Fairchild Korea Semiconductor Ltd.

Elt Sensor Corp.

Donghwan Kim

Kunhee Cho

Young-Je Lee

Ihn Lee

Chang-ki Jeon

Sung-Yun Park

Yongcheol Choi

Minsuk Kim

The present invention provides an optical cavity for a gas sensor having a space defined therein, including: a first parabolic reflective surface formed on one wall surface in the space; a second parabolic reflective surface which is formed at a position facing the one wall surface, and is configured to reflect again a light emitted from a light source disposed at a focus of the first parabolic reflective surface and reflected by the first parabolic reflective surface so as to change a traveling path of the light; and a hyperbolic reflective surface formed so that any one focus of two foci coincides with a focus of the second parabolic reflective surface, and is configured to reflect the light made incident from the second parabolic reflective surface to change the traveling path of the light, and a value of c&#x2212;bof a hyperbola equation of hyperbola forming the hyperbolic reflective surface is in a range of 0&#x3c;c&#x2212;b&#x2264;4 mm.

Optical cavity for gas sensor and gas sensor having the same

Provided are an optical cavityfor a gas sensor which has a space therein and a gas sensor using the optical cavity, in which in the space of the optical cavity, an elliptical reflective surface, which constitutes a part of an ellipse () and reflects the light emitted from a position of one focal point Fof the ellipse to concentrate the light on the other focal point Fof the ellipse, is formed, a hyperbolic reflective surface, which constitutes a part of a hyperbola () having one focal point that coincides with the other focal point of the ellipse, and reflects the light, which is reflected by the elliptical reflective surface and concentrated on the other focal point of the ellipse, to concentrate the light on the other focal point fof the hyperbola, is formed, and a hyperbola centerline B-B', which connects one focal point of the hyperbola and the other focal point of the hyperbola, is inclined toward a side opposite to the elliptical reflective surface by a predetermined angle with respect to an ellipse centerline A-A&#x2032; which connects one focal point of the ellipse and the other focal point of the ellipse.

Optical cavity for gas sensor and gas sensor having optical cavity

The present invention relates to a clock signal generating circuit and a power supply including the same. The present invention includes: a counter for counting one period of an input clock signal by using a reference clock signal, and generating a count signal; and a clock signal generator for receiving the count signal and the reference clock signal, dividing the count signal to generate a quotient and a remainder, setting the quotient as a reference period of an output clock signal, and distributing and disposing the remainder to the output clock signal with a plurality of periods occurring for one period of the input clock signal.

Clock signal generating circuit and power supply including the same

The switch control device controls a switching operation of a power switch. The switch control device includes an auxiliary power device. The auxiliary power device includes a parasitic capacitor, and charges the parasitic capacitor by receiving a power voltage to generate an auxiliary power voltage. The switch control device includes a control pulse generator driven by the auxiliary power voltage and generating a set pulse and a reset pulse according to an input signal that is input for controlling the switching operation of the power switch. The switch control device generates a gate signal that turns on the power switch by being synchronized with the set pulse and generates a gate signal that turns off the power switch by being synchronized with the reset pulse.

Switch control device

Disclosed is a power semiconductor device including a bootstrap circuit. The power semiconductor device includes a high voltage unit that provides a high voltage control signal so that a high voltage is output; a low voltage unit that provides a low voltage control signal so that a ground voltage is output, and is spaced apart from the high voltage unit; a charge enable unit that is electrically connected to the low voltage unit and charges a bootstrap capacitor for supplying power to the high voltage unit when the high voltage is output, when the ground voltage is output; and a high voltage cut-off unit that cuts off the high voltage when the high voltage is output so that the high voltage is not applied to the charge enable unit, and includes a first terminal electrically connected to the charge enable unit and a second terminal electrically connected to the high voltage unit.

Growing community of inventors

Bucheon-si, South Korea

Donghwan Kim