CIRCUIT FOR DRIVING LASER DIODE

摘要

PURPOSE: A circuit for driving a laser diode is provided to make the laser diode constantly generate a maximum light output regardless of a change of a surrounding temperature. CONSTITUTION: An ALPC(Automatic Laser Power Control) circuit(200) sets a reference voltage matched with a variance by receiving an output signal of a light receiving diode and outputs the reference voltage. A laser diode driving circuit(202) outputs a driving current for driving the laser diode(201) depending on the reference voltage output from the ALPC circuit to the laser diode. The laser diode driving circuit is equipped with a laser diode driver(202a) outputting a laser diode driving current and a laser diode protector(202b) preventing an excessive laser driving current to damage the laser diode.