Koito Manufacturing Company, Ltd.

Shohei Yanagizu

Satoshi Kikuchi

Takao Muramatsu

Masashi Kato

Yu Ota

Masayasu Ito

Tomoyuki Ichikawa

Kentarou Murakami

Toshiyuki Tsuchiya

An array-type light-emitting device includes multiple pixel circuits electrically coupled in parallel and spatially arranged in a matrix. A power supply circuit supplies electric power to the array-type light-emitting device. A DC/DC converter has an output coupled to a power supply terminal of the array-type light-emitting device via a power supply line. A power supply control circuit sets a target value that corresponds to a light distribution pattern, and controls the DC/DC converter such that the control target voltage approaches the target value.

Vehicular lamp system, power supply circuit

A variable light distribution light source includes an array-type light-emitting device. The array-type light-emitting device includes a power supply terminal and multiple pixel circuits electrically coupled and spatially arranged in a matrix. A power supply circuit includes a power supply unit that supplies electric power to the array-type light-emitting device. An output of a DC/DC converter is coupled to the power supply terminal VDD of the array-type light-emitting device via an output terminal. A voltage setting circuit generates a controllable correction voltage. A feedback circuit generates a feedback voltage based on the correction voltage and the control target voltage that corresponds to the output voltage of the DC/DC converter, and supplies the feedback voltage to a feedback pin of a converter controller.

Automotive lamp system

A scanning light source includes a light source, and scans the output light of the light source ahead of a lamp. A control apparatus controls the lighting on/off state of the semiconductor light source in synchronization with the scanning operation of the scanning light source. The control apparatus judges the presence or absence of an abnormal state with at least one from among (i) a timing immediately before switching from a lighting-on state to a lighting-off state and (ii) a timing immediately before switching from a lighting-off state to a lighting-on state as a judgment timing.

Automotive lamp

There is provided a lighting circuit configured to drive a light emitting unit including a first light source and a second light source connected in series. The lighting circuit includes a first pin connected to one end of the first light source, a second pin connected to a connection node of the first light source and the second light source, a third pin connected to one end of the second light source, a drive circuit configured to supply a drive current to the light emitting unit, a bypass switch provided between the second pin and the third pin, a first resistor provided in parallel with the bypass switch between the second pin and the third pin, and an abnormality detection circuit configured to detect abnormality based on a detection voltage generated between the second pin and the third pin when an ON signal is applied to the bypass switch.

Growing community of inventors

Shizuoka, Japan

Shohei Yanagizu