Abstract: A circuit for reference current and voltage generation is provided. The circuit comprises a current bias circuit and a voltage reference circuit. Wherein, the current bias circuit receives an enable signal, provides a reference current, a bias signal and a startup signal when the enable signal is in an enabling state, and provides a first predetermined voltage and a second predetermined voltage when the enable signal is in a disabling state. The voltage reference circuit is electrically coupled to the current bias circuit. In addition, the voltage reference circuit enters into a turned-on state and provides a reference voltage after receiving the bias signal and the enable signal, and enters into a turned-off state after receiving the first and the second predetermined voltages.

Abstract: A adaptive pole and zero and Pole-Zero Cancellation Control Low Drop-Out (LDO) regulator is provided, which includes a regulation unit, an error amplifier, a Miller Effect Pole control unit, a Pole Zero Cancellation delay unit, and a feedback network. Pole and Zero could be adaptive regulated depend on various loads and maintain stably in a perfect phase margin.

Abstract: A voltage regulator with output accelerated recovery circuit is disclosed, which is substantially a low dropout voltage regulator (LDO) having a comparator and a pull-down transistor, both being connected between the positive feedback input node of its operational amplifier (OP) and the ground end thereof. In a preferred aspect, the comparator is used for detecting the voltage variation of a reference node, whereas the reference node is defined to be a node located between a first feedback resistor and a second feedback resistor. Operationally, as the voltage detected at the reference node is larger than a predetermined voltage, the pull-down transistor is forced to turn on so as to sink the output voltage rapidly for returning the same back into regulation.

Abstract: A backlight device includes a light source module having a plurality of light sources, a detecting circuit, a control unit, and a pulse width modulation (PWM) driving circuit. The detecting circuit is used for detecting the brightness of the light source module and generating a detecting signal to the control unit, such that the control unit outputs a control signal according to the detecting signal. In addition, the PWM driving circuit is used for generating a PWM signal for driving the light source module. In the present invention, the PWM driving circuit adjusts the base frequency of the PWM signal according to the control signal without adjusting the duty cycle of the PWM signal, so as to control the brightness of the light sources.

Abstract: A power supply apparatus and an operation-mode determining unit and a method thereof are provided. The power supply apparatus includes first and second control units, a switching unit, a power output unit, and an operation-mode determining unit. The first and second control units provide first and second control signals respectively. The switching unit selects to output the first or second control signal according to a switching signal. The power output unit adjusts its output power in accordance with the control signal output from the switching unit. The operation-mode determining unit compares an operation frequency in the power output unit with a reference frequency, and detects an inductor current in the power output unit. The operation-mode determining unit determines the state of a switching signal and outputs it to the switching unit in accordance with the comparison result and the detection result.

Abstract: A backlight device includes a light source module having a plurality of light sources, a detecting circuit, a control unit, and a pulse width modulation (PWM) driving circuit. The detecting circuit is used for detecting the brightness of the light source module and generating a detecting signal to the control unit, such that the control unit outputs a control signal according to the detecting signal. In addition, the PWM driving circuit is used for generating a PWM signal for driving the light source module. In the present invention, the PWM driving circuit adjusts the base frequency of the PWM signal according to the control signal without adjusting the duty cycle of the PWM signal, so as to control the brightness of the light sources.

Abstract: The invention proposes a low dropout voltage regulator, including a feedback circuit, an operational amplifier, a transconductor, a current mirror, and a power transistor. The feedback circuit provides a voltage according to a current provided by the power transistor. An invert-phase input terminal of the operational amplifier is coupled with the feedback circuit, and the positive-phase input terminal of the operational amplifier receives a reference voltage. The transconductor is coupled to an output terminal of the operational amplifier, and controls the current, which is fed to the transconductor from the current mirror, according to the output voltage from the operational amplifier. The current mirror is coupled with the transconductor and drives the power transistor. The power transistor is coupled between the current mirror and the feedback circuit, so as to provide current to the feedback circuit.

Abstract: The invention proposes a low dropout voltage regulator, including a feedback circuit, an operational amplifier, a transconductor, a current mirror, and a power transistor. The feedback circuit provides a voltage according to a current provided by the power transistor. An invert-phase input terminal of the operational amplifier is coupled with the feedback circuit, and the positive-phase input terminal of the operational amplifier receives a reference voltage. The transconductor is coupled to an output terminal of the operational amplifier, and controls the current, which is fed to the transconductor from the current mirror, according to the output voltage from the operational amplifier. The current mirror is coupled with the transconductor and drives the power transistor. The power transistor is coupled between the current mirror and the feedback circuit, so as to provide current to the feedback circuit.

Abstract: A circuit for reference current and voltage generation is provided. The circuit comprises a current bias circuit and a voltage reference circuit. Wherein, the current bias circuit receives an enable signal, provides a reference current, a bias signal and a startup signal when the enable signal is in an enabling state, and provides a first predetermined voltage and a second predetermined voltage when the enable signal is in a disabling state. The voltage reference circuit is electrically coupled to the current bias circuit. In addition, the voltage reference circuit enters into a turned-on state and provides a reference voltage after receiving the bias signal and the enable signal, and enters into a turned-off state after receiving the first and the second predetermined voltages.