1 chip 1KHz xtal osc?

[John Fields]

available?

Yeah, agreed, I clicked on "send" too quickly, my apologizes.
Say a pic 16F and a 4/8/10/12MHz crystal (still close to $1, no ?) ;+)

 

[Mike Harrison]

PIC10F does not have an external oscillator option.

 

[Roger Hamlett]

PIC10F does not have an external oscillator option.

Look at the SPG8640 and 8650 units. Programmable dividers and oscillators
in one package.
Any of the 8pin PIC's (12F675 for instance), would give a 'four part'
solution (crystal, two capacitors and the PIC).

Best Wishes

 

[Spehro Pefhany]

How do you get an accurate 1KHz from a 32.768KHz crystal?
It requires a division ratio of 32.768
Or if you actually mean a 32.000KHz crystal, then where are they readily available?

Dave

Digikey has 4 types in stock from 2 manufacturers, thousands of pieces
in total.

EG. http://rocky.digikey.com/WebLib/ECS/Web Data/ECS-31.pdf

0.83 US ea. one-off.

Best regards,
Spehro Pefhany

 

[David L. Jones]

Ah yes, so they do, Digikey have one 32.000KHz crystal.
I have not seen them available in Australia here (nothing unusual
there!)
Looks like a cheap option combined with the 4060. Not a "low parts
count" solution though, but cheap.

Dave

 

[Rich Grise]

Ah yes, so they do, Digikey have one 32.000KHz crystal.
I have not seen them available in Australia here (nothing unusual
there!)
Looks like a cheap option combined with the 4060. Not a "low parts
count" solution though, but cheap.

Dave

How is "four" not "low parts count"?

 

[Rich Grise]

Remember the old crystal holders that you could open up and take the
crystal out? I saw an article about how you could actually grind
them to trim the frequency. That'd be kinda cool; you get an old
80-meter transmit crystal, and grind it to 4,096,000 Hz.

;-)

 

[mike]

I need a lowest possible parts count 1KHz square wave oscillator.

Must use crystal timing with accuracy as good as reasonably attainable
without use of oven..

To do this, I assume it is best to start with the highest frequency
crystal possible, as each divide down increases resolution.

Power requirements are open.

Can anyone please advise regarding the most suitable circuit design?

With appreciation,

Mark

With such lack of specificity, you're likely to get only a ringside seat
to a pissing match...like the one in this thread.
How about specifying what you want?
Short term accuracy?
Long term accuracy?
Cycle to cycle jitter?
Cost?
Power?

Given the openness of your spec...
One part > Custom 1Hz. clock module, maybe GPS derived.
two parts > Pic processor with a TCXO. Jitter ain't gonna be good.
Pic means pic, avr, any other...
Most any watch chip should have 1 Hz. somewhere. Just hire someone to
wear it to keep the temperature stable.

Now, what do you really want?
mike


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[Hal Murray]

two parts > Pic processor with a TCXO. Jitter ain't gonna be good.

Why won't the jitter be good?

I'm assuming the software is written in assembly level where
you can/must count cycles.

 

[Tim Shoppa]

[...]

At one point I had some surplus 1kHz electric tuning forks. Those
would've required no divider, nor even a chip...

My dad had a mid-60's electric watch (Bulova Acutron), I think it was a
360Hz tuning fork in that one. It hummed quite nicely.

Tim.