| US 7,457,335 B2 | ||
| Fast loop laser diode driver | ||
| Richard Randlett, Palo Alto, Calif. (US) | ||
| Assigned to Exar Corporation, Fremont, Calif. (US) | ||
| Filed on Feb. 17, 2006, as Appl. No. 11/356,598. | ||
| Prior Publication US 2007/0195835 A1, Aug. 23, 2007 | ||
| Int. Cl. H01S 3/00 (2006.01) | ||
| U.S. Cl. 372—38.02 [372/38.01; 372/38.04; 372/38.07] | 22 Claims |
| 1. A laser diode driver circuit comprising:
a laser diode;
a photodetector adapted to receive optical feedback from the laser diode;
a closed-loop driver portion to provide a part of the current for the laser diode, the closed-loop drive portion output being
independent of the photodetector; and
a fast-loop driver portion to provide a second part of the current for the laser diode, the fast-loop driver portion using
the output of the photodiode to determine the output of the fast-loop driver portion;
wherein the closed loop driver portion provides part of the current for the laser diode during a read mode.
|