Abstract:
A fingerprint sensor device and an operation method thereof are provided. The fingerprint sensor device includes a driving electrode, a driving circuit, a fingerprint sensing plate, a reading circuit and a determination circuit. The driving circuit applies a driving signal to an object through the driving electrode. The fingerprint sensing plate has sensing electrodes configured to sense the object. The reading circuit reads the driving signal through the fingerprint sensing plate. During a period between a rising edge time point and its adjacent falling edge time point of the driving signal, the reading circuit respectively samples the driving signal in at least two different phases to obtain at least two sampling results and outputs a difference value of the at least two sampling results. The determination circuit checks the difference value to determine whether the object to be sensed is a real finger or a fake finger.
Abstract:
The present disclosure provides a driving device for driving a display device. The driving device includes a first charge sharing switch, a second charge sharing switch and one or more third charge sharing switches. The first charge sharing switch is coupled between two adjacent odd data channels of a plurality of data channels. The second charge sharing switch is coupled between two adjacent even data channels of the plurality of data channels. Each of the one or more third charge sharing switches is coupled between two adjacent ones of the plurality of data channels. A first charge sharing is performed when the first charge sharing switch is turned on.
Abstract:
An operational amplifier circuit including a main circuit, a compensation capacitor, a power circuit, and a set of switches is disclosed. The main circuit has an output terminal. The compensation capacitor has a first end connected to an internal node of the main circuit and a second end connected to the output terminal of the main circuit. The power circuit provides a current or a voltage as predetermined. The set of switches connects the power circuit to the compensation capacitor. When the main circuit is not in an output state, the set of switches is switched to allow the power circuit to provide the current or voltage to the compensation capacitor. When the main circuit is in the output state, the set of switches is switched to disconnect the power circuit from the compensation capacitor and allow the main circuit to return to an output circuit state and operate normally.
Abstract:
An operational amplifier circuit includes an output stage circuit. The output stage circuit includes a first and a second output transistors, a capacitor unit, and a switch unit. A drain of the first output transistor is coupled to a drain of the second output transistor via an output terminal of the output stage circuit. The switch unit is coupled between gates of the first and the second output transistors and coupled to a first terminal of the capacitor unit. A second terminal of the capacitor unit is coupled to the output terminal of the output stage circuit. The switch unit determines to conduct a signal transmission path between the gate of the first output transistor and the first terminal of the capacitor unit or conduct a signal transmission path between the gate of the second output transistor and the first terminal of the capacitor unit according to a control signal.
Abstract:
An operational amplifier module including an operational amplifier circuit and a comparator circuit is provided. The operational amplifier circuit includes an input stage circuit and an output stage circuit. The input stage circuit receives an input signal. The output stage circuit is coupled to the input stage circuit for enhancing the driving capability of the input signal. The comparator circuit is coupled to the output stage circuit for receiving the input signal. The comparator circuit determines whether the input signal changes so as to output an enable control signal to the output stage circuit to enhance the driving capability of the operational amplifier circuit. Furthermore, a method for enhancing the driving capability of the foregoing operational amplifier circuit is also provided.
Abstract:
A reading device and a reading method for a fingerprint sensor are provided. The reading device includes a switching circuit, a plurality of analog front end (AFE) circuits and a calculation circuit. The switching circuit is coupled to a plurality of pixel units of the fingerprint sensor. The AFE circuits are coupled to the switching circuit. The calculation circuit is coupled to the AFE circuits for calculating a plurality of pixel data of the pixel units. For a first pixel unit among the pixel units, the calculation circuit reads the first pixel unit by using different AFE circuits among the AFE circuits, so as to obtain a plurality of first original sensing values of the first pixel unit. The calculation circuit calculates the pixel data of the first pixel unit according to the plurality of first original sensing values.
Abstract:
A load driving apparatus for driving a plurality of loads is provided. The load driving apparatus includes an output stage module, a load driving module, and an output stage selection module. The output stage module includes a plurality of output stages. Each of the output stages is coupled to a corresponding one of the loads. The load driving module is coupled to the output stage module and outputs a driving signal to drive one of the loads through the output stage module. The output stage selection module is coupled between the output stage module and the load driving module and selects one of the output stages in the output stage module, so that the load driving module drives the load which is coupled to the selected output stage through the selected output stage. Furthermore, a grayscale voltage generating circuit including the foregoing load driving apparatus is also provided.
Abstract:
An operational amplifier, including an input stage circuit, an output stage circuit and a constant-gm circuit is provided. The input stage circuit provides a driving voltage according to an input voltage. Input terminals of the output stage circuit receive the driving voltage, and an output terminal of the output stage circuit provides an output voltage according to the driving voltage. The constant-gm circuit includes a constant-gm switch circuit, a current mirror circuit and a current mirror switch circuit. The constant-gm switch circuit controls the operation of the constant-gm circuit. The constant-gm switch circuit allows the current mirror circuit to operate during a transient time when the driving voltage is transited according to the driving voltage, so as to provide a compensated current for the input stage circuit. When the driving voltage is during a non-transient time, the current mirror switch circuit turns off the current mirror circuit.
Abstract:
A digital-to-analog convertor for a driving module of a display device is disclosed. The digital-to-analog convertor includes a plurality of switches, forming a tree structure with a plurality of stages for outputting one of a plurality of gamma voltages to an output end according to a plurality of bits of a digital input signal; and a bypass unit, coupled between a first output end of a first switch in the plurality of switches and the output end for adjusting a connection between the first output end and the output end according to a most significant bit in among the plurality of bits and the bits between the most significant bit and a first bit controlling the first switch in among the plurality of bits.
Abstract:
A display driver, which comprises: a first predetermined voltage level providing apparatus, for providing a first predetermined voltage level group comprising at least one first predetermined voltage level; a first image data providing apparatus, for outputting a first image data; and a detection controlling circuit, for determining if an output terminal of the first image data providing apparatus is pre-charged to the first predetermined voltage level according to a relation between an absolute value of a voltage level of the first image data and an absolute value of the first predetermined voltage level.