Abstract: A voltage calibration circuit includes a voltage output circuit, an amplifier, a notification circuit, and a built-in self-test circuit. The voltage output circuit selects a first voltage source to output an output voltage according to a selection signal. Two input terminals of the amplifier are for receiving the output voltage and a reference voltage corresponding to the first voltage source respectively. The notification circuit outputs a notification signal according to the reference voltage, a voltage at an output terminal of the amplifier and an indication voltage. The indication voltage and the output voltage have a fixed voltage difference. The built-in self-test circuit updates the selection signal according to the notification signal so that the voltage output circuit can select a second voltage source accordingly.

Abstract: A voltage converter with a sampling-hold and integrating circuit is provided herein. According to the minimum different value generated by the practical status of each of the illuminant channels in the LED backlight module, the sampling-hold and integrating circuit will generate an superposition voltage and the voltage converter can output different PWM signal to drive each of the illuminant channels in the backlight module. When the sampling-hold and integrating circuit of the voltage converter and the control device with adjusting pulse width function are embedded together to provide to the LED backlight module, the power saving is more convenient.

Abstract: A voltage converter with a sampling-hold and integrating circuit is provided herein. According to the minimum different value generated by the practical status of each of the illuminant channels in the LED backlight module, the sampling-hold and integrating circuit will generate an superposition voltage and the voltage converter can output different PWM signal to drive each of the illuminant channels in the backlight module. When the sampling-hold and integrating circuit of the voltage converter and the control device with adjusting pulse width function are embedded together to provide to the LED backlight module, the power saving is more convenient.