Novatek Microelectronics Corp.

Kuang-Feng Sung

Ji-Ting Chen

Min-Chieh Hsu

Chao-An Chen

Yen-Cheng Cheng

Wing-Kai Tang

Tsung-Hau Chang

Yueh-Hsiu Liu

Chun-Yi Chou

Jin-Sheng Hsieh

Wei-Ta Chiu

Tsun-Tu Wang

A channel circuit of source driver and an operation method thereof are provided. The channel circuit includes a digital-to-analog converter (DAC), a first switch, an output buffer circuit and a pre-charge circuit. The terminals of the first switch are coupled to the first output terminal of the DAC and the first input terminal of the output buffer circuit, respectively. The pre-charge circuit is coupled to the first input terminal of the output buffer circuit. The pre-charge circuit pre-charges the first input terminal of the output buffer circuit when the first switch is turned off during a pre-charge period, and not to pre-charge the first input terminal of the output buffer circuit when the first switch is turned on during a normal operation period.

Channel circuit of source driver and operation method thereof

The present disclosure provides a driving device for driving a liquid crystal display (LCD) device. The driving device comprises a plurality of first charge sharing switches and a plurality of second charge sharing switches. Each of the plurality of first charge sharing switches is individually coupled between two adjacent odd data channels of a plurality of data channels. Each of the plurality of second charge sharing switches is individually coupled between two adjacent even data channels of the plurality of data channels.

Driving device including charge sharing for driving liquid crystal display device

A driving method for a Liquid Crystal Display (LCD) device is used for reducing power consumption of the LCD device. The driving method includes determining a driving approach of the LCD device, and performing corresponding charge sharing on a plurality of data channels according to the driving approach. The driving approach of the LCD device is determined according to a latch data (LD) signal and a polarity signal.

Driving method including charge sharing and related liquid crystal display device

A driving apparatus and a driving method thereof are provided. The driving apparatus includes a digital to analog converter and a signal amplifier. The digital to analog converter is used for receiving a digital data and converting the digital data to an analog signal. The signal amplifier is coupled to the digital to analog converter. The signal amplifier is used for receiving the analog signal to generate a driving signal. The signal amplifier also dynamically changes the driving ability of the driving signal according to at least one bit of the digital data.

Driving apparatus and driving method thereof

A source driver includes an output buffer for outputting a driving signal; a first current path coupled between the output buffer and a data line; and a second current path coupled in parallel to the first current path. During a first driving period, the output buffer utilizes both the first current path and the second current path to drive the data line. During a second driving period, the output buffer utilizes only the first current path to transmit the driving signal so as to improve the stability of the source driver.

Source driver with charge sharing

A thin film transistor (TFT) liquid crystal display panel driving device and a method thereof are provided. The TFT liquid crystal display panel driving device is characterized by including a modulation signal generator for providing at least one modulation signal to at least one output buffer of a source driver of the TFT liquid crystal display panel. The output buffer(s) has chopper function. Each output buffer changes the offset voltages of the pixels of a same frame under the control of different modulation signals, thus eliminating the effect of the offset voltages of the output buffer(s) on the display quality.

TFT LCD device and driving method with a chopper amplifier that allows offset voltage polarity interlace within one frame

A source driver includes four output switches, two resistors, and a charge-sharing switch. The first output switch and the first resistor are coupled in series to a first output channel of the source driver. The second output switch and the second resistor are coupled in series to a second output channel of the source driver. The third output switch is coupled in parallel to the first output switch. The fourth output switch is coupled in parallel to the second output switch. The charge-sharing switch is coupled between the first resistor and the second resistor. The third output switch and the fourth output switch are controlled to adjust the resistance of the output current path of the source driver.

A digital-to-analog converter with high driving capability includes a voltage generator for generating voltages, a voltage division circuit coupled to the voltage generator for outputting a plurality of reference voltages according to voltages generated by the voltage generator, a decode unit for decoding a digital signal, a switch circuit coupled to the voltage division circuit and the decode unit for switching to output one of the plurality of reference voltages, and a current generator coupled to the voltage division circuit for generating currents to the voltage division circuit.

Digital to analog converter with high driving capability

An operational amplifier with a rail-to-rail common-mode input and output range comprises a differential input stage consisting of a first differential pair and a second differential pair for receiving an input signal; a summing circuit coupled to the differential input stage for outputting a summation result of the output signals of the first differential pair and second differential pair; and a push-pull output stage coupled to the summing circuit for outputting an amplified signal comprising an output terminal for outputting the amplified signal, a source coupled transistors for generating a control voltage according to output current of the summing circuit, and a first output transistor and a second output transistor for controlling current of the first output transistor and the second output transistor according to the control voltage of the source coupled transistor.

Operational amplifier with rail-to-rail common-mode input and output range

A control circuit for an operational amplifier and a method thereof are provided to dynamically modulate the operational amplifier for strong driving capability and power saving. The control circuit comprises a bias unit coupled to the operational amplifier and a control unit coupled to the bias unit. The bias unit normally outputs a bias signal to bias the operational amplifier so that the operational amplifier has a first driving capability. However, when the driving capability of the operational amplifier needs to be adjusted, the control unit receives a modulating signal and outputs a control signal according to the modulating signal. When the bias unit receives the control signal, the bias unit dynamically modulates the bias signal according to the control signal, and hence the driving capability of the operational amplifier is dynamically modulated in an indirect manner.

Control circuit for operational amplifier and method thereof

A current source with adjustable temperature coefficient is provided. The current source uses a first current generation unit and a second current generation unit to respectively produce a positive temperature coefficient current and a negative temperature coefficient current. A current addition unit is used to add the positive and negative temperature coefficient currents, and compose the positive and negative temperature coefficient currents according to a predetermined proportion. Finally, a reference current of adjustable temperature coefficient and value is output.

Current source with adjustable temperature coefficient

A slew rate enhancement circuit for adjusting a gamma curve including a main output stage, a monitoring stage, an assistant output stage and a gamma curve generating device is provided. The main output stage also generates a first push signal and a first pull signal according to the input voltage, and thereafter the second push signal and second pull signal are level shifted by the monitoring stage. A second push signal and second pull signal will turn on or turn off the assistant output stage to decided whether to output an assistant current to the load or not. The gamma curve generating device receives the assistant current to outputs at least one gamma reference voltage for adjusting a gamma curve. Specially, the improved compact circuit does not increase static operating current for the original operational amplifier and occupy a small chip area.

Slew rate enhancement circuit via dynamic output stage for adjusting gamma curve

A driving apparatus for driving a plurality of display devices of a panel is provided. The driving apparatus comprises a controllable current source and a plurality of current storage and duplicating apparatuses. Wherein, each of the current storage and duplicating apparatuses is coupled to the controllable current source and one of the display devices corresponding thereto to receive a first current from the controllable current source, and to output a second current which is equal, or proportional to the first current to drive the display apparatus.

Driving method and driving apparatus

A converter for an amplifying device having a first amplifier and a second amplifier is provided. The first amplifier and the second amplifier have a first tail current and a second tail current respectively. The converter includes a first compensating device and a second compensating device. The first compensating device is connected to the first amplifier, and under the control of the first tail current, determines whether to convert the first tail current to the second amplifier. The second compensating device is connected to the second amplifier, and under the control of the second tail current, determines whether to convert the second tail current to the first amplifier. There are two current paths between the first compensating device and the second compensating device and the converter can maintain the transconductance of the amplifying device at a substantially constant value.

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Taichung County, Taiwan

Kuang-Feng Sung