公开(公告)号：US09179517B2

公开(公告)日：2015-11-03

申请号：US13966075

申请日：2013-08-13

Applicant: RICHTEK TECHNOLOGY CORPORATION

Inventor： Chiawei Liao ,  Jing-Meng Liu

IPC: H05B37/02 ,  H05B33/08 ,  G02F1/1335

CPC classification number: H05B33/089 ,  G02F1/133603 ,  G02F2001/133612

Abstract: The present invention discloses a backlight control circuit, comprising: a voltage supply circuit for receiving an input voltage and generating an output voltage under control by a control signal; at least one voltage comparison path respectively coupled to at least one light emission device path; a voltage operative amplifier circuit for generating the control signal according to a lowest voltage on the at least one voltage comparison path; and at least one under current detection circuit for detecting whether a corresponding one of the at least one light emission device path is in an under current status, whereby when anyone of the under current detection circuits detects the under current status, it sends an exclusion signal excluding a corresponding one of the at least one voltage comparison path from being an effective input of the voltage operative amplifier.

Abstract translation: 本发明公开了一种背光控制电路，包括：电压供给电路，用于接收输入电压，并通过控制信号控制输出电压; 至少一个电压比较路径分别耦合到至少一个发光器件路径; 电压操作放大器电路，用于根据所述至少一个电压比较路径上的最低电压产生所述控制信号; 以及至少一个欠电流检测电路，用于检测所述至少一个发光器件路径中的相应一个是否处于低电流状态，由此当所述欠电流检测电路中的任何一个检测到所述欠电流状态时，发送排除信号 不包括所述至少一个电压比较路径中的相应一个电压作为所述电压运算放大器的有效输入。

公开(公告)号：US09629214B2

公开(公告)日：2017-04-18

申请号：US14718045

申请日：2015-05-20

Applicant: RICHTEK TECHNOLOGY CORPORATION

Inventor： Chiawei Liao ,  Jing-Meng Liu

IPC: H05B33/00 ,  H05B33/08 ,  G09G3/34

CPC classification number: H05B33/0845 ,  G09G3/3406 ,  G09G2330/04 ,  H05B33/0812 ,  H05B33/0827 ,  H05B33/089 ,  Y02B20/345

Abstract: The present invention discloses a backlight control circuit with flexible configuration, comprising: a light emitting device path; a current source for controlling the current amount on the light emitting device path, the current source receiving a relatively high reference voltage in a first state, and receiving a relatively low reference voltage in a second state; and a current source control circuit for controlling the current source, whereby when the light emitting device path is in normal use, the current source is set to the first state, and when the light emitting device path is not in normal use, the current source is set to the second state.