Samsung Electronics Co., Ltd.

Chang-sik Yoo

Won-chan Kim

Kee-wook Jung

Kye-hyun Kyung

Tae-Sung Jung

Jin-Soo Park

Young-Don Choi

Byung-se So

Young-eil Kim

Sang-bo Lee

Heung-Bae Lee

Hong-il Yoon

Yeon-jae Jung

Jae-woo Park

Yi-do Koo

Joon-young Park

A communication apparatus and a low noise amplifying method. The communication apparatus includes a gain adjusting unit to adjust a gain of an input signal; a combiner to generate an output signal using the signal gain-adjusted at the gain adjusting unit; and a feedback unit which provides a feedback signal, which is generated using the output signal generated at the combiner, to an input stage. Accordingly, various frequency bands defined in the wireless standards can be supported. Since the load impedance is generated without resistance, the manufacturing cost and the product size can be reduced.

Communication apparatus and low noise amplifying method

A memory system having a stub-bus configuration transmits a free-running clock through the same path as data signals. A single clock domain is employed for both read and write operations. For both operations, the read or write clock signal is routed through the same transmission path as the data, thereby increasing system transfer rates by maximizing the window of data validity. In this manner, data bus utilization is increased due to the elimination of a need for a preamble interval for the strobe signal, and pin count on the memory module connectors is therefore reduced.

Memory system having stub bus configuration

A clocking system and method in a point-to-point bus configuration overcomes the limitations of conventional approaches. In one embodiment, the present invention ensures the same phase relationship for the write clock in the write direction for all data transfers between modules, and similarly the same phase relationship for the read clock in the read direction for all data transfers between modules, regardless of module location. In another embodiment, on a given module, all transfers of data between a data buffer and a memory device in both read and write directions are clocked by a read clock signal and a write clock signal that have the same phase relationship and have the same propagation delay as the data bus between the buffer and the memory device.

Memory system having point-to-point bus configuration

An integrated circuit memory device for use in a memory system receives predetermined command/address signals from a memory controller and reads and writes data in response to the command/address signals. The memory device includes at least one input/output terminal that inputs/outputs data from/to the memory controller via a data input/output bus, at least one termination resistor, and an active termination control signal generator that generates a control signal to control active termination of the at least one data input/output terminal in response to a chip selection signal from the memory controller. The memory device also includes at least one switch coupled in series with the at least one termination resistor between the at least one input/output terminal and a predetermined voltage wherein the at least one switch is switched on/off in response to the control signal such that the at least one input/output terminal is connected/disconnected to/from the predetermined voltage responsive to the control signal and such that the at least one termination resistor is coupled in series between the predetermined voltage and the at least one input/output terminal when the at least one switch is switched on and such that the at least one input/output terminal is decoupled from the predetermined voltage when the at least one switch is switched off. Related memory systems and methods are also discussed.

Semiconductor memory systems, methods, and devices for controlling active termination

A phase detector system and method operate correctly, regardless of the point of time at which the operation of the delay locked loop is initialized with respect to the phases of reference and feedback clock signals. The system comprises a phase detector for a delay-locked loop for compensating for a difference in phase between a first clock signal and a second clock signal. The phase detector includes a first flip-flop receiving the first clock signal and generating a first output signal, the first flip-flop being reset by a first reset signal. A second flip-flop receives the reference clock signal and generates a second output signal, the second flip-flop being reset by a second reset signal, the first and second reset signals being sourced by separate logic paths. A reset circuit generates the first reset signal based on a combination of the first and second output signals and a first initialization signal, and generates the second reset signal based on a combination of the first and second output signals and a second initialization signal.

Apparatus for ensuring correct start-up and phase locking of delay locked loop

A delay locked loop which is capable of adjusting the number of delay devices in a delay line and controlling a phase increase or decrease more precisely than the adjustment by the number of delay devices and a phase control method thereof are provided. The delay locked loop includes a phase detector, a delay line, and a delay time adjuster. The phase detector compares the phase of a reference clock signal with the phase of a feedback clock signal and outputs the phase difference between the reference clock signal and the feedback clock signal as an error control signal. The delay line includes a plurality of first delay devices having a fixed delay time and connected in series. The number of first delay devices connected in series is adjusted in response to a shift signal. The delay line receives an input clock signal and outputs an output clock signal. The delay time adjuster controls a delay time in response to the reference clock signal and the error control signal generated from the phase detector, generates the input clock signal and adjusts the number of first delay devices.

Delay locked loop for controlling phase increase or decrease and phase control method thereof

A delay locked loop generates an advanced clock signal synchronized with a reference clock signal. The delay locked loop includes an input buffer, a variable delay circuit, a delay compensation circuit, a phase shifter, a delay controller, a phase sensing pump and a phase inversion controller. The variable delay circuit includes a multiplicity of delay terminals. The number of enabled delay terminals is controlled by a counting signal group. In the phase shifter, the phase of an output signal of the variable delay circuit generates the advanced clock signal with a phase of the reference clock signal. When the compared phase difference is more than &Pi;, the phase shifter inverts a delayed clock signal to generate the advanced clock signal. When the compared phase difference is less than &Pi;, the delayed clock signal is non-inverted to be generated as the advanced clock signal.

Delay locked loops and methods that shift the phase of a delayed clock signal based on a reference phase value

A semiconductor memory device and a system using the semiconductor memory device can perform a data sampling operation safely without a phase synchronization device such as delay locked loop (DLL) or phase locked loop (PLL), wherein the semiconductor memory device incorporates a strobe signal, which is synchronized with a data signal, both traversing similar-length paths between a memory device and a memory controller. In a read operation, the semiconductor memory device generates a first strobe signal synchronized with a read data signal, whereby a read data signal is outputted at both a rising and a falling edge of a strobe signal. In a write operation, a second strobe signal is generated whereby only a single edge is used to generate a write data signal, thereby allowing sufficient time for a data sampling operation to occur and thus operating at half the speed of a read operation.

Semiconductor memory device having different data rates in read operation and write operation

An output driver supplying constant output current regardless of output voltage changes. The output driver includes a current source for regulating changes in a voltage of an output terminal responsive to a reference signal, and an output current compensator that responds to the current source to supply constant current to the terminal. The current source includes a first MOS transistor having a drain coupled to the terminal and a gate to which the reference signal is input, and a second MOS transistor having a drain coupled to a source of the first MOS transistor, a gate to which data is input, and a source coupled to ground. The current source may be an open drain current source. The output current compensator includes a current compensator coupled to the terminal, and a sensing driver for sensing voltage changes of the terminal and driving the current compensator.

Output driver having output current compensation and method of compensating output current

A duty cycle correction circuit includes a duty cycle corrector and a detection circuit. The duty cycle corrector generates a first input signal having a second duty cycle with a higher degree of equivalence than the first duty cycle in response to a first detection signal and a first control signal having a first duty cycle. The detection circuit generates the first detection signal in response to the first input signal. The detection circuit includes a current source having first and second current sources and a bias circuit that is electrically coupled to the first and second current sources and controls a bias of the first and the second current sources responsive to the first input signal.

Duty cycle correction circuits that reduce distortion caused by mismatched transistor pairs

A ladder type clock network for reducing the skew of clock signals is provided. The clock network includes a buffer for buffering a clock signal, first delay units for delaying the output of the first buffer by a set time, second buffers connected to respective outputs of the first delay units, and second delay units connected to respective outputs of the second buffers. The first delay units and the second delay units consist essentially of the resistance and capacitance of lines through which the clock signal propagates. Accordingly, the skew of the internal clock signals is reduced, and internal clock signals having a stable duty with respect to variations in a semiconductor device manufacturing process, temperature, and power supply voltage, are generated.

Ladder type clock network for reducing skew of clock signals

An input buffer circuit for transforming pseudo differential input signals into full differential output signals wherein, the input buffer circuit includes a pull-up current source, two pull-down current sources, a differential input portion, and a positive feedback portion. The pull-up current source is formed of two PMOS transistors which are always in an &ldquo;on&rdquo; state, and provides an electric current. The two pull-down current sources are each formed of an NMOS transistor, which are always in an on state, and sink a pull-up electric current. The differential input portion is formed of two NMOS transistors, and receives an input signal and a reference signal, respectively. The positive feedback portion is formed of two NMOS transistors, and enlarges a voltage difference between two output terminals of the input circuit using positive feedback.

Input buffer circuit for transforming pseudo differential signals into full differential signals

A CMOS buffer circuit for preventing a short circuit current of an output buffer transistor that drives a load including a pre-driving stage, formed of even-numbered inverters connected in series, and the respective inverters are preferably designed to exponentially increase the driving capability; an output buffer driving stage, including a pull-up PMOS driving stage, which outputs a first signal, in response to an output signal of the pre-driving stage and an output signal of the pull-down NMOS driving stage and a pull-down NMOS driving stage, which outputs a second signal, in response to an output signal of the pre-driving stage and an output signal of the pull-up PMOS driving stage; and an output stage, an inverter formed of the pull-up PMOS transistor driven by the first signal and a pull-down NMOS transistor driven by the second signal, which drives a load connected to an output of the inverter.

CMOS buffer circuit

The present invention provides delay locked loop circuits, phase detectors and methods for producing a delayed signal from a periodic input signal. An intermediate delay signal as well as an input signal and a delayed output signal are provided to a delay control circuit that controls the delay of a delay circuit based on a comparison of the input signal and output signal following a transition of the intermediate signal. The apparatus and methods of the present invention may thereby be able to distinguish between a case in which tTOTAL&equals;T and tTOTAL&equals;,T to reduce the potential for locking in a false state.

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Suwon, South Korea

Chang-sik Yoo