EL6240C

The EL6240C is a combination read + 2 write level laser driver and IV amplifier, with an extra read + oscillator ROM channel for use in dual-laser 'combo' applications. A separate (amplitude and frequency) oscillator modulates the selected output for laser noise reduction dur-ing read or write.

The EL6240C CD pin, when high, selects the CD (write) laser. Positive current supplied to the IIN lines, through a user selected external resistor,allow the full scale range of each amplifier to be matched to the full scale range of the users control DACs. When the write laser is selected, and the WEN pins are switched low, the respective current is summed to the output with 1ns rise and fall times. When the CD pin is low, the ROM laserdiode is driven by output I_OUT2, and no current will appear at output I_OUT1.

The 100mAP-P (max) oscillator EL6240C is switched on and off by the OSCEN line. The CD line allows the oscillator to operate at different ampli-tudes and frequencies for each laser.

The entire chip EL6240C is powered down when ENABLE is low. The user can define the gain of the I/V amplifier. With a slew rate of 200V/s, the I/V amplifier can normally settle to 1% within 30ns.