Apparatus and methods for clock duty cycle correction and deskew are provided. In certain embodiments, a clock distribution circuit includes a clock driver that provides a differential clock signal to a clock slicer over a pair of transmission lines. The clock distribution circuit further includes a resistor-inductor-capacitor (RLC) tuning circuit for providing termination between the pair of transmission lines and a differential input to the clock slicer. The RLC tuning circuit includes a pair of resistor digital-to-analog converters (resistor DACs or RDACs) coupled to the pair of transmission lines and a pair of controllable inductor-capacitor (LC) circuits coupled to the pair of transmission lines.

A driver circuit drives an output terminal with an input/output voltage using an NMOS transistor and a PMOS transistor. A pre-driver for the NMOS transistor supplied with a drive voltage and receives a data signal referenced to the drive voltage. A pre-driver for the PMOS transistor has a positive supply input connected to the positive supply rail, a negative supply input receiving a second drive voltage equal to the supply voltage minus the drive voltage. A level shifter circuit, shifts the data signal to be referenced between the supply voltage and the second drive voltage. A charge pump circuit for providing second drive voltage, the charge pump circuit driven with a variable switching frequency proportional to a current of the PMOS transistor.

A staggering signal generation circuit includes a pulse generation circuit, a counting circuit and a signal generation circuit. The pulse generation circuit generates a first periodic pulse signal and a second periodic pulse signal; the counting circuit counts the first periodic pulse signal and the second periodic pulse signal to generate rising edge triggering signals and falling edge triggering signals; and the signal generation circuit generate a staggering pulse signal according to the input rising edge triggering signals and the input falling edge triggering signals.

Provided are a summing circuit and an equalizer including the summing circuit. The summing circuit includes: a reference signal generator generating a first reference signal and a second reference signal, based on a coefficient code; a first non-overlap clock buffer generating a first switching signal and a second switching signal by using the first reference signal; and a first current source receiving the first switching signal and the second switching signal generated by the first non-overlap clock buffer, generating a first output current by using a bias voltage, and outputting the first output current to an output line, wherein the first switching signal includes a switching signal and a complementary switching signal that is a complementary signal to the switching signal, and wherein a logic low period of the second switching signal is included in a logic high period of the complementary switching signal of the first switching signal.

A driver circuit drives an output terminal with an input/output voltage using an NMOS transistor and a PMOS transistor. A pre-driver for the NMOS transistor supplied with a drive voltage and receives a data signal referenced to the drive voltage. A pre-driver for the PMOS transistor has a positive supply input connected to the positive supply rail, a negative supply input receiving a second drive voltage equal to the supply voltage minus the drive voltage. A level shifter circuit, shifts the data signal to be referenced between the supply voltage and the second drive voltage. A charge pump circuit for providing second drive voltage, the charge pump circuit driven with a variable switching frequency proportional to a current of the PMOS transistor.

An adding circuit for multi-channel signals and an implementation method thereof are disclosed. The adding circuit for multi-channel signals includes an operational amplifier, a plurality of charge and discharge circuits, a charge transfer circuit, a switch sequence and a control circuit. In this disclosure, the duty cycle of each charge and discharge circuit and the charge transfer circuit can be programmed and preset according to the actual needs, which is not only suitable for the static voltage adding circuit, but also suitable for the dynamic voltage adding circuit. When there are multi-channel signals, the output interference caused by individual signals can be prevented. The area of the adding circuit can be greatly reduced. The adding circuit can be IP-based, controlled by programing and presetting a variety of combined adding algorithms, so the chip cost can be saved and a wide applicability in detection and monitoring can be provided.

A differential signal receiver is provided. The differential signal receiver includes a first differential difference amplifier, a second differential difference amplifier, a latch and a first inverter. The first differential difference amplifier and the second differential difference amplifier compare a voltage value of an input signal with a first threshold value and a second threshold value, respectively, so as to output a first difference signal and a second difference signal, respectively. The second threshold value is an opposite value of the first threshold value. The latch has a set terminal for receiving the first difference signal and a reset terminal for receiving the second difference signal. The first inverter is configured to receive the first latch signal and output the first output signal. The first output signal has a duty cycle being the same as a duty cycle of the input signal.

In a dead time adjusting circuit, a switch voltage appearing at a connection node between a first output switch and a second output switch, which are connected in series between two different potentials, is monitored to detect a first dead time, which is from a time at which the second output switch is turned off to a time at which the first output switch is turned on, and a second dead time, which is from a time at which the first output switch is turned off to a time at which the second output switch is turned on, each of the first and second dead times being feedback-controlled to be identical to a predetermined target value.

A clock generation circuit coupled to an integrator circuit uses a variable resistance that is adjusted in a transconductance bias feedback circuit. This resistance is calibrated to the reciprocal of the transconductance of the input amplifier. The product of the adjusted resistance and a capacitance in the clock generation circuit provides a time constant for the settling time of the integrator and controls a pulse width of an adaptively controlled duty cycle output clock.

A clock generation circuit includes a two-phase non-overlapping clock generation circuit, an inverter, and a delay circuit. The two-phase non-overlapping clock generation circuit is configured to generate a first phase clock signal and a second phase clock signal based on a non-inverted clock signal and an inverted clock signal. The first phase clock signal and the second phase clock signal correspond to a same logical value during a first duration and a second duration within a clock cycle. The inverter is configured to generate the inverted clock signal based on an input clock signal. The delay circuit is configured to generate the non-inverted clock signal based on the input clock signal. The delay circuit has a predetermined delay sufficient to cause a difference between the first duration and the second duration to be less than a predetermined tolerance.