Electronic device for converting input signal into digital value and method of operating same

An electronic device converting an input signal into a digital value and a method of operating the same are provided. The electronic device may include an analog-to-digital converter circuit that converts a level of an input signal to a digital input value in response to a clock signal; the oscillator is used for generating the clock signal; a first equalization circuit that generates a digital output signal by equalizing the digital input value; a first phase detector circuit detecting a phase of the digital output signal and generating a digital phase value; a loop filter generating a first digital output value based on the digital phase value; a second equalization circuit that generates a digital intermediate value by equalizing the digital input value; and a second phase detector circuit that detects a phase of the digital intermediate value and generates a second digital output value. The oscillator may adjust a frequency of the clock signal based on the first digital output value and the second digital