Seoul Semiconductor Co., Ltd.

Radina Co., Ltd

Hyung Jin Lee

Sang Wook Han

Sung Ho Jin

Keith Hopwood

Hyun Gu Kang

Young Do Jung

Yang Liu

Hyun Min Jang

Jae Kyu Yu

Dong Ryeol Lee

In Seok Baek

Hyeng Cheul Choi

An LED lighting apparatus capable of color temperature control includes a color temperature controller to receive a color temperature selection signal and output first and second control signals; a LED driver connected a plurality of LED groups; and a LED selection circuit including a first switch connected to a first node to which a rectified voltage is applied and receiving the first control signal, a first LED group selectively connected to the first node by the first switch, a second LED group connected in scales with the first LED group, a third LED group selectively connected to the first node by the first switch, a fourth LED group connected in series with the third LED group, and a second switch for selectively connecting the output terminal of the second LED group or the fourth LED group to the LED driver by receiving the second control signal.

LED lighting apparatus capable of color temperature control

An LED lighting apparatus capable of color temperature control includes a color temperature controller to receive a color temperature selection signal and output first and second control signals; a LED driver connected a plurality of LED groups; and a LED selection circuit including a first switch connected to a first node to which a rectified voltage is applied and receiving the first control signal, a first LED group selectively connected to the first node by the first switch, a second LED group connected in series with the first LED group, a third LED group selectively connected to the first node by the first switch, a fourth LED group connected in series with the third LED group, and a second switch for selectively connecting the output terminal of the second LED group or the fourth LED group to the LED driver by receiving the second control signal.

A lighting apparatus including an LED circuit including a plurality of serially connected stages configured to receive a modulated rectified voltage, each of the stages including a first path including a first resistor and a first LED connected in series, and a second path connected to the first path in parallel and including a second LED configured to emit light having a color temperature different from that emitted from the first LED, and a driving current controller configured to adjust an intensity of light output from the LED circuit by adjusting currents applied to driving nodes connected to the stages, depending on a dimming signal associated with a dimming level of the rectified voltage, in which a threshold voltage of the first LED is lower than that of the second LED.

Lighting apparatus including light-emitting diodes

A light-emitting diode (LED) lighting apparatus including at least one LED group including a plurality of LEDs, a rectifier configured to rectify an alternating current (AC) voltage and generate a driving voltage for the at least one LED group, and a system-in-package (SIP) configured to drive and control the at least one LED group, in which the SIP is connected to the at least one LED group and the rectifier, and includes a driving module, a functional module, and a first resistor disposed on a single substrate.

System-in-package for LED driving and LED lighting device including the same

Disclosed are a light emitting diode (LED) driver circuit having improved flicker performance and an alternating current-driving type LED lighting device including the same. The LED driver circuit can remove an LED off period using a charging and discharging circuit during a compensation period so as to reduce light output deviation of an LED lighting device, and provide a driving voltage to another element of the LED lighting device, using the charging and discharging circuit during an additional discharging period so as to simultaneously improve power efficiency.

LED drive circuit having improved flicker performance and LED lighting device including the same

An AC-driven LED lighting apparatus includes: a triac dimmer to generate a modulated AC voltage by modulating a phase of AC power according to a selected level of dimming; a rectifying circuit to generate drive voltage by full-wave-rectifying the AC voltage having the phase modulated by the triac dimmer; a dimming level detector to detect a dimming level according to the drive voltage; a phase cut reference setting unit for setting a phase cut reference value; and a LED driving module for constant-current-controlling a plurality of LED groups by comparing the detected dimming level with the phase cut reference value, wherein the light emitting element driving module comprises a LED current blocking unit for blocking a drive current supplied to the plurality of LED groups when the dimming level is lower than the phase cut reference value.

Alternating current-driven light emitting element lighting apparatus

An LED lighting apparatus according to exemplary embodiments includes a rectification circuit configured to rectify a modulated AC voltage to generate a drive voltage, an LED driving module connected to a plurality of LED groups and configured to apply a drive current to at least one of the plurality of LED groups according to a level of the drive voltage, and a dimming level detector configured to detect a dimming level corresponding to the drive voltage. The LED driving module is configured to compare the detected dimming level to a reference value and block the drive current based on a result of the comparison.

By providing a radiator configuration circuit and a feeding circuit each having a simple structure, a ground radiation antenna having a more simplified fabrication process as well as a remarkably reduced fabrication cost is provided herein. Additionally, a ground radiation antenna having an excellent radiation performance, even when one side of a mobile communication terminal is covered with a conductive substance, such as an LCD panel, is also provided herein.

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Ansan-si, South Korea

Hyung Jin Lee