Oscillation circuit and semiconductor device

Abstract

The present invention provides an oscillation circuit and a semiconductor device that can cope with a wide range of operating power supply voltages with a simple circuit structure. The oscillation circuit includes a ring oscillator and a waveform shape circuit configured to shape a waveform of an output signal of the ring oscillator. The waveform shape circuit includes: a preamplifier circuit configured to supply a first signal and a second signal which have the same frequency as a frequency of the output signal, the first signal having an opposite phase from a phase of the output signal, the second signal having an opposite phase from the phase of the first signal; and an amplitude amplifier circuit including a first transistor, a second transistor, a third transistor including a drain connected to a drain of the first transistor and a gate connected to a drain of the second transistor, and a fourth transistor including a drain connected to the drain of the second transistor and a gate connected to the drain of the first transistor.

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