PULSE SIGNAL OUTPUT DEVICE

摘要

To reduce radiated noise in an outputted pulse signal. A pulse signal output device for outputting a pulse signal generated by a modulation means to the exterior, wherein the modulation means has: a computation circuit having in the interior a pull up resistance connected to the power supply; a versatile input/output terminal connected to the computation circuit; an input/output selection means for selecting whether to use the versatile input/output terminal for inputting or outputting; a pull up resistance connection means for connecting and disconnecting between the pull up resistance and the versatile input/output terminal; and a pull up resistance connection control circuit for performing control so as to actuate the pull up resistance connection means when the versatile input/output terminal is selected for inputting. When the output signal level of the pulse signal starts transition, the input/output selection means sets the versatile input/output terminal so as to be used for inputting. When the versatile input/output terminal is set so as to be used for inputting, the pull up resistance connection means connects the pull up resistance and the versatile input/output terminal to each other. After a given time has elapsed, the input/output selection means switches the versatile input/output terminal to an output terminal.