Raydium Semiconductor Corporation

Century Semiconductor, Inc.

Raydlum Semiconductor Corporation

Chin-Chieh Chao

Ko-Yang Tso

Hui-Wen Miao

Ren-Feng Huang

Yann-Hsiung Liang

Hui Wen Miao

Yong-Nien Rao

Keh-Yung Tso

Tsen-Shau Yang

Jieh-Tsorng Wu

Chih-Yu Lee

Keh-La Lin

A digital-to-analog (D/A) converter comprises a decoder apparatus and an operational amplifier. The decoder apparatus comprises first and second decoder unit. The first decoder unit selects a voltage of first voltage set as first and second voltage in response to a value of first gray level set. The second decoder unit selects first border voltage of second voltage set as the first and the second voltages and second border voltage of that as the first and the second voltages in response to the maximum and the minimum value of second gray level set respectively. The second decoder unit further selects the first and the second boarder voltage as the first and the second voltage respectively in response to an intermediate value of the second gray level set. The operational amplifier generates a pixel voltage having level between the first and the second voltage accordingly.

Digital-to-analog converter and method thereof

A sampling phase selection method for a data stream is provided, wherein the data stream has a variable data rate in a fixed time period. The method comprises generating a calibration signal, wherein the time interval of the calibration signal is longer than the fixed time period of the data stream, generating a first clock sequence and a subsequent second clock sequence, wherein the first and the second clock sequence are composed of a plurality of continuous clock phases and the number of the clock phases of the first clock sequence are the same as that of the clock phases of the second clock sequence, selecting one of the phases of the first and the second clock sequence, in turn, to provide a sampling phase, performing a plurality of samplings on the data stream to generate a flag signal, and selecting a final sampling phase according to the flag signals with different sampling phases.

Sampling phase selection method for a stream of data bits

The current disclosure discloses a sampling phase selection method for a data stream, wherein the data stream has a variable data rate in a fixed time period. The method comprises the following steps: generating M section signals with the same time interval during the fixed time period of the data stream, generating N continuous clock phases according to a rising edge of each of the section signals, selecting one of the continuous clock phases corresponding to the different section signals in turn to provide a sampling phase, performing a plurality of samplings on the data stream to generate a flag signal, repeating the selecting and the sampling steps to generate N flag signals corresponding to the different section signals, and selecting a final sampling phase according to the N flag signals corresponding to the different section signals.

A signal circuit includes a clock terminal for transmitting a reference clock and a data terminal for transmitting an input/output data. In an embodiment, the frequency of the reference clock is one-eighth of the bit rate of the input/output data.

Signal circuit

A sampling clock selection module for a serial data stream is disclosed. The sampling clock selection module includes a multi-phase generation circuit, a sampling circuit, a comparison unit and a logic operation unit. The multi-phase generation circuit generates a plurality of non-overlapping clock phases derived from a reference clock signal. The phase selection circuit selects a sampling clock phase under a calibration mode. The sampling circuit performs sampling on the serial data stream a plurality of times to generate a plurality of sampled values in response to the sampling clock phase. The comparison unit compares the sampled values with the serial data stream so as to update a plurality of flag signals. The logic operation unit performs a logic operation on the flag signals so as to select a sampling clock phase under a normal operation mode from the clock phases.

Sampling clock selection module of serial data stream

The invention discloses a driving circuit system and a method of elevating a slew rate of an operational amplifier. The driving circuit system comprises an operational amplifier, a judging module and a bias enhancing module. The operational amplifier has an input stage driven by a bias current. The bias enhancing module is electrically connected to the judging module and the input stage of the operational amplifier respectively. The judging module is used to generate a bias enhancing signal according to an edge-trigger of a control signal. When the bias enhancing module receives the bias enhancing signal, the bias enhancing module provides an additional current, which cooperates with the bias current, for driving the input stage of the operational amplifier, so as to elevating a slew rate of the operational amplifier.

Driving circuit system and method of elevating slew rate of operational amplifier

A power-on screen pattern correcting apparatus is for correcting start output data of output terminals of a source driver such that a power-on screen pattern of a display is substantially uniform. The correcting apparatus comprises a flip-flop, a first logic unit and a second logic unit. The flip-flop controls a level of an inner signal to be substantially equal to a low signal level in response to a low level of a power start signal. The first logic unit enables a first signal in response to the low level of the inner signal or a low level of a high-impedance control signal. The second logic unit enables a second signal such that the output terminals are coupled to a charge sharing line and the power-on screen pattern is uniform in response to the low level of the inner signal or a low level of a charge-sharing control signal.

Power-on screen pattern correcting apparatus and source driver using the same

A flip-flop is provided. The flip-flop is used in a shift register in a source driver. The flip-flop is used to receive a first clock signal, an input signal and output an output signal. The output signal is fed back to the flip-flop. The flip-flop includes a flop core for receiving the input signal and output the output signal. When the input signal and the output signal are all disabled, the flop core is disabled to function. When the input signal or the output signal is enabled, the flop core is enabled to function to output the output signal.

Flip-flop and shift register

A receiving circuit is provided for receiving a data signal and a clock signal, which are RSDS signals, and outputting an output data signal to a data driver. The receiving circuit includes a data comparator, a data intermediate circuit, a clock comparator, a clock intermediate, and a flip-flop. The data comparator, driven with a data bias current, receives the data signal, and outputs a compared data signal. The clock comparator, driven with a clock bias current, receives the clock signal, and outputs a compared clock signal. The flip-flop receives the compared data signal via the data intermediate circuit and the compared clock signal via the clock intermediate circuit. The phase difference between the compared data signal and the compared clock signal is improved by adjusting the data and the clock bias currents.

Receiving circuit and method thereof

A voltage-clamping device used in an operational amplifier is provided. The operational amplifier comprises a first transistor. The cross-voltage between the gate and the source of the first transistor is near to a specific voltage and the cross-voltage between the drain and the source of the first transistor is not equal to zero, so as to generate a big substrate current. The voltage-clamping device comprises a second transistor whose source and gate are respectively coupled to the drain of the first transistor and used for receiving a bias signal, so that the second transistor is biased in saturation region, and the voltage at the source of the second transistor is made equal to the difference between the bias signal and the threshold voltage of the second transistor. Thus, the cross-voltage between the drain and the source of the first transistor is reduced and the substrate current is reduced accordingly.

Voltage-clamping device and operational amplifier and design method thereof

An interpolating D/A converter architecture includes a reference voltage generator, a decoding switch network, a routing switch, and an interpolating buffer. The reference voltage generator generates a plurality of reference voltages. The decoding switch network is coupled to the reference voltage generator for selecting two reference voltages from the plurality of reference voltages in response to the plurality of high bits of digital video signals. The routing switch is coupled to the decoding switch network for selectively providing a first reference voltage and a second reference voltage in response to a plurality of low bits of the digital video signals. And the interpolating buffer is coupled to the routing switch for outputting an interpolated analog signal in response to the first reference voltage and the second reference voltage. Eventually, the present invention can save half the D/A reference lines and half the associated decoding switch rows, and thereby save the die cost.

Interpolating digital to analog converter and TFT-LCD source driver using the same

The present invention discloses a single-ended sense amplifier including an output circuit having an output terminal for indicating a state of a bitline node. In addition, a noise margin circuit; and an n-channel transistor are provided for coupling or decoupling an input terminal of the output circuit with the bitline node. The variable logic-threshold inverter has a larger logic threshold voltage in response to a lower voltage level of a precharge signal and a smaller logic-threshold voltage in response to a higher voltage level of the precharge signal. The difference between the two logic-threshold voltages represents the possible noise margin. Furthermore, a power down control circuit is provided to be coupled to the bitline node for reducing the static power consumption of the single-ended sense amplifier. The single-ended sense amplifier according to the present invention provides a higher and adjustable noise margin and occupies a smaller area on a semiconductor wafer.

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Hsinchu, Taiwan

Chin-Chieh Chao