In a time-to-digital conversion stage, a time-to-digital conversion circuit outputs an n-bit digital signal, which represents an integer value ranging from −(2n-1−1) to +(2n-1−1), based on a phase difference between a first and a second signals input thereto; a time difference amplifier circuit amplifies the phase difference between the first and the second signals 2n-1 times, and outputs two signals having an amplified phase difference therebetween; a delay adjustment circuit adds a phase difference dependent on the digital signal to the two signals output from the time difference amplifier circuit, and outputs another two signals; an output detection circuit detects that the delay adjustment circuit has output the another two signals, and outputs a detection signal; and a storage circuit latches the digital signal in synchronism with the detection signal. Multi-stage coupling of the time-to-digital conversion stages forms a pipeline time-to-digital converter.