| 摘要 |
A circuit (13) for controlling the extinction ratio, a chip and an optical module (1), relating to the technical field of optical communications, used for improving control precision during the process of controlling a constant extinction ratio. The circuit (13) is applied to an optical module comprising a modulation current generation module (11) and a light emitting assembly (12). The circuit (13) comprises a modulation current control module (131). An input terminal of the modulation current control module (131) is connected to an output terminal of the light emitting assembly (12). An output terminal of the modulation current control module (131) is connected to a control terminal of the modulation current generation module (11). The modulation current control module (131) is used for utilizing current values respectively corresponding to the high level and low level of a backlight current output by the light emitting assembly (12) to control the amplitude of the modulation current generated by the modulation current generation module (11), so as to make the extinction ratio constant. |
