LIGHT EMITTING CIRCUIT FOR OPTICAL COMMUNICATION

摘要

PROBLEM TO BE SOLVED: To provide the light emitting circuit by monitoring a signal relating to transmission data used to drive an LED so as to avoid a lighting state resulting in a circuit damage or the like thereby avoiding a similarly state caused by trouble of a circuit component in use. SOLUTION: In the case that an output signal level of an integration circuit 2 reaches a level, over a prescribed level X decided by a comparator circuit 3 or over when a state of coded data from a data control section 1 is consecutively 'H' for a time or over (that is an error signal in the case of a Manchester code or the like), an output signal of the comparator circuit 3 goes to 'H' from the moment. An output signal level of a gate 4 detecting the H level from the comparator circuit 3 goes to '0' so that a drive control signal resulting from transmission data is not given to an LED drive circuit.