Patent ID: 8138843
Filing Date: 2012-03-20
Classification: G04F,H03K

Abstract:
1. A gated ring oscillator time-to-digital converter for modifying time-to-digital converter quantization noise, the gated ring oscillator time-to-digital converter comprising: a plurality of delay stages wherein each delay stage has an enable terminal, the enable terminal receives an enable signal that has two states, an enable state and a disable state, being coupled to said enable terminal of said delay stages, the enable signal having a pulse with a duration substantially equal to a time period to be measured, each delay stage having multiple weighted delay elements and connection to said multiple delay elements are made to the outputs of said delay stages using a connection matrix in such a manner that reduces the delay for each delay stage, and a measurement module to determine a number of transitions of the delay stages, said delay stages being interconnected to allow sustained transitions to propagate through the delay stages when said enable signal is in the enable state, and preservation of a state of the gated ring oscillator when said enable signal is in the disable state allowing the phase of the gated ring oscillator to be preserved and phase integration to resume when the enable signal is asserted, thus holding the state of the gated ring oscillator during the disable state allowing the measurement module to start another measurement using the state of the gated ring oscillator from a previous measurement, wherein the state represents a voltage on a capacitance of the delay stage.