OPTICAL TRANSMITTER WITH THE FUNCTION OF AUTOMATIC TEMPERATURE COMPENSATION

摘要

An optical transmitter having a function of automatically compensating temperature is provided to support not only burst mode optical communication, needing fast operation speed, but also continuous signal mode optical communication by performing the control by digital sampling. An optical transmitter having a function of automatically compensating temperature comprises the followings: a laser diode(302) outputting an optical signal; a laser driving circuit(300) controlling the optical signal output of the laser diode according to input data; a photo diode(304) outputting a current signal corresponding to the optical signal output of the laser diode; a low pass filter(306) outputting the current signal according to the average level of the current signal outputted from the photo diode; a preamplifier(308) which converts the current signal outputted from the low pass filter into a voltage signal and outputs it; and a digital control part(310) which calculates the difference between a preset reference voltage and the signal level of the voltage signal outputted from the preamplifier, and generates a control signal for controlling a bias current source of the laser driving circuit which provides a bias current to the laser diode according to the calculated difference.