Nec Corporation

Mikihiro Kajita

Masayuki Mizuno

Koichi Nose

Eisuke Saneyoshi

Junichi Tsuchida

A power-supply noise measuring circuit includes a voltage fluctuation detecting circuit, a unit time generating circuit, a current measuring circuit, and a sampling circuit. The voltage fluctuation detecting circuit generates a detection current in accordance with a voltage fluctuation of a power supply. The unit time generating circuit generates a unit time in accordance with a clock signal. The current measuring circuit treasures an amount of the detection current per unit time. The sampling circuit samples the amount of the detection current measured by the current measuring circuit, every unit time. The present invention provides the power-supply noise measuring circuit that has a small circuit area and enough accuracy.

Power supply noise measuring circuit and power supply noise measuring method

Current reading means detects an output current of a current source whose output current varies with a variation in temperature and outputs a value proportional to the output current. The temperature of the current source corresponding to the output value of the current reading means which is proportional to the output current of the current source is measured, and a parameter for converting the output value to temperature information is determined from the output value of the current reading means and the measured value of the temperature of the current source corresponding to the output value. The output value of the current reading means is converted to the temperature information using the determined parameter.

Temperature measuring device and method

A power supply noise reduction circuit and a power supply noise reduction method for reducing power supply noise at any frequency, includes forcing a power supply noise to resonate to the resonance frequency of a parallel resonance circuit, including an inductor and a capacitor to set the frequency of the noise equal or close to the resonance frequency of the parallel resonance circuit and, attenuating the noise, set equal or close to the resonance frequency of the parallel resonance circuit, using a low-pass filter including a resistor and a capacitor.

Power supply noise reduction circuit and power supply noise reduction method

An apparatus includes a current source, a current monitor circuit which monitors a current amount of the current source, and outputs a current amount signal corresponding to the current amount being monitored, a counter circuit which counts a count value based on the current amount signal, the count value corresponding to a period being taken until when the current amount reaches a predetermined value, and a control circuit which modifies an operation parameter for operating a circuit unit according to the count value.

Apparatus, circuit and method of monitoring leakage current characteristics

An apparatus includes a first sequential circuit which captures an input signal according to a first clock signal, a second sequential circuit which captures the input signal according to a second clock signal and outputs the captured input signal to a logic circuit, the second clock signal being modulated so that a period of the second clock signal is shorter than that of the first clock signal, a third sequential circuit which captures an output signal of the logic circuit according to the second clock signal, and a verification circuit which verifies whether an output signal of the first sequential circuit and an output signal of the third sequential circuit match with each other.

Apparatus, circuit and method of monitoring performance

A power supply noise measuring circuit and measuring method are provided which are capable of evaluating a frequency component of power supply noise that affects performance and functions in a circuit by using a cross-correlation function. The power supply noise measuring circuit includes a SIN wave generating circuit which generates a sine wave signal having a variable frequency in a constant amplitude, a cross-correlation processing circuit which calculates and output a cross-correlation function between power supply noise and a sine wave signal fed from the SIN wave generating circuit, a comparator which compares a cross-correlation function output with a specified threshold voltage and which generates an output when the cross-correlation function output exceeds the threshold voltage, and a counter which counts the number of occurrences of the output from the comparator within a specified time of period.

To provide a signal measuring circuit that measures a signal, such as noise, with high precision. A maximum reference value and a minimum reference value are generated based on the voltage level of a signal, the voltage difference between the maximum reference value and the minimum reference value is divided, a reference value is generated according to the divided voltage, and the voltage level of the signal is compared with the reference value, thereby measuring the signal.

Signal measuring circuit and signal measuring method

According to one embodiment, a signal from a power supply line is caused to pass through a high pass filter, and a first signal is generated by adding a voltage-divided signal to the signal. In addition, a second signal obtained by adding the voltage-divided signal to an identification voltage is generated. A comparator outputs a comparison result of comparing a voltage of the first signal with a voltage of the second signal, and a counter counts up a count value when the voltage of the first signal is higher than that of the second signal. A sample hold circuit sample-holds the count value just before the counter is reset.

Power supply noise measuring device

This invention provides a vertical-cavity surface-emitting laser device comprising a surface light-emitting part comprising a cavity consisting of two multilayer reflectors and an active region between them and a waveguide part for introducing induced light into the surface light-emitting part. The device is substantially independent of a temperature and allows a wavelength to be controlled after manufacturing the device.

Vertical-cavity surface-emitting laser device

A system that affords synchronization signals for adjusting the skew in parallel transmission without producing data overhead to enable high-efficiency large-capacity transmission. On a transmitter side, a transmitter outputs two wavelengths. The transmitter transmits the data signals for transmission as it switches from a first wave length to a second wavelength at a certain synchronization timing. A wavelength filter separates a first wavelength and a second wavelength on a receiving side at the pre-stages of receivers receiving the data signals of the respective transmission paths. Data D and D , separated in association with the first and second wave lengths, are stored in buffers B , B to detect oncoming of data signals with maximum delay in the respective transmission paths. The data are output simultaneously from the second buffer B to the respective transmission paths in a timing of the data having the maximum delay.

Parallel transmission method and system

In a device fabrication method, there are prepared a first substrate having registration patterns formed thereon and a second substrate having through bores formed therein and devices formed thereon through a separation layer. The two substrates are overlapped by viewing the registration patterns through the through bores. After the first substrate and the devices formed on the second substrate have been bonded, the devices are separated from the second substrate by selectively etching the separation layer, and are transferred to the first substrate.

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Tokyo, Japan

Mikihiro Kajita