Fork me on GitHub

Project Notes

#246 CMOS Oscillators

Testing a 4-pin CMOS oscillator component.



4-pin CMOS oscillators - like the SaRonix NCH060C I’m testing here - contain all the circuitry necessary to produce an oscillation when voltage is applied.

Internal details are hard to find, but I’m guessing NCH060C is a combination of crystal resonator with CMOS inverter gate and buffer.

Tri-state Control

Some oscillators feature “tri-state” control on one pad (the NCH060C does not have this feature). This effectively inhibits the clock output, and may be used for testing or for master circuit control.

Typical behaviour is as follows:

Tri-state pin state Output
no connect or a logic high Enabled (clocking)
logic low Disabled (no clocking)

Test Circuit



SaRonix NCH060C


Pin Connections

Pin Use
1 tristate (n/a on the NHC)
8 output
14 +5V



According to my oscilloscope, the NCH060C (20MHz) is running at 19.9996MHz - marginal difference that may be as much to do with my scope as the component itself. The signal appears to not be a perfect square wave (but I may be reaching the limits of my scope).



The MCO-1510A is a 1MHz CMOS oscillator.


Pin Connections

Pin Use
1 n/a (tristate on other models)
8 output
14 +5V


Produces quite a clean square wave at 1MHz and 50% duty cycle.


Credits and References

Project Source on GitHub Project Gallery Return to the LEAP Catalog

This page is a web-friendly rendering of my project notes shared in the LEAP GitHub repository.

LEAP is just my personal collection of projects. Two main themes have emerged in recent years, sometimes combined:

  • electronics - usually involving an Arduino or other microprocessor in one way or another. Some are full-blown projects, while many are trivial breadboard experiments, intended to learn and explore something interesting
  • scale modelling - I caught the bug after deciding to build a Harrier during covid to demonstrate an electronic jet engine simulation. Let the fun begin..
To be honest, I haven't quite figured out if these two interests belong in the same GitHub repo or not. But for now - they are all here!

Projects are often inspired by things found wild on the net, or ideas from the many great electronics and scale modelling podcasts and YouTube channels. Feel free to borrow liberally, and if you spot any issues do let me know (or send a PR!). See the individual projects for credits where due.