LASER POWER CONTROLLER OF OPTICAL DISC DRIVER

摘要

PURPOSE: A laser power controller of optical disc driver is provided to easily switch a driving power of a laser diode and a power and to simplify a constitution of a circuit by digitizing the laser power controller of optical disc driver. CONSTITUTION: A microcomputer feeds a voltage value into a voltage reference generating unit(200) as a digital signal. The voltage reference generating unit(200) offers a signal about the reference voltage value of a laser power into a reference pulse generating unit(210). A reference pulse from the reference pulse generating unit(210) is fed to a pulse width modulating unit(231) through an adder(220). The reference pulse fed from the pulse width modulator(231) is offered to a low band filter(232) by performing a modulation of pulse width with a sampling clock. An output of the low band filter(232) is fed to a base terminal of a transistor(Q) in a driving unit(240) to turn on. A power fed to an emitter terminal is supplied to a laser diode(D1). A data on an optical disc is recorded or read by a laser power generated thereby.