AD9660

a FEATURES 1.5 ns Rise/2.0 ns Fall Times Output Current: 180 mA @ 3 V, 200 mA @ 2.5 V Bias Current: 90 mA @ 3 V Modulation Current: 60 mA @ 3 V Offset Current: 30 mA @ 3 V Single +5 V Power Supply Switching Rate: 200 MHz Onboard Light Power Control Loops APPLICATIONS Laser Printers and Copiers Optical Disk Drives FO Datacomm 200 MHz Laser Diode Driver with Light Power Control AD9660 FUNCTIONAL BLOCK DIAGRAM WRITE PULSE WRITE CALIBRATE WRITE LEVEL T/H V:1 OUTPUT DRIVER OUTPUT LASER DIODE TRANSIMPEDANCE AMPLIFIER SENSE INPUT PHOTO DETECTOR DIODE BIAS LEVEL BIAS CAL BIAS T/H V:1 OUTPUT DRIVER AD9660 GENERAL DESCRIPTION The AD9660 is a highly integrated driver for laser diode applications such as optical disk drives, printers, and copiers. The AD9660 gets feedback from an external photo detector and includes two analog feedback loops to allow users to set “bias” and “write” (for optical disk drives) power levels of the laser, and switch between the two power levels at up to 200 MHz. Output rise and fall times are typically 1.5 ns and 2.0 ns to complement printer applications that use image enhancing techniques such as pulse width modulation to achieve gray scale, and allow disk drive applications to improve density and take advantage of pulsed write formats. Control signals are TTL/ CMOS compatible. The driver output provides up to 180 mA of current @ 3 V, 90 mA of BIAS current, 60 mA of modulation current, and 30 mA of offset current. The onboard disable circuit turn...