Preamplifier circuit, clock switching circuit, and optical receiver

摘要

A preamplifier circuit, a clock switching circuit, and an optical receiver are provided that include a preamplifier that controls a bandwidth for conducting amplification on an input signal by varying a feedback resistance according to a control signal; a control signal generating part that determines the band of the output signal of the preamplifier to generate the control signal; and a correction signal generating part that generates a correction signal for correcting the control signal; wherein the correction signal corrects the control signal to adjust the feedback resistance. Accordingly, even when the number of rises and falls of an optical input signal in a given time period is less than a predetermined number range, the control signal may be properly generated to successfully conduct band control. Thus, an optical receiver that is not dedicated to a predetermined input signal pattern but is rather capable of automatically adjusting its bandwidth may be realized, and the cost of manufacturing the optical receiver structure may be reduced.