Chip Drives Blue Laser Diodes In Super-High Data Storage Devices

Low power dissipation and a high level of integration are two of the key claims made for the EL6250C chip, a driver circuit developed specifically for use with violet/blue laser diodes. Blue laser technology is poised to usher in a new generation of data storage devices capable of holding several times more information than existing red or IR light-based versions of CDs, DVDs and DVRs. The EL6250C blue laser diode driver achieves its higher energy efficiency by using two supply voltages, with the internal logic operating from 5V, while the blue laser diode threshold of 5V requires the output stage to run at greater than 6V. The net result of the two-supply design is power dissipation of roughly 470 mW (typ.) versus about 620 mW for existing one-supply circuits. The new driver circuit also reduces the component count required by blue laser storage devices by integrating on-chip the current channels needed for read, erase, bias and write laser drive power levels, as well as a high frequency modulator (HFM) oscillator with high-speed laser driver output. The EL6250C blue laser diode driver comes in a 24-lead QSOP package costing $3.60 each/10,000. For more details, contact Steve Sacarisen at ELANTEC CORP., Milpitas, CA. (408) 945-1323, ext. 345.