Realtek Semiconductor Inc.

Li-Jun Gu

Ger-Chih Chou

Chih-Wei Chang

Gerchih Chou

Chun-Chi Yu

Fu-Chin Tsai

Bo-Yu Chen

Ming-Hui Tung

Guan-Yu Chen

Peng-Zhan Zhang

Ran Ding

The present disclosure discloses a memory access interface device. A data processing circuit receives a data signal including 2M pieces of data from a memory device. A sampling clock generation circuit receives a data strobe signal from the memory device to generate a valid data strobe signal having P valid strobe pulses and further generate a sampling clock signal accordingly, in which P is larger than M. A sampling circuit samples the data signal according to the sampling clock signal to generate sampling results. A control circuit determines valid sampling results according to a time difference between the valid data strobe signal and the data signal and outputs valid data generated according to the valid sampling results as a read data signal to a memory access controller.

Memory system and memory access interface device thereof

A clock circuit has a clock input terminal, a first clock output terminal, and a second clock output terminal. The clock circuit includes a pulse width adjustment module, a sampling module, a comparing module, and a differential signal converting module. A differential input terminal is electrically connected to a pulse width output terminal of the pulse width adjustment module. A positive differential signal output terminal and a negative differential signal output terminal are electrically connected to the first clock output terminal of the clock circuit and the second clock output terminal to output two clock signals with a phase difference of 180 degrees, respectively. A second input terminal of the sampling module is electrically connected to the second clock output terminal.

Clock circuit having a pulse width adjustment module

The present invention discloses a DDR4 memory I/O driver including a pre-driver, a pull-up circuit and a pull-down circuit. The pre-driver is coupled between a first high voltage terminal and a low voltage terminal to provide a first and a second pre-driving signals. The pull-up circuit includes: a driving PMOS transistor coupled between a second high voltage terminal and a pull-up resistor, that is coupled to an output pad, to operate according to the first pre-driving signal, in which the second high voltage terminal's voltage is not higher than the first high voltage terminal's voltage. The pull-down circuit includes: a driving NMOS transistor coupled between the low voltage terminal and a cascode NMOS transistor to operate according to the second pre-driving signal; and the cascode NMOS transistor coupled between the driving NMOS transistor and a pull-down resistor, that is coupled to the output pad, to operate according to a bias.

DDR4 memory I/O driver

A double data rate synchronous dynamic random access memory includes a control circuit and an output driving circuit. The control circuit provides a first voltage, a second voltage, a third voltage and a fourth voltage. The output driving circuit couples to the control circuit and includes a pull-up circuit, a pad and a pull-down circuit. When a voltage of the pad rises from the fourth voltage to the first voltage, a voltage between a drain and a source of a second driving transistor in the pull-down circuit is between the third voltage and the fourth voltage. When a voltage of the pad falls from the first voltage to the fourth voltage, a voltage between a drain and a source of a first driving transistor in the pull-up circuit is between the first voltage and the second voltage.

Double data rate synchronous dynamic random access memory and output driving circuit thereof

A phase interpolator, multi-phase interpolation device, interpolated clock generating method and multi-phase clock generating method is related to a phase interpolator with a differential to single-ended converter, a load circuit, two differential pairs, a current source and at least a switch pair. By using the switch pair to control the current providing for the two differential pairs from the current source, and through regulating the load of the load circuit and/or the reference current of the current source, the intersection of a first signal and a second signal is in the overlap duration between a first input clock and a second input clock, so that uniform multi-phase output clock signal can be interpolated.

Phase interpolator, multi-phase interpolation device, interpolated clock generating method and multi-phase clock generating method

The present invention is to provide a method and circuit for producing spread spectrum and over clock, which includes a primary circuit and a secondary circuit, wherein the primary circuit uses a frequency division technique based on phase swallow to achieve a high frequency resolution clock signal, and the secondary circuit multiplies the frequency of the output clock signal of the primary circuit, so as to expand its frequency range.

Growing community of inventors

Jiangsu, China

Li-Jun Gu