Abstract: An adaptive equalizer circuit includes an equalizer circuit configured to produce an output data signal in response to an equalizing factor, a data detecting circuit configured to detect a signal level of the output data signal in a given unit time at predetermined timing, a boundary detecting circuit configured to detect a signal level of the output data signal at a timing that is ½ unit time away from the predetermined timing, and a control unit configured to detect, multiple times, a pattern having consecutive data items of a first value followed by a data item of a second value, and to adjust the equalizing factor such that a data detection value and a boundary detection value obtained for the data item of the second value are equal to each other a certain percentage of times, and are different from each other substantially the same percentage of times.

Abstract: A semiconductor integrated circuit device has a command decoder for issuing a control command in accordance with a supplied control signal, a DRAM core, and a timing adjusting circuit for supplying the control command, set active for a predetermined period, as a DRAM control signal to the DRAM core. The timing adjusting circuit generates n different clocks that are respectively shifted in phase with respect to a supplied reference clock, and generates the DRAM control signal by setting the control command active in a prescribed operation cycle for only a period starting at a first predetermined clock pulse of a first clock of the n clocks and ending at a second predetermined clock pulse of a second clock of the n clocks. In this way, timing design with relatively high accuracy of adjustment can be done in a short period.

Abstract: An adaptive equalizer circuit includes an equalizer circuit configured to produce an output data signal in response to an equalizing factor, a data detecting circuit configured to detect a signal level of the output data signal in a given unit time at predetermined timing, a boundary detecting circuit configured to detect a signal level of the output data signal at a timing that is ½ unit time away from the predetermined timing, and a control unit configured to detect, multiple times, a pattern having consecutive data items of a first value followed by a data item of a second value, and to adjust the equalizing factor such that a data detection value and a boundary detection value obtained for the data item of the second value are equal to each other a certain percentage of times, and are different from each other substantially the same percentage of times.

Abstract: A semiconductor integrated circuit device has a command decoder for issuing a control command in accordance with a supplied control signal, a DRAM core, and a timing adjusting circuit for supplying the control command, set active for a predetermined period, as a DRAM control signal to the DRAM core. The timing adjusting circuit generates n different clocks that are respectively shifted in phase with respect to a supplied reference clock, and generates the DRAM control signal by setting the control command active in a prescribed operation cycle for only a period starting at a first predetermined clock pulse of a first clock of the n clocks and ending at a second predetermined clock pulse of a second clock of the n clocks. In this way, timing design with relatively high accuracy of adjustment can be done in a short period.

Abstract: A semiconductor integrated circuit device has a command decoder for issuing a control command in accordance with a supplied control signal, a DRAM core, and a timing adjusting circuit for supplying the control command, set active for a predetermined period, as a DRAM control signal to the DRAM core. The timing adjusting circuit generates n different clocks that are respectively shifted in phase with respect to a supplied reference clock, and generates the DRAM control signal by setting the control command active in a prescribed operation cycle for only a period starting at a first predetermined clock pulse of a first clock of the n clocks and ending at a second predetermined clock pulse of a second clock of the n clocks. In this way, timing design with relatively high accuracy of adjustment can be done in a short period.

Abstract: A hybrid circuit includes a resistor inserted serially between a transmission line and an output driver for transmitting a signal; and a reception signal extraction unit for extracting only a reception signal from a signal existing in a transmission path by using a signal obtained from both ends of the resistor. The reception signal extraction unit can be constituted by, for example, two transconductance amplifiers for converting the input voltage into a current and a load resistor in which flows the current of a result of adding the output currents of the two amplifiers.

Abstract: A signal transmission system has a plurality of signal lines, a plurality of transmitting circuits, a plurality of receiving circuits, and a timing adjusting circuit. The transmitting circuits are provided for the signal lines. Each of the receiving circuits receives a signal from a corresponding one of the transmitting circuits via the signal lines. The timing adjusting circuit, which is provided at the same side as the transmitting circuits, adjusts signal latch timing for the receiving circuits to optimum timing in accordance with signal skew caused between the signal lines. Therefore, a large-capacity and error free transmission can be performed at high speed using a plurality of signal lines without being affected by skew on each of the signal lines.

Abstract: A multiplexer circuit, converting parallel data into serial data and synchronized with a clock signal, has a plurality of multiplexer cells that receive the parallel data. Each of the multiplexer cells has a first load, a plurality of first conductivity type transistors, and a level-changing circuit. The first conductivity type transistors are connected in series between a first power source line and a second power source line, and the level-changing circuit changes a connection node of adjacent first conductivity type transistors to a level of the first power source line.

Abstract: A clock recovery circuit has a boundary detection/discrimination circuit to detect and discriminate a boundary in an input signal in accordance with a first signal. The clock recovery circuit performs clock recovery by controlling the timing of the first signal in accordance with the detected boundary, wherein boundary detection timing in the boundary detection/discrimination circuit is varied by controlling the first signal.

Abstract: A test circuit is incorporated in a device having an output circuit for outputting a signal, and the test circuit carries out a verification of a connection of nodes of the device. The test circuit has a test data generating circuit and a test output buffer connected in parallel with output nodes of the output circuit. The test data generating circuit generates test data for carrying out a verification of a connection of the output nodes, and the test output buffer receives test data from the test data generating circuit and outputs the test data to the output nodes. Similarly, a test circuit is incorporated in a device having an input circuit for inputting a signal, and the test circuit carries out a verification of a connection of nodes of the device. The test circuit has a test data generating circuit and a test input buffer connected in parallel with input nodes of the input circuit.

Abstract: A driver circuit transmits a signal to a receiver circuit through a signal transmission line. The driver circuit has an output driver, a front driver, and a level adjuster. The front driver drives the output driver, and the level adjuster adjusts the output level of the front driver. The output driver generates a signal whose level is variable in response to an output level of the front driver.

Abstract: A multiplexer circuit, converting parallel data into serial data and synchronized with a clock signal, has a plurality of multiplexer cells that receive the parallel data. Each of the multiplexer cells has a first load, a plurality of first conductivity type transistors, and a level-changing circuit. The first conductivity type transistors are connected in series between a first power source line and a second power source line, and the level-changing circuit changes a connection node of adjacent first conductivity type transistors to a level of the first power source line.

Abstract: A test circuit is incorporated in a device having an output circuit for outputting a signal, and the test circuit carries out a verification of a connection of nodes of the device. The test circuit has a test data generating circuit and a test output buffer connected in parallel with output nodes of the output circuit. The test data generating circuit generates test data for carrying out a verification of a connection of the output nodes, and the test output buffer receives test data from the test data generating circuit and outputs the test data to the output nodes. Similarly, a test circuit is incorporated in a device having an input circuit for inputting a signal, and the test circuit carries out a verification of a connection of nodes of the device. The test circuit has a test data generating circuit and a test input buffer connected in parallel with input nodes of the input circuit.

Abstract: A signal transmission system has a plurality of signal lines, a plurality of transmitting circuits, a plurality of receiving circuits, and a timing adjusting circuit. The transmitting circuits are provided for the signal lines. Each of the receiving circuits receives a signal from a corresponding one of the transmitting circuits via the signal lines. The timing adjusting circuit, which is provided at the same side as the transmitting circuits, adjusts signal latch timing for the receiving circuits to optimum timing in accordance with signal skew caused between the signal lines. Therefore, a large-capacity and error free transmission can be performed at high speed using a plurality of signal lines without being affected by skew on each of the signal lines.

Abstract: A signal transmission system has a response time of a signal transmission line which is set approximately equal to or longer than the length of a transmitted symbol. More specifically, terminal resistance is set larger than the characteristic impedance of the signal transmission line, driver output resistance is set to a large value, or a damping resistor is provided in series with the signal transmission line. With this configuration, signal power can be reduced drastically.

Abstract: A clock recovery circuit has a boundary detection/discrimination circuit to detect and discriminate a boundary in an input signal in accordance with a first signal. The clock recovery circuit performs clock recovery by controlling the timing of the first signal in accordance with the detected boundary, wherein boundary detection timing in the boundary detection/discrimination circuit is varied by controlling the first signal.

Abstract: A semiconductor integrated circuit device has a command decoder for issuing a control command in accordance with a supplied control signal, a DRAM core, and a timing adjusting circuit for supplying the control command, set active for a predetermined period, as a DRAM control signal to the DRAM core. The timing adjusting circuit generates n different clocks that are respectively shifted in phase with respect to a supplied reference clock, and generates the DRAM control signal by setting the control command active in a prescribed operation cycle for only a period starting at a first predetermined clock pulse of a first clock of the n clocks and ending at a second predetermined clock pulse of a second clock of the n clocks. In this way, timing design with relatively high accuracy of adjustment can be done in a short period.

Abstract: A driver circuit transmits a signal to a receiver circuit through a signal transmission line. The driver circuit has an output driver, a front driver, and a level adjuster. The front driver drives the output driver, and the level adjuster adjusts the output level of the front driver. The output driver generates a signal whose level is variable in response to an output level of the front driver.

Abstract: A signal transmission system has a response time of a signal transmission line which is set approximately equal to or longer than the length of a transmitted symbol. More specifically, terminal resistance is set larger than the characteristic impedance of the signal transmission line, driver output resistance is set to a large value, or a damping resistor is provided in series with the signal transmission line. With this configuration, signal power can be reduced drastically.

Abstract: A driver circuit transmits a signal to a receiver circuit through a signal transmission line. The driver circuit has an output driver, a front driver, and a level adjuster. The front driver drives the output driver, and the level adjuster adjusts the output level of the front driver. The output driver generates a signal whose level is variable in response to an output level of the front driver.