Methods, systems, and devices for delay adjustment circuits are described. Amplifiers (e.g., differential amplifiers) may act like variable capacitors (e.g., due to the Miller-effect) to control delays of signals between buffer (e.g., re-driver) stages. The gains of the amplifiers may be adjusted by adjusting the currents through the amplifiers, which may change the apparent capacitances seen by the signal line (due to the Miller-effect). The capacitance of each amplifier may be the intrinsic capacitance of input transistors that make up the amplifier, or may be a discrete capacitor. In some examples, two differential stages may be inserted on a four-phase clocking system (e.g., one on 0 and 180 phases, the other on 90 and 270 phases), and may be controlled differentially to control phase-to-phase delay.

A delay circuit includes the following: an input module, configured to receive a target input signal and output the target input signal to a first node, the target input signal being a rising edge signal or a falling edge signal of a pulse signal; an output module, configured to output a target output signal, the target output signal being a delayed signal of the target input signal; and a delay control module, connected to the input module through the first node, and connected to the output module through a second node. The delay control module includes at least one delay capacitor unit, and the delay control module is configured to control a connection between the at least one delay capacitor unit and the first node according to a rising edge delay duration or a falling edge delay duration.

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 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.

Embodiments herein relate to a clock interpolation system. The system may be configured to identify, at a change in logical state of a recovered clock signal, a logical state of a first signal when the first signal is delayed by a delay value. The system may be further configured to identify, at a change in logical state of a second signal, a logical state of the clock signal when the clock signal is delayed by the delay value. Based on the two identifications, the delay value and/or a timing of the clock signal may be adjusted. Other embodiments may be described and/or claimed.

Embodiments herein relate to a clock interpolation system. The system may be configured to identify, at a change in logical state of a recovered clock signal, a logical state of a first signal when the first signal is delayed by a delay value. The system may be further configured to identify, at a change in logical state of a second signal, a logical state of the clock signal when the clock signal is delayed by the delay value. Based on the two identifications, the delay value and/or a timing of the clock signal may be adjusted. Other embodiments may be described and/or claimed.

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 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.

There is provided an optical encoder including a phase shifter circuit, two multiplexers, two digital circuits and four comparators. The phase shifter circuit receives signals from an amplifier and outputs multiple phase shifted signals. Each of the two multiplexers receives a half of the multiple phase shifted signals and outputs two pairs of phase shifted signals, each pair having 180 degrees phase difference, respectively to two comparators connected thereto. Each of the two digital circuits controls the corresponding multiplexer to select the two pairs of phase shifted signals from the half of the multiple phase shifted signals.

There is provided an optical encoder including a phase shifter circuit, two multiplexers, two digital circuits and four comparators. The phase shifter circuit receives signals from an amplifier and outputs multiple phase shifted signals. Each of the two multiplexers receives a half of the multiple phase shifted signals and outputs two pairs of phase shifted signals, each pair having 180 degrees phase difference, respectively to two comparators connected thereto. Each of the two digital circuits controls the corresponding multiplexer to select the two pairs of phase shifted signals from the half of the multiple phase shifted signals.