A delay cell includes a cascode transistor and an inverter. The cascode transistor is used to receive a control voltage to generate a bias current, and includes a source terminal, a drain terminal, and a gate terminal receiving the control voltage. The inverter is coupled to the cascode transistor and used to generate an output signal according to the bias current in response to an input signal.

A delay cell includes first and second delay elements coupled in series between an input terminal and an output terminal, and a switch having one terminal coupled to a common node of the first and second delay elements, and another terminal that is floating, and turned on according to a delay control signal.

In described examples of an integrated circuit (IC), an oscillator includes Schmitt trigger delay cells connected in a ring topology. The Schmitt trigger delay cells have a high input threshold approximately equal to Vdd and a low input threshold approximately equal to Vss to increase delay through each cell. An output buffer receives a phase signal from an output terminal of one of the Schmitt trigger delay cells and converts a transition phase signal to a faster transition clock signal. The output buffer has control circuitry that generates non-overlapping control signals in response to the phase signal, to control an output stage to generate the fast transition clock signal while preventing short circuit current in the output stage.

Delay circuit includes: first to fourth transistors; capacitor; constant current source; and resistor. The first transistor has a gate connected to an input terminal, a source connected to the first power supply terminal, and a drain. The second transistor has a gate connected to an input terminal and the gate of the first transistor, a drain connected to the drain of the first transistor and the second terminal of the capacitor, and a source. The third transistor has a gate connected to a node between the drain of the first transistor, the drain of the second transistor, and the second terminal of the capacitor, a source connected to the second power supply terminal, and a drain. The fourth transistor has a gate connected to the node and the gate of the third transistor, a drain connected to the drain of the third transistor and an output terminal, and a source.

A clock driver circuit for low powered clock driving may include: a multiple phase divider; a buffer supplying at least one of multiple phases to the multiple phase divider at a center frequency that is an integer multiple of an input frequency; and wherein the multiple phase divider and the buffer share a same current from a supply rail.

A clockless delay adaptation loop configured to adapt to random data includes a first and a second delay line, an autocorrelator, and a controller. The autocorrelator receives an input signal for the delay adaptation loop and the output from the first delay line, and includes a first logic circuit configured to output a first autocorrelation and a second logic circuit configured to output a second autocorrelation. The controller is configured generate a control signal for one of the first and second delay lines based on the first and second autocorrelations. In some examples, the first logic circuit is an XNOR gate, and the second logic circuit is an OR gate. In some examples, the OR gate can have a gain that is two times a gain of the XNOR gate. In some examples, an amplifier having two times the gain of the XNOR gate is coupled to the OR gate.

A delay line structure and a delay jitter correction method thereof are provided. The delay line structure comprises N delay units and N selectors. An output end of the N−1th delay unit is connected to a first input end of the N−1th selector and an input end of the Nth delay unit respectively, the N−1th selector inputs the N−1th selection signal, an output end of the Nth delay unit is connected to a first input end of the Nth selector, an output end of the Nth selector is connected to a second input end of the N−1th selector, and the Nth selector inputs the Nth selection signal. The time delay units and the selectors are stacked forwards according to the above-mentioned rule until the input ends of the first time delay units are connected with input signals and the output ends of the first selectors are connected with output signals.

In described examples of an integrated circuit (IC), an oscillator includes Schmitt trigger delay cells connected in a ring topology. The Schmitt trigger delay cells have a high input threshold approximately equal to Vdd and a low input threshold approximately equal to Vss to increase delay through each cell. An output buffer receives a phase signal from an output terminal of one of the Schmitt trigger delay cells and converts a transition phase signal to a faster transition clock signal. The output buffer has control circuitry that generates non-overlapping control signals in response to the phase signal, to control an output stage to generate the fast transition clock signal while preventing short circuit current in the output stage.

A delay circuit and a delay structure are provided. The circuit includes: a first delay unit configured to delay a rising edge and/or a falling edge of a pulse signal, where, an input terminal of the first delay unit receives the pulse signal, and an output terminal of the first delay unit outputs a first delay signal, and a second delay unit, configured to delay the first delay signal, where an input terminal of the second delay unit is connected to the output terminal of the first delay unit, and an output terminal of the second delay unit outputs a second delay signal.

A delay element including a first set of field effect transistors (FETs) with gates configured to receive a first control voltage; a second set of FETs coupled in series with the first set of FETs between a first voltage rail and a first node, respectively, the second set of FETs include gates configured to receive a set of complementary select signals, respectively; a third set of FETs including gates configured to receive a set of non-complementary select signals, respectively; a fourth set of FETs coupled in series with the third set of FETs between a second node and a second voltage rail, respectively, the fourth set of FETs including gates configured to receive a second control voltage; and an inverter coupled between the first node and the second node, the inverter including an input configured to receive an input signal and an output configured to produce an output signal.