1. Field
The following description relates to a photo detecting element, and an optical pick-up apparatus and an optical disc drive including the same, and more particularly, to a photo detecting element having an improved gain adjusting structure.
2. Description of Related Art
A photo detecting element, for example, a Photo Detector Integrated Circuit (PDIC) such as an optical monitoring detector used in an optical pick-up apparatus, is used to monitor the power of light output from a Laser Diode (LD) and typically includes a Photo Diode (PD) and an amplifier. A photo detecting element is typically included in an optical pick-up apparatus of an optical disk drive.
In an optical pick-up apparatus, when information is written on or read from a disc, the photo detecting element generates a monitoring output signal for power calibration and an auto power control signal for controlling light emitted by the LD towards the disc.
The photo detecting element is typically a semiconductor device into which various parts are integrated. An input signal includes a component such as an SDIO component and an SCLK component that acts as noise on a differential output signal. Typically, a port causing such noise is disposed close to a differential output port and causes the quality of an output signal to deteriorate. Alternatively, when a port to which a driving voltage Vcc is applied is disposed close to the differential output port, the LD may be damaged by an overcurrent caused by a short-circuit between the two ports.