Ring oscillator with a digitally programmable frequency

A method for digitally programming a frequency of a ring oscillator, wherein the ring oscillator includes an odd number of inverting stages coupled input to output to form a ring, comprising:

• receiving a digital value associated with the frequency for the ring oscillator;
• and
• using the digital value to program a drive strength for each inverting stage in the ring oscillator;
• wherein programming the drive strength changes the propagation delay between inverting stages and thereby adjusts the frequency of the ring oscillator.

A semiconductor chip including a ring oscillator with a digitally programmable frequency, comprising:

• a semiconductor substrate;
• the ring oscillator on the semiconductor substrate, wherein the ring oscillator includes an odd number of inverting stages coupled input to output to form a ring;
• and
• a programming mechanism configured to digitally program the drive strength for each inverting stage in the ring oscillator, thereby changing the propagation delay between inverting stages and thereby allowing the frequency of the ring oscillator to be adjusted.

A computer system including a ring oscillator with a digitally programmable frequency, comprising:

• a processor;
• a memory;
• the ring oscillator, wherein the ring oscillator includes an odd number of inverting stages coupled input to output to form a ring;
• and
• a programming mechanism configured to digitally program the drive strength for each inverting stage in the ring oscillator, thereby changing the propagation delay between inverting stages and thereby allowing the frequency of the ring oscillator to be adjusted.