ATR1842 Description
The ATR1842 is a front monitor diode (FMD) which controls the laser power of the optical pickup for Blu-ray/HD-DVD, DVD and CD drives in one IC. With the serial programming interface (SPI) it is possible to fit the laser power for Blu-ray/HD-DVD, DVD and CD. 2 bits are used to set the mode/gain level and 6 additional bits are used for gain trimming, within ±6 dB.