AD9664

The AD9664 is a laser diode driver for high performance CD-RW and DVD recordable drives. It includes four channels for four different optical power levels: the Read Channel generates a continuous output power level, whereas Channel 1, Channel 2, and Channel 3 can be used as write channels that can be controlled with an LVDS or TTL interface. The OSCEN pin is controlled by a TTL signal. All channels are summed at the selected LD output pin where Write Channel 1 can contribute a minimum 325 mA maximum output current, and Write Channel 2 and Write Channel 3 can contribute a minimum of 250 mA and 150 mA, respectively. The level of the output current is set by an external resistor, which converts this voltage into a current at the xSET pin.

An on-chip oscillator is provided to allow output current modulation and to reduce laser mode hopping. Four external resistors permit the setting of two distinct values for the frequency and swing of the oscillator. The oscillator can output up to 100 mA p-p of current (push-pull oscillator) with a frequency range of 200 MHz to 500 MHz.