Issued Patents All Time
Showing 1–8 of 8 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6316882 | Electronic ballast having a stable reference voltage and a multifunction input for soft dimming and ON/OFF control | Nak-Choon Choi | 2001-11-13 |
| 6175218 | Power factor correction (PFC) controller | Nak-Choon Choi, Kyung-Hee Jang | 2001-01-16 |
| 6122180 | SMPS with constant power control circuit | Sang-Heum Yeon | 2000-09-19 |
| 5973458 | Sequential feedback control system for an electronic ballast | Nak-Choon Choi | 1999-10-26 |
| 5949229 | Power factor correction circuit having an error signal multiplied by a current signal | Nak-Choon Choi | 1999-09-07 |
| 5764039 | Power factor correction circuit having indirect input voltage sensing | Nak-Choon Choi | 1998-06-09 |
| 5726534 | Preheat current control circuit based upon the number of lamps detected | — | 1998-03-10 |
| 5642065 | Zero-voltage switching circuitry, as for use in resonant inverters | Nak-Choon Choi | 1997-06-24 |