Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 8705728 | Shared protection scheme for multiple variable batteries | Qiangsheng Charssen Ge, Elizabeth Ellen Perry | 2014-04-22 |
| 6925178 | Returning ringing signals through the tip amplifier of subscriber-line interface circuitry | John Gammel, Dean M. Umberger | 2005-08-02 |
| 5631797 | Overvoltage protector | Dean M. Umberger | 1997-05-20 |