G569C

The G569C is a single chip solution for the various functions relating to laser diode operation in a CD-RW drive. The G569C integrates nine functional blocks in one chip. It has five voltage-to-current converters, one current-to-voltage converters which is called FSA, one OP-AMP, one eight-channels D/A converter, and one voltage subtracter with output clamping capability called Dalpha.

Three of the five V-to-I converters provide the laser diode currents for Read, Write, and Erase operations, respectively; another one of the V-I converters provides the Cagain current; and the other one provides Deltap current which can selectively shunt a certain amount of laser diode current for write operation. For the Write and Erase operations, the voltage to current conversion ratio can be adjusted using an external or internal DAC resistor array. The FSA circuit performs integration on the output current of an external photo diode, and sample-and-hold the peak voltage. It is used to monitor the laser diode power. The internal eight-channel D/A converter is used to provide the input voltage for above functional blocks.

The G569C is available in a 48-pin SSOP surface-mount package.