Renesas Electronics Corporation

Other

Keisuke Fukuda

Mamoru Kitamura

Motoaki Suzuki

Makoto Nakamura

Koji Igarashi

Hiroto Yamaguchi

Reika Igarashi

An LED drive method drives an LED by a drive current. The LED drive method uses a voltage conversion unit, which includes a coil and a first switch, and converts an external voltage into a first voltage, which is a DC voltage, by controlling the first switch to be on in an on-pulse period of a first drive signal. A constant current drive unit is provided with the first voltage and generates a drive current based on a second drive signal.

LED drive method and LED drive device

An LED lighting deviceaccording to this embodiment includes a lighting circuit that supplies a current to an LED, and a dimmerthat generates a PWM signal for controlling the supply of the current to the LED from the lighting circuit, in which the dimmerfeedback-controls the PWM signal that controls the supply of the current to the LED by comparing the output current to be output to the LED with a target current and feedforward-controls the PWM signal according to a fluctuation of an input voltage from a commercial power supply

LED lighting device and LED illuminating device

A semiconductor device configured to perform an A/D conversion of a wide range of signals is provided. A semiconductor device includes: an input voltage detection unit configured to detect an analog input voltage; a reference voltage setting unit configured to set a reference voltage based on the detected input voltage; an amplifier configured to amplify a difference between the input voltage and the reference voltage; an ADC configured to perform an A/D conversion of an amplified signal; and an arithmetic processing unit configured to calculate a digital voltage corresponding to the input voltage based on a result of the A/D conversion and the reference voltage.

Semiconductor device, power supply device and control method for semiconductor device

A voltage conversion unit including a coil and a first switch converts an AC voltage into a first voltage, which is a DC voltage, by controlling the first switch to be on in an on-pulse period of a first drive signal. A constant current drive unit is supplied with the first voltage and generates a drive current Id having a current value according to light control information. An LED control unit compares brightness based on the light control information and reference brightness, generates a first drive signal based on an error between the first voltage and a target voltage representing a target of the first voltage, when the brightness is higher than the reference brightness, and generates the first drive signal having a predetermined fixed on-pulse period when the brightness is lower than the reference brightness.

A method and a video game system that are capable of generating a field map with more natural geographical feature. The method and the video game system firstly divides the field map including a plurality of blocks into a first zone and a second zone by a boundary which consists of sides and comers in the blocks, then determines a first point for each side included in the boundary and a second point for each corner included in the boundary. Finally, the boundary is transformed into a more complex land shape by connecting the first points and the second points. The video game system includes a block division unit that divides the field map into a plurality of blocks, a block assign unit that assigns each of the divided blocks to either a first zone or a second zone using a boundary that consists of sides and comers of the blocks, a first point determining unit that determines a first point for each side, a second point determining unit that determines a second point for each corner, and a transforming unit that transforms the boundary by connecting the first points and the second points.

Growing community of inventors

Tokyo, Japan

Keisuke Fukuda