To provide a PWM output circuit ensuring high precision control without generating jitter on the PWM output signal waveform with small circuit scale and inexpensively.

The PWM output circuit comprises a counter, a period storing section, a period detecting section, a pulse width storing section, a pulse width detecting section, an extra pulse storing section, a voltage generating section, a selector 110, and a voltage control section. Based on a period detection signal from the period detecting section, a pulse width detection signal from the pulse width detecting section, and a set value indicative of the first voltage of a first extra pulse from an extra pulse register 109, the voltage control section controls the selector 110 such that the first extra pulse follows to the pulse width and determines the output voltage from the PWM output circuit and its period.

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