Methods and devices for TDC resolution improvement

A time to digital converter (TDC) circuit configured to:

• receive a reference clock (REF) signal and a signal derived from a local oscillator (LO);
• generate a plurality of digital values based on one or more TDC measurements by a single TDC measurement component configured, wherein the plurality of digital values are indicative of a phase difference between the signal derived from the LO and the REF signal within a single REF cycle, wherein each of the plurality of digital values are determined from a separate series of TDC quantization levels;
• generate a combined series of quantization levels, wherein each quantization level of the combined series of quantization levels is a sum of simultaneously-in-time occurring ones of the separate series of TDC quantization levels;
• and
• determine a combined digital value from the combined series of TDC quantization levels and at least one of the plurality of digital values to generate an output of the TDC circuit.

A method for a time to digital converter (TDC) circuit to produce an output, the method comprising:

• receiving a reference clock (REF) signal and a signal derived from a local oscillator (LO);
• generating a plurality of digital values based on one or more TDC measurements by a single TDC measurement component configured, wherein the plurality of digital values are indicative of a measured phase difference between the signal derived from the LO and the REF signal, wherein each of the plurality of digital values are determined from a unique set of a plurality of sets of TDC measurement component quantization levels;
• generating a combined series of quantization levels based on a combination of the plurality of sets of TDC measurement component quantization levels;
• and
• determining a combined digital value from the combined series of quantization levels and at least one of the plurality of digital values to generate the output of the TDC circuit.