Signal output circuit

A signal output circuit comprising:

• an inverting amplifier circuit including an input terminal and an output terminal, the inverting amplifier circuit configured to execute an inverting amplification operation based on an input signal to output a signal to the output terminal at a pull-up state, the inverting amplifier circuit having an output stage being either an open collector or an open drain;
• a feedback capacitor connected between the input terminal and the output terminal of the inverting amplifier circuit;
• a low pass filter circuit having an input and an output, the input being connected to the output terminal of the inverting amplifier, the output being connected to the feedback capacitor;
• an output transistor connected between the output terminal of the inverting amplifier circuit and a ground;
• a charge/discharge circuit connected to the input terminal of the inverting amplifier circuit, the charge/discharge circuit configured to
• charge the feedback capacitor in response to that the input signal is changed to a high level from a low level, and
• discharge the feedback capacitor in response to that the input signal is changed to the low level from the high level;
• and
• a clamping transistor connected between a conductive control terminal of the output transistor and the ground,
• wherein a conductive control terminal of the clamping transistor is connected to a connection terminal of the feedback capacitor and a connection terminal of the charge/discharge circuit, and
• wherein the clamping transistor conducts in response to that noise is applied to the conductive control terminal of the output transistor, in a situation where the feedback capacitor is discharged.