Issued Patents 1989
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4862309 | Protection circuit for battery feed circuit | Toshiro Tojo, Kazumi Kinoshita, Yuzo Yamamoto | 1989-08-29 |
| 4827503 | Integrated ringing circuit and a ring trip circuit for the same | Kazumi Kinoshita, Toshiro Tojo, Yuzo Yamamoto | 1989-05-02 |
| 4827505 | Subscriber line interface circuit | Toshiro Tojo, Yozo Iketani, Mitsutoshi Ayano, Kiyoshi Shibuya | 1989-05-02 |