Abstract: An interchannel skew adjustment circuit adjusts signal skew between a first channel and a second channel. The circuit includes a phase adjustment circuit configured to receive a signal of the first channel, delay the signal by a discretely variable delay amount, and output a delayed signal; a channel coupling circuit configured to receive the signal output from the phase adjustment circuit and a signal of the second channel, and detect a phase difference between these two signals; and a controller configured to control the delay amount in the phase adjustment circuit based on a result detected by the channel coupling circuit. This interchannel skew adjustment circuit adjusts the interchannel signal skew only at a sender or a receiver, thereby reducing the circuit area and the power consumption.

Abstract: An interchannel skew adjustment circuit adjusts signal skew between a first channel and a second channel. The circuit includes a phase adjustment circuit configured to receive a signal of the first channel, delay the signal by a discretely variable delay amount, and output a delayed signal; a channel coupling circuit configured to receive the signal output from the phase adjustment circuit and a signal of the second channel, and detect a phase difference between these two signals; and a controller configured to control the delay amount in the phase adjustment circuit based on a result detected by the channel coupling circuit. This interchannel skew adjustment circuit adjusts the interchannel signal skew only at a sender or a receiver, thereby reducing the circuit area and the power consumption.

Abstract: In performing calibration, a control circuit in a calibration circuit of an interface circuit controls a selector so that voltages V1, VREF or voltages V1, V2 are applied to a comparator. The two voltages input to the comparator is switched between positive and negative inputs of the comparator. In both of the states, the control circuit obtains signal values of variable-resistor control signals UPCODE, DNCODE at a time when an output of the comparator is changed, and obtains calibration data to control the resistance value of the terminating resistor by using a mean value of the obtained signal values.

Abstract: The present disclosure improves tracking characteristics of an envelope detected from an input signal to the input signal. A detector, which obtains an output signal from an input signal containing a target signal, and outputs the output signal, includes: a comparator configured to compare the input signal to the output signal, and output an obtained comparison result; and an envelope generator configured to weight a first value and a second value having a sign opposite to that of the first value in accordance with the comparison result, integrate the weighted first value and the weighted second value, and output an integral value as the output signal. The envelope generator includes a first gain generator configured to output the first value in accordance with an amplitude of the input signal.

Abstract: A detector obtains an output signal from an input signal containing a target signal and outputs the output signal. The detector includes an amplifier configured to receive the input signal and the output signal, compare the input signal to the output signal to output a comparison result; an envelope generator configured to weight a first value and a second value having a sign opposite to that of the first value in accordance with the comparison result, integrate the weighted first value and the weighted second value, and output an integration result as the output signal; and a controller configured to control the envelope generator in accordance with the input signal. The controller controls the envelope generator to mitigate an increase in an absolute value of the integration result when the input signal contains a frequency component other than a frequency component of the target signal.

Abstract: An information recording system for recording information on an optical disc using a reference clock signal generated based on a push-pull signal including a wobble frequency component, the system includes an amplitude obtaining unit for obtaining an amplitude value of the push-pull signal, a threshold calculation unit for calculating a displacement threshold of the push-pull signal based on the amplitude value obtained by the amplitude obtaining unit, and a noise reduction unit for generating a corrected push-pull signal by correcting the push-pull signal such that a displacement exceeding the displacement threshold is reduced. The reference clock signal is generated based on the corrected push-pull signal generated by the noise reduction unit.

Abstract: An information recording system for recording information on an optical disc using a reference clock signal generated based on a push-pull signal including a wobble frequency component, the system includes an amplitude obtaining unit for obtaining an amplitude value of the push-pull signal, a threshold calculation unit for calculating a displacement threshold of the push-pull signal based on the amplitude value obtained by the amplitude obtaining unit, and a noise reduction unit for generating a corrected push-pull signal by correcting the push-pull signal such that a displacement exceeding the displacement threshold is reduced. The reference clock signal is generated based on the corrected push-pull signal generated by the noise reduction unit.