Transition state output device, time-to-digital converter and A / D conversion circuit

Abstract

To provide a transition state output device that can reduce a variation in time during which each internal state continues.SOLUTION: A transition state output device comprises: a ring-shaped oscillation circuit that starts oscillation based on a trigger signal; a state machine whose state changes according to a change in the state of the ring-shaped oscillation circuit; a transition state acquisition unit that, in synchronization with a reference signal, acquires and holds state information including a signal output from the ring-shaped oscillation circuit and a signal output from the state machine; and an internal state calculation unit that, based on the state information held by the transition state acquisition unit, calculates an internal state according to the frequency of the changes in the state of the ring-shaped oscillation circuit. The time from when a transition of the internal state is made from a first internal state to a second internal state until when a transition is made to the first internal state again is longer than the interval of time at which the state information held by the transition state acquisition unit is updated.SELECTED DRAWING: Figure 2

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