Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5457714 | Software controlled adaptive delta modulator | Melvyn Engel, Michael D. Bethel, Michael J. Smith | 1995-10-10 |
| 5208595 | Digitally controlled adaptive slew rate delta modulator | Melvyn Engel, Michael D. Bethel | 1993-05-04 |