Test a Pierce Oscillator made with a minimum of components.
The Pierce oscillator is named for its inventor, George W. Pierce (1872-1956). It is a derivative of the Colpitts oscillator, and can be implemented using a minimum of components. Typically: a digital inverter, one resistor, two capacitors, and a quartz crystal.
The circuit I'm testing here is from KF5OBS. It features:
- BJT in place of the digital inverter
- takes advantage of the base-emitter capacitance to eliminate one capacitor
| Supply | Current |
|---|---|
| 5V | 2.6mA |
| 9V | 4.4mA |
I've tested with a range of crystals from 1Mhz to 16MHz, all oscillate satisfatorily.
Here's a trace with 7MHz crystal, 9V supply:
And 16MHz crystal, 9V supply:
