OTHER SEQUENTIAL CIRCUIT #1 – RING OSCILLATOR

THE CIRCUIT

A ring oscillator is simply any odd number (greater than one) of NOT gates connected together. It will generate a sequence of highs and lows at a rate dependent on the propagation delay of each NOT gate.

WHY NOT USE IT NOW?

This is a simple circuit so it seems like it would be a nice little project to do. However, the frequency that is generated is so high that if it were used to make an LED blink, one would not be able to see it. In fact, it would be too fast for the LED to respond correctly.

USES

It could be used in a circuit that requires a regular oscilatting input.

FURTHER RESEARCH

We could look at datasheets for NOT gates (7404) and find the propagation delay and calculate the frequency for any ring oscillator.

The 7404 chip created by Texas Instruments has a propagation delay of 22 nanoseconds. (http://www.ti.com/product/SN7404/description#parametrics)

On youtube, an experiment measured the progmeasured a not gate to have a propagation time of 20 nanoseconds.