Citizen Electronics Co., Ltd.

Citizen Watch Company, Ltd.

Citizen Holdings Company, Ltd.

Yuki Ochiai

Takashi Akiyama

Shigehisa Watanabe

Yuki Nishikawa

Tatsuro Yamada

Yasuaki Kayanuma

Hidekazu Arai

Satoshi Goto

The purpose of the present invention is to reduce the size and thickness of an LED module. The LED module includes a circuit substrate, at least two supply terminals, a plurality of LED dies, a plurality of FET die, a constant current circuit, a dam member, a fluorescent resin, a resistor network, and a bypass circuit, wherein the constant current circuit includes one of the plurality of FET die and the bypass circuit includes other of the plurality of FET die, a portion of the dam enclosing the LED block region forms a portion of the dam enclosing the circuit block region, and the dam member enclosing the LED block region has a annular shape and the dam member enclosing the circuit block region has a rectangular shape except for said portion of the dam member.

Packaging of LED chips and driver circuit on the same substrate

Light-emitting diode

An LED illuminator configured to further reduce total harmonic distortion is provided. The LED illuminator has: a first LED string including a first partial LED string and a second partial LED string; a second LED string including a third partial LED string and a fourth partial LED string; a first switching circuit configured to switch between a state where only the first partial LED string is connected to a rectifier and a state where the first partial LED string and the second partial LED string connected in series are connected to the rectifier as a full-wave rectified voltage waveform that is output from the rectifier increases/decreases; and a second switching circuit configured to switch between a state where only the third partial LED string is connected to the rectifier and a state where the third partial LED string and the fourth partial LED string connected in series are connected to the rectifier, and the switching timing by the first switching circuit and the switching timing by the second switching circuit are set so as to differ from each other.

LED illumination device

The purpose of the present invention is to reduce the size and thickness of an LED module in which a plurality of LED dies along with other electronic components are mounted on a circuit board, and at the same time to stabilize the operation of the module with respect to source voltage fluctuation. The LED module includes: a circuit board; a plurality of LED dies that are mounted on one surface of a circuit board as bare chips and constitute a series circuit; an FET die that is mounted on the one surface of a circuit board as bare chips and controls a current flowing through the plurality of LED dies; and a constant current circuit that is mounted on the one surface of a circuit board and is series-connected to the series circuit. The constant current circuit includes the FET die.

LED module

Growing community of inventors

Yamanashi-ken, Japan

Yuki Ochiai