AK2570 is the monolithic CMOS LSI has the function of ‘Feed Forward Automatic Power Control (APC)’ for the
Laser Diode (LD) module and maintains the emission intensity of the LD module constant with the high accuracy.
For stabilizing the emission intensity of the LD module affected by the ambient temperature, AK2570 feeds the
compensation voltage from the 2channels - 8bits D to A converter to control the Bias- and the Modulation- current
for the LD module. The compensation voltage corresponds to the temperature characteristic data of the LD module
retained in the on-chip EEPROM and the ambient temperature detected by the on-chip thermo-sensor.
AK2570 outputs the alarm signal for the weakened LD emission caused by the aging degradation with comparing
the alarm threshold level and the signal from the monitoring Photo Diode (PD).
The data of the compensation voltage and the alarm threshold level retained in the on-chip EEPROM can be set to
suit for the characteristics of each LD module.