公开(公告)号：US20130342124A1

公开(公告)日：2013-12-26

申请号：US13921523

申请日：2013-06-19

Applicant: Richtek Technology Corporation

Inventor： Tsung-Wei HUANG ,  Shui-Mu LIN ,  Huan-Chien YANG ,  Nang-Ching YEUNG ,  Ti-Ti LIU

IPC: H05B33/08

CPC classification number: H05B33/0839 ,  H05B33/0815 ,  H05B33/0827 ,  Y02B20/347

Abstract: A LED driver using a PWM signal for dimming control includes a power converter and a current regulator. The power converter provides an output voltage and a load current for a plurality of LEDs. The current regulator provides a load current dependent signal for the power converter to speed up load transient response caused by variation of the load current, to reduce the ripple of the output voltage, and thereby to avoid audio noise during PWM dimming.

Abstract translation: 使用PWM信号进行调光控制的LED驱动器包括功率转换器和电流调节器。 功率转换器为多个LED提供输出电压和负载电流。 电流调节器为功率转换器提供负载电流相关信号，以加速由负载电流变化引起的负载瞬态响应，以减少输出电压的纹波，从而避免PWM调光期间的音频噪声。

公开(公告)号：US20130249514A1

公开(公告)日：2013-09-26

申请号：US13829622

申请日：2013-03-14

Applicant: RICHTEK TECHNOLOGY CORPORATION

Inventor： Tsung-Wei HUANG ,  Shui-Mu LIN ,  Chueh-Kuei JAN ,  Chien-Yuan CHENG

IPC: H02M3/158

CPC classification number: H02M3/1582 ,  H02M3/158 ,  H03K17/102 ,  H03K17/122

Abstract: Serially connected low voltage transistors are used to replace a high voltage transistor in a voltage conversion circuit for a driver, or parallel connected sub-transistors are used to establish a high voltage transistor having an effective size dynamically adjusted according to loading of the driver, to reduce switching loss and thereby improve the efficiency of the driver.

Abstract translation: 串联的低压晶体管用于替代用于驱动器的电压转换电路中的高电压晶体管，或并联连接的子晶体管用于建立具有根据驱动器的负载动态调节的有效尺寸的高压晶体管， 降低开关损耗，从而提高驱动器的效率。

公开(公告)号：US20140320094A1

公开(公告)日：2014-10-30

申请号：US14223580

申请日：2014-03-24

Applicant: Richtek Technology Corporation

Inventor： Wei-Jen HUANG ,  Chueh-Kuei JAN ,  Tsung-Wei HUANG ,  Shui-Mu LIN

IPC: H02M3/156 ,  H02M3/158

CPC classification number: H02M3/156 ,  H02M2001/0032 ,  Y02B70/16

Abstract: A control circuit of a power converter includes: a zero current detection circuit for detecting a current flowing between an inductor and a voltage output terminal of the power converter to generate a zero current detection signal; an adjusting circuit for generating an adjustment signal according to the zero current detection signal; a clock signal generating circuit for adjusting a frequency of a clock signal according to the adjustment signal; a periodical signal generating circuit for generating a periodical signal according to the clock signal; an error detection circuit for generating an error signal; and a control signal generating circuit for generating a control signal to control operations of a power switch. If the and amount of pulses generated by the zero current detection circuit satisfy a predetermined condition, the adjusting circuit switches the power converter's operation mode from DCM to CCM.

Abstract translation: 电力转换器的控制电路包括：零电流检测电路，用于检测在电力转换器的电感器和电压输出端之间流动的电流以产生零电流检测信号; 调整电路，用于根据零电流检测信号产生调整信号; 时钟信号发生电路，用于根据调整信号调整时钟信号的频率; 周期信号发生电路，用于根据时钟信号产生周期信号; 用于产生误差信号的误差检测电路; 以及控制信号发生电路，用于产生控制信号以控制电源开关的操作。 如果由零电流检测电路产生的脉冲和量达到预定条件，则调节电路将电力转换器的操作模式从DCM切换到CCM。

公开(公告)号：US20130147385A1

公开(公告)日：2013-06-13

申请号：US13706219

申请日：2012-12-05

Applicant: Richtek Technology Corporation

Inventor： Shei-Chie YANG ,  Shui-Mu LIN ,  Jun-Sheng CHENG ,  Ming-Yu LIN ,  Chun-I LIN

IPC: H05B37/02

CPC classification number: H05B37/02 ,  H05B33/0848

Abstract: LED dimming control circuit and method compensate LED current or LED average current by LED characteristics to improve dimming efficiency and performance. LED characteristic related look-up tables are stored to provide compensation values, and input LED current setting information is compensated by the compensation values to generate corrected LED current setting information for determining LED brightness.

Abstract translation: LED调光控制电路和方法通过LED特性补偿LED电流或LED平均电流，提高调光效率和性能。 存储LED特征相关查找表以提供补偿值，并且通过补偿值补偿输入LED电流设置信息，以产生用于确定LED亮度的校正LED电流设置信息。