649 Oscillating Bones
649 : Oscillating Bones
- Author: Uri Shaked
- Description: A stylish ring oscillator built from SkullFET transistors
- GitHub repository
- Clock: 0 Hz
How it works
A simple yet stylish ring oscillator that uses a chain of 21 SkullFET inverters to generate a square wave output. Based on simulation, the oscillator should have a frequency of around 90 MHz.
How to test
Connect an oscilloscope to the osc_out (ou_out pin 0) pin and enjoy the show. You can also observe the divided frequency outputs on osc_div_2, osc_div_4, and osc_div_8.
Simulation results
The following graph shows the output of the oscillator and the divided outputs. It was generated by running make -C sim and patiently waiting for the simulation to finish:
The outputs are shifted by 2 volts to make them easier to see in the graph. "uo_out[0]" is the main output of the oscillator, and "uo_out[1]", "uo_out[2]", and "uo_out[3]" are the divided outputs.
Note that the simulation results do not include all the parasitics, only the main ones. The actual frequency of the oscillator will probably be lower than the simulated one.
IO
| # | Input | Output | Bidirectional |
|---|---|---|---|
| 0 | osc_out | ||
| 1 | osc_div_2 | ||
| 2 | osc_div_4 | ||
| 3 | osc_div_8 | ||
| 4 | |||
| 5 | |||
| 6 | |||
| 7 |