LASER DIODE DRIVING CIRCUIT AND A LASER DIODE CONTROL DEVICE INCLUDING THE LASER DIODE DRIVING CIRCUIT, ESPECIALLY CONCERNED WITH PREVENTING A LASER DIODE FROM BEING DAMAGED BY AN EXCESSIVE DRIVING CURRENT

摘要

PURPOSE: A laser diode driving circuit and a laser diode control device including the laser diode driving circuit are provided to prevent a voltage of an input end of a laser diode driving circuit from dropping at less than a predetermined voltage, and to determine a limit value of a driving current supplied to a laser diode, thereby preventing the laser diode from being damaged by an excessive driving current. CONSTITUTION: An ALPC(Automatic Laser Power Control) circuit(110) sets a reference voltage, and outputs the set reference voltage. A laser diode driving circuit(200) outputs a driving current for driving a laser diode(102) to the laser diode(102) of a pickup unit(100) according to the outputted reference voltage. A laser diode protecting circuit(130) is installed on an output end of the laser diode driving circuit(200) to protect the laser diode(102) from static electricity or a surge voltage generated when the pickup unit(100) is mounted or dismounted.