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Is there specific standard ways to generate clocks from oscillators? Referring to generating a square-wave clock from a sinusoidal oscillator output.

I can think of a few circuits involving diodes as well as using a chain of op-amps as comparators that could produce a square wave.

However, both have drawbacks, such as the voltage reference in a comparator drifting resulting in jitter on the output clock over a temperature range.

Are there industry standard schemes for creating clocks from an oscillator output?

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  • \$\begingroup\$ Often a digital buffer chip is all the amplifier you need. \$\endgroup\$ – The Photon Jul 26 at 21:57
  • \$\begingroup\$ Your question is not clear. Are you asking how to make a square-wave clock signal from a sinusoidal oscillator signal? \$\endgroup\$ – TimWescott Jul 26 at 21:57
  • \$\begingroup\$ @TimWescott Yes, amended. \$\endgroup\$ – Kirill Safin Jul 26 at 22:01
  • \$\begingroup\$ @KirillSafin If you lowpass filter the sine wave and then compare that to your sine wave with a comparator then you won't get any drift, this will give you a clean 50% on and 50% off square wave. Assuming that you are within the operational range of the comparator. Notice how I am not saying op-amp. - I don't know if this is an industry standard so.. a comment it is. \$\endgroup\$ – Harry Svensson Jul 26 at 22:08
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If you're not too fussy about duty cycle or jitter, a buffer with a Schmitt-trigger input will convert the sine to a square, assuming correct biasing and sufficient amplitude.

If you are fussy about those things, then use a PLL with a post-divide, which can give you perfect symmetry and also remove some jitter in the process. (Search for 'jitter cleaner PLL'.)

I'm going to assume you don't care about skew. If you do, speak up.

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I don't think there is an overall industry standard, although I'm sure that there are smaller markets where one thing or another s standard.

As mentioned, comparators or just buffers can work. How hard you work to get the clock jitter down is going to depend on how far you need the clock jitter to be down -- oftentimes the short-term clock jitter (which is all that you're going to affect with a noisy threshold) isn't as important as longer-term variations.

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