Laser Diode Driver w/ Waveform Generator

The EL6935B is a highly integrated laser diode driver designed to support multi-standard writable optical drives. It accomplishes this by incorporating a waveform generator wherein the diode currents and timing details can be programmed before operation. The generator inspects the NRZ serial data waveform and generates programmed waveforms in recognition of 3, 4, 5, or 6 or more clock periods of space changing to 3, 4, 5, or 6 or more clock periods of mark, and vice versa. The part also has an IV amplifier with concurrent read and write sampling. The gains of the IV amplifier are programmable, eliminating the need for external potentiometers.

Features

• Completely programmable laser diode driver

• 500mA maximum total output

• 10-bit x 10-bit multiplying DAC output provides 10-bit full

scale adjustment and 10-bit resolution at any full scale

output

• 55psec timer resolution

• Two laser outputs allows read/ write DVD and CD

combinations

• Programmable waveform values support CD-R, CD-RW,

DVD-RAM, DVD-R, DVD-RW, DVD+R, DVD+RW, and

Blue

• Two analog inputs support slope and read APC

• HFM oscillator programmable to 100mAP-P from 100MHz

to 500MHz

• PLL allows reduced-frequency clock on flex cable

• Separate serial input works up to 100MHz

• Dual sampled IV amplifier with programmable sample and

gain selects

• Programmable DC output when HFM is off

• Pb-free available

Applications

• Combination DVD writable and CD writable drives

• DVD camcorders

• DVD video recorders