtal noob such as myself.

[c4757p]

Spot the mistake.

C₁ is an inductor and L₁ is a capacitor.

[marshallh]

74HCU04 + xtal is a common setup

http://www.nxp.com/documents/data_sheet/74HCU04.pdf

See page 8

[pspgeek]

Thanks. I was also looking to use a crystal to replace a (transistor + capacitor + etc) oscillator.