A Flexible, Programmable, High-Speed Laser Driver IC for Optical Recording

Transport of high frequency write strategy signals from the main board to the optical pickup unit (OPU) becomes more and more difficult due to the rapidly increasing data rate in optical recording. Furthermore, power dissipation on the OPU increases, leading to large variations in ambient temperature. As laser efficiency strongly depends on operating temperature it is important to have accurate laser power control algorithms to obtain a constant writing performance. For this purpose a high-speed laser driver integrated circuit in standard Complementary Metal Oxide Semiconductor (CMOS) technology has been designed which is flexible for optical recording formats like Compact Disc-recordable/rewritable (CD-R/RW), Digital Versatile Disc (DVD-R/RW) and the new Digital Video Recorder (DVR). It features a differential, low voltage swing interface and digital laser power control based on a single parameter algorithm. The IC, with a silicon area of 13.7 mm 2 is intended for mounting on the OPU. Multi-track overwrite jitter of 8.5% was measured on DVR discs at 48 Mbit/s using a blue Nichia laser diode.