An interpolator includes a first delay circuit, a second delay circuit, and a tunable delay circuit. The first delay circuit delays a first input signal for a fixed delay time, so as generate a first output signal. The second delay circuit delays a second input signal for the fixed delay time, so as to generate a second output signal. The tunable delay circuit delays the first input signal for a tunable delay time, so as to generate an output interpolation signal. The tunable delay time is determined according to the first output signal, the second output signal, and the output interpolation signal.

An interpolator includes a first delay circuit, a second delay circuit, and a tunable delay circuit. The first delay circuit delays a first input signal for a fixed delay time, so as generate a first output signal. The second delay circuit delays a second input signal for the fixed delay time, so as to generate a second output signal. The tunable delay circuit delays the first input signal for a tunable delay time, so as to generate an output interpolation signal. The tunable delay time is determined according to the first output signal, the second output signal, and the output interpolation signal.

Disclosed herein is a programmable delay circuit for providing an adjustable delay for a signal transmitted from an input node to an output node. The adjustable delay circuit includes an input node; an output node; and a pair of inverter circuits coupled in series between the input node and the output node, wherein the pair of inverter circuits is configured to provide an adjustable delay for a signal transmitted from the input node to the output node. At least one inverter circuit of the pair of inverter circuits includes a state-programmable memory element that allows the pair of inverter circuits to be configurable between a first delay mode or a second delay mode.

Disclosed herein is a programmable delay circuit for providing an adjustable delay for a signal transmitted from an input node to an output node. The adjustable delay circuit includes an input node; an output node; and a pair of inverter circuits coupled in series between the input node and the output node, wherein the pair of inverter circuits is configured to provide an adjustable delay for a signal transmitted from the input node to the output node. At least one inverter circuit of the pair of inverter circuits includes a state-programmable memory element that allows the pair of inverter circuits to be configurable between a first delay mode or a second delay mode.

A digitally controlled delay line (DCDL) includes an input terminal, an output terminal, and a plurality of stages configured to propagate a signal along a first signal path from the input terminal to a selectable return stage of the plurality of stages, and along a second signal path from the return stage of the plurality of stages to the output terminal. Each stage of the plurality of stages includes a first inverter configured to selectively propagate the signal along the first signal path, a second inverter configured to selectively propagate the signal along the second signal path, and a third inverter configured to selectively propagate the signal from the first signal path to the second signal path. Each of the first and third inverters has a tunable selection configuration corresponding to greater than three output states.

A digitally controlled delay line (DCDL) includes an input terminal, an output terminal, and a plurality of stages configured to propagate a signal along a first signal path from the input terminal to a selectable return stage of the plurality of stages, and along a second signal path from the return stage of the plurality of stages to the output terminal. Each stage of the plurality of stages includes a first inverter configured to selectively propagate the signal along the first signal path, a second inverter configured to selectively propagate the signal along the second signal path, and a third inverter configured to selectively propagate the signal from the first signal path to the second signal path. Each of the first and third inverters has a tunable selection configuration corresponding to greater than three output states.

In certain aspects, a duty-cycle monitor includes a first oscillator, and a flop having a signal input, a clock input, and an output, wherein the signal input is coupled to an input of the duty-cycle monitor, and the clock input is coupled to the first oscillator. The duty-cycle monitor also includes a first counter having a count input, an enable input, and a count output, wherein the count input of the first counter is coupled to the first oscillator, and the enable input of the first counter is coupled to the output of the flop. The duty-cycle monitor also includes a second counter having a count input, an enable input, and a count output, wherein the count input of the second counter is coupled to the first oscillator, and the enable input of the second counter is coupled to the output of the flop.

In certain aspects, a duty-cycle monitor includes a first oscillator, and a flop having a signal input, a clock input, and an output, wherein the signal input is coupled to an input of the duty-cycle monitor, and the clock input is coupled to the first oscillator. The duty-cycle monitor also includes a first counter having a count input, an enable input, and a count output, wherein the count input of the first counter is coupled to the first oscillator, and the enable input of the first counter is coupled to the output of the flop. The duty-cycle monitor also includes a second counter having a count input, an enable input, and a count output, wherein the count input of the second counter is coupled to the first oscillator, and the enable input of the second counter is coupled to the output of the flop.

A system includes a first park circuit having a signal input, an output, and a control input. The system also includes a first signal path having an input and an output, wherein the input of the first signal path is coupled to the output of the first park circuit. The system also includes a second park circuit having a signal input, an output, and a control input, wherein the signal input of the second park circuit is coupled to the output of the first signal path. The system further includes a second signal path having an input and an output, wherein the input of the second signal path is coupled to the output of the second park circuit.

A system includes a first park circuit having a signal input, an output, and a control input. The system also includes a first signal path having an input and an output, wherein the input of the first signal path is coupled to the output of the first park circuit. The system also includes a second park circuit having a signal input, an output, and a control input, wherein the signal input of the second park circuit is coupled to the output of the first signal path. The system further includes a second signal path having an input and an output, wherein the input of the second signal path is coupled to the output of the second park circuit.