A time delay circuit comprising a plurality of differential delay cells each having a respective time delay and being arranged in series. Each delay cell comprises first and second inverter sub-cells, each comprising a respective PMOS transistor and an NMOS transistor arranged in series such that their respective drain terminals are connected at a drain node. Each of the transistors has a back-gate terminal and is arranged such that a respective voltage applied to said back-gate terminal linearly controls its respective threshold voltage. The back-gate terminal of the PMOS transistor in each inverter sub-cell is connected to the drain node of the other sub-cell and/or the back-gate terminal of the NMOS transistor in each inverter sub-cell is connected to the drain node of the other sub-cell. A control signal varies the time delay of the delay cell by adjusting a voltage supplied to a back-gate terminal of a transistor.

An analog to digital converter (ADC) comprising: a delay circuit having a complementary signal output; a first comparator having an input coupled to the complementary signal output of the delay circuit, the first comparator having a first output and a second output; a first dummy comparator having a first dummy input coupled to the first output and a second dummy input coupled to the second output, the first dummy comparator having a dummy output; a first interpolation comparator having an interpolation output and a first interpolation input coupled to the first output; a second dummy comparator having an input coupled to the interpolation output; and a second interpolation comparator having a second interpolation input and a third interpolation input, the second interpolation input coupled to the interpolation output and the third interpolation input coupled to the dummy output.

An analog to digital converter (ADC) comprising: a delay circuit having a complementary signal output; a first comparator having an input coupled to the complementary signal output of the delay circuit, the first comparator having a first output and a second output; a first dummy comparator having a first dummy input coupled to the first output and a second dummy input coupled to the second output, the first dummy comparator having a dummy output; a first interpolation comparator having an interpolation output and a first interpolation input coupled to the first output; a second dummy comparator having an input coupled to the interpolation output; and a second interpolation comparator having a second interpolation input and a third interpolation input, the second interpolation input coupled to the interpolation output and the third interpolation input coupled to the dummy output.

A comparator includes a pair of back-to-back negative-AND (NAND) gates and a delay circuit coupled to the pair of back-to-back NAND gates. The delay circuit is configured to modulate a triggering clock signal by an input voltage to generate a delayed clock signal with a delay that is based on the input voltage. Each of the pair of back-to-back NAND gates is configured to receive the delayed clock signal and generate a comparator output signal based on the delayed clock signal.

An adaptive feedback method for use in a memory device is provided. The memory device includes a first input-receiver circuit and a plurality of second input-receiver circuits. The method includes the steps of: providing a clock signal and an inverted clock signal to the first input-receiver circuit; generating an enable control signal by the first input-receiver circuit to control a first feedback path in the first input-receiver circuit; in response to the frequency of the clock signal and the inverted clock signal being higher than or equal to a predetermined frequency, activating the first feedback path in the first input-receiver circuit according to the enable control signal; and in response to the frequency of the clock signal and the inverted clock signal being lower than the predetermined frequency, deactivating the first feedback path in the first input-receiver circuit according to the enable control signal.

An adaptive feedback method for use in a memory device is provided. The memory device includes a first input-receiver circuit and a plurality of second input-receiver circuits. The method includes the steps of: providing a clock signal and an inverted clock signal to the first input-receiver circuit; generating an enable control signal by the first input-receiver circuit to control a first feedback path in the first input-receiver circuit; in response to the frequency of the clock signal and the inverted clock signal being higher than or equal to a predetermined frequency, activating the first feedback path in the first input-receiver circuit according to the enable control signal; and in response to the frequency of the clock signal and the inverted clock signal being lower than the predetermined frequency, deactivating the first feedback path in the first input-receiver circuit according to the enable control signal.

Clock distribution circuitry comprising: a plurality of first buffers and second buffers, the first and second buffers being inverting buffers; and control circuitry configured to generate first, second, third and fourth control signals for bulk-voltage control of transistors of the buffers, the control circuitry configured to control at least one of the first to fourth control signals as a variable signal.

Clock distribution circuitry comprising: a plurality of first buffers and second buffers, the first and second buffers being inverting buffers; and control circuitry configured to generate first, second, third and fourth control signals for bulk-voltage control of transistors of the buffers, the control circuitry configured to control at least one of the first to fourth control signals as a variable signal.

A comparator includes a pair of back-to-back negative-AND (NAND) gates and a delay circuit coupled to the pair of back-to-back NAND gates. The delay circuit is configured to modulate a triggering clock signal by an input voltage to generate a delayed clock signal with a delay that is based on the input voltage. Each of the pair of back-to-back NAND gates is configured to receive the delayed clock signal and generate a comparator output signal based on the delayed clock signal.

A comparator includes a pair of back-to-back negative-AND (NAND) gates and a delay circuit coupled to the pair of back-to-back NAND gates. The delay circuit is configured to modulate a triggering clock signal by an input voltage to generate a delayed clock signal with a delay that is based on the input voltage. Each of the pair of back-to-back NAND gates is configured to receive the delayed clock signal and generate a comparator output signal based on the delayed clock signal.