Jitter sensor circuit

A method, comprising:

• generating, by a reference circuit, a reference voltage using a power supply voltage;
• generating, by a time-to-voltage converter circuit in response to being activated, a sample signal using the reference voltage, wherein a first voltage level of the sample signal is proportional to a period of time a clock signal is at a particular logic value;
• activating, by a control circuit, the time-to-voltage converter circuit at a plurality of time points;
• and
• generating, by an analog-to-digital converter circuit using the reference voltage, an output signal based on the sample signal, wherein the output signal includes a plurality of bits whose value is indicative of the period of time the clock signal is the particular logic value.

An apparatus, comprising:

• a clock generation circuit configured to generate a clock signal;
• a plurality of circuit blocks configured to receive the clock signal;
• and
• a jitter sensor circuit configured to:
• generate a reference voltage using a power supply voltage;
• generate, at random time points, a sample signal using the reference voltage, wherein a first voltage level of the sample signal is proportional to a period of time the clock signal is at a particular logic value;
• and
• generate an output signal based on the sample signal, wherein the output signal includes a plurality of bits whose value is indicative of the period of time the clock signal is the particular logic value.