[time-nuts] Bye-Bye Crystals

[Hal Murray]

artgodwin at gmail.com said:
> I'm not after quality - I do have an application in mind but it doesn't need
> to compete with mass production. Just wondering if it's feasible to make
> something crude that will resonate.

Are you doing this for fun or ???

Feasible?  Sure.  Cheaper?  That depends.

The cost difference between a complete oscillator package and a simple 
crystal is tiny.  The osc is often cheaper if you include board space or 
engineering time.

Is your background digital or analog?  Do you want a sine wave or a clock?

My background is primarily digital.  If the chip you are using has 2 pins 
setup to drive a crystal, you can probably get it to run reliably by 
following the data sheet and/or app notes.  The usual recipe is 2 tiny caps 
and a big resistor.  (big in resistance, not physically big)

An advantage of using a crystal with the on-chip amplifier that I didn't 
mention last time is that you save the osc power if you power down that 
corner of the chip.

If you want a sine wave, you are out of my comfort zone.  I'd probably look 
in ham radio literature.

They make logic chips like a 74HCU04, U for unbuffered.  One of their uses is 
for making oscillators.  I've never done it.  Try google.

-- 
These are my opinions.  I hate spam.