Time-to-Digital Converters and Time-to-Digital Conversion Methods for Higher Order Noise Shaping

摘要

PURPOSE: A time-to-digital converter and a time-to-digital converting method thereof are provided to enhance the resolution of the time-to-digital converter by performing the noise shaping of a high degree through an opening/closing type ring oscillator. CONSTITUTION: An enable signal generator(110) generates an enable signal enabled for the time interval from the rising edge of the first digital input signal to the rising edge of the second digital input signal. An opening/closing type ring oscillator generates an oscillation signal in response to the enable signal. A counter(130) generates a digital output signal corresponding to the number of rising edges of the oscillation signal in response to the oscillation signal. A time amplifier(340) generates the first time interval output signal and second time interval output signal with the time interval among the rising edges in response to the enable signal and oscillation signal.