There is provided a signal interpolation device, including: a first amplifier to generate a first signal representing a difference between an input signal and a first reference voltage; a second amplifier to generate a second signal representing a difference between the input signal and a second reference voltage; a first output amplifier to amplify the first signal to generate a first output signal; a second output amplifier to amplify the second signal to generate a second output signal; a third output amplifier to amplify a sum of a first interpolation signal and the first signal to generate a third output signal, the first interpolation signal representing a voltage generated by dividing a difference between the first reference voltage and the second reference voltage by “2^n”; and a fourth output amplifier to amplify a difference between the second signal and the first interpolation signal to generate a fourth output signal.