Patent ID: 8665681
Filing Date: 2014-03-04
Classification: G11B

Abstract:
1. An optical disc drive that uses a laser beam for recording data corresponding to a laser drive current pattern on an optical disc, the optical disc drive comprising: an optical pick-up including a laser diode generating the laser beam corresponding to the laser drive current pattern, and a laser diode driver having one or more current sources each including differential inputs and a single output that is connected to the laser diode and a respective first resistor connected between the differential inputs of each current source, the laser diode driver producing the laser drive current pattern based on a sum of one or more differential signals input to the one or more current sources via the differential inputs of the one or more current sources and outputting the laser drive current pattern to the laser diode, thereby driving the laser diode; a digital signal processor including a write strategy circuit producing a write strategy signal and one or more differential transmission drivers for transmitting the one or more differential signals based on the write strategy signal produced by the write strategy circuit; a circuit board having the digital signal processor mounted thereon; differential transmission lines for transmitting the one or more differential signals, connecting the one or more differential transmission drivers and the one or more current sources of the laser diode driver to each other, and transmitting the write strategy signal; and a respective second resistor connected between the differential transmission lines for each of the one or more differential transmission drivers, wherein each second resistor is provided in the digital signal processor, wherein the differential transmission lines comprise a cable that is one of a flexible print cable (FPC) or a flexible flat cable (FFC) and in contact with a metal case of the optical disc drive, wherein a differential line impedance of the cable changes in response to a contacting state of the cable with the metal case changing due to repetitive use of the optical disc drive, wherein the optical disc drive includes a tray-withdrawing structure, wherein a resistance value of each second resistor is a predetermined value in a range of 80Ω to 500Ω, and wherein a resistance value of each first resistor is 100 Ω.