A duty adjustment circuit, and a delay locked loop circuit and a semiconductor memory device including the same are provided. The duty adjustment circuit includes a pulse generator configured to generate a pulse signal at a constant pulse width regardless of a frequency of a reference clock signal, based on frequency information, a code generator configured to generate a first predetermined number of delayed pulse signals by delaying the pulse signal, as a first code in response to the pulse signal, and a duty adjuster configured to receive a delay clock signal, and generate a duty correction clock signal by adjusting a slope of rising transition and a slope of falling transition of the delay clock signal in response to the first code and a second code.

A semiconductor memory device is provided. The semiconductor includes a data clock buffer that receives a data clock signal from a memory controller and outputs a pair of differential input signals, an edge delay controller that adjusts duty ratios of the pair of differential input signals based on a control code and outputs a pair of corrected clock signals, a first unit delay path circuit that generates four output clock signals having different phases based on the pair of corrected clock signals, a rising edge multiplexer that serially outputs data corresponding to a rising edge of each of the four output clock signals, a second unit delay path circuit that generates four duplicate clock signals having different phases based on the pair of corrected clock signals and a quadrature error correction circuit detector that detects a duty error based on the duplicate clock signals and outputs the control code.

A quadrature error correction circuit includes a duty cycle adjusting circuit, a phase interpolator, a phase detector, and a delay control circuit. The duty cycle adjusting circuit generates a first corrected clock signal and a second corrected clock signal whose skew and duty cycle error are concurrently adjusted by adjusting a delay of edges of a second clock signal and adjusting a delay of a falling edge of a first clock signal based on first through fourth control code sets. The phase interpolator generates a second delayed and selected clock signal by delaying a second selected clock signal selected from first through fourth adjusted clock signals. A phase detector detects a phase difference between a first selected clock signal and the second delayed and selected clock signal to generate an up/down signal. The delay control circuit generates the first through fourth control code sets based on the up/down signal.

A duty point detection circuit receiving an input signal and generating an output signal includes a charge pump receiving the input signal and the output signal and generating a comparison target signal from the input signal and the output signal, a magnitude of the comparison target signal being determined based on a first duty ratio of the input signal and a second duty ratio of the output signal, a comparator receiving a reference signal and the comparison target signal, and comparing the reference signal and the comparison target signal to generate a comparison result signal, and a control circuit receiving the input signal and the comparison result signal and adjusting the second duty ratio of the output signal to a constant duty ratio in successive cycle periods of the input signal.

Example embodiments of systems, methods, and computer-accessible mediums for identity verification and transaction authentication are provided. An exemplary system can comprise an application, a user device, and a server. The application can prompt a removal of a card chip, prompt an insertion of the card chip into the user device, determine an orientation of the card chip after the insertion of the card chip into the user device, and transmit, to the card chip, a first message. The card chip can encrypt the first message via one or more authentication protocols to generate an encrypted first message, transmit, to the server, the encrypted first message. The server can decrypt the encrypted first message, verify the decrypted first message, and transmit a second message to the application, wherein the application is configured to display a verification notification in response to the second message.

Example embodiments of systems, methods, and computer-accessible mediums for identity verification and transaction authentication are provided. An exemplary system can comprise an application, a user device, and a server. The application can prompt a removal of a card chip, prompt an insertion of the card chip into the user device, determine an orientation of the card chip after the insertion of the card chip into the user device, and transmit, to the card chip, a first message. The card chip can encrypt the first message via one or more authentication protocols to generate an encrypted first message, transmit, to the server, the encrypted first message. The server can decrypt the encrypted first message, verify the decrypted first message, and transmit a second message to the application, wherein the application is configured to display a verification notification in response to the second message.

Apparatuses and methods for setting a duty cycler adjuster for improving clock duty cycle are disclosed. The duty cycle adjuster may be adjusted by different amounts, at least one smaller than another. Determining when to use the smaller adjustment may be based on duty cycle results. A duty cycle monitor may have an offset. A duty cycle code for the duty cycle adjuster may be set to an intermediate value of a duty cycle monitor offset. The duty cycle monitor offset may be determined by identifying duty cycle codes for an upper and for a lower boundary of the duty cycle monitor offset.

Digital to analog converter generates an analog output corresponding to a digital input by controlling DAC cells using bits of the digital input. The DAC cells individually make a contribution to the analog output. Due to process, voltage, and temperature variations, the DAC cells may have duty cycle error or mismatches. To compensate for the duty cycle error of a DAC cell, a small amount of charge is injected into a low-impedance node of a DAC cell when the data signal driving the DAC cell transitions, or changes state. The small amount of charge is generated using a capacitive T-network, and the polarity of the charge injected is opposite of the error charge caused by duty cycle error. The opposite amount of charge thus compensates or cancels out the duty cycle error, and duty cycle error present at the output of the DAC cell is reduced.

Duty cycle adjustment circuitry includes a first stage, a second stage, and decoder circuitry. The first stage includes a first strength tuning circuit having first inverter branches, and a first fine tuning circuit having second inverter branches. The first strength tuning circuit and the first fine tuning circuit are coupled in parallel. The second stage includes a second strength tuning circuit having third inverter branches, and a second fine tuning circuit having fourth inverter branches. The second strength tuning circuit and the second fine tuning circuit are coupled in parallel. Further, the second stage is electrically coupled to the first stage. The decoder circuitry is electrically coupled to the first stage and the second stage. The decoder circuitry controls the first strength tuning circuit independently from the first fine tuning circuit to adjust the duty cycle of an input signal received by the duty cycle adjustment circuitry.

A circuit includes first and second transistors, a capacitor, and a controller. The controller is coupled to the control inputs of the first and second transistors. The controller configured to, during a first mode and in accordance with a first time-varying duty cycle, turn on and off the first transistor while turning on the second transistor when the first transistor is off. The controller is also configured to, during a second mode following the first mode, and in accordance with a second time-varying duty cycle, turn on and off the first transistor while turning on the second transistor when the first transistor is off.