Tpk Touch Solutions Inc.

Alpha Networks Inc.

Ralink Technology Corporation

Chun-Hsueh Chu

Jui-Jung Chiu

Jiunn-Tsair Chen

Rong-Fa Kuo

Jui-jung Chiu

A characteristic impedance of an electric transmission line is measured by way of extraction. In the method, a first probe and a second probe are provided, wherein the first probe and the second probe are separable and independently operable probes. A first characteristic impedance of a first circuit where a first terminal of the first probe and a first terminal of the second probe are directly interconnected to each other is first measured. Then a second characteristic impedance of a second circuit where the first terminal of the first probe and the first terminal of the second probe are connected to opposite terminals of the electric transmission line, respectively, is measured. The characteristic impedance of the electric transmission line can then be obtained according to the first characteristic impedance and the second characteristic impedance.

Method for measuring characteristic impedance of electric transmission line

A controlling system of a touch panel comprises of a drive signal generating circuit, a sensing module for sensing a waveform signal from the touch panel, and a signal processing module for enabling and disabling the drive signal generating circuit based on the signal outputted by the sensing module. Therefore, the mentioned controlling system can support the active and the passive touch modes. In addition, the present invention further provides a controlling method of the touch panel and a stylus pen applied to the mentioned controlling system.

Controlling system and a controlling method of a touch panel, and a stylus pen for applying to the touch panel

The present invention relates to a control circuit and control method for detecting the capacitance of a touch panel. The control circuit comprises: a signal-detecting circuit for charging a sensing wire of the touch panel to obtain an intensity signal of the sensing wire; an intensity/frequency conversion unit for converting the intensity signal into a frequency signal, the frequency of which corresponds to the level of the intensity signal; and a frequency-analyzing unit for analyzing the frequency signal to obtain a signal amount of the corresponding sensing wire. The control circuit for the capacitive touch panel has a good SNR, which will not be affected or lowered by noise signals in the circuit environment, and is constituted of simple components to reduce the occupied area on the chip and lower the cost.

Control circuit for sensing capacitive changes of a touch panel and a method thereof

A control circuit for a sensing electrode array is described. The control circuit for the sensing electrode array includes a signal intensity analyzer, an intensity-to-phase frequency converter, and a phase frequency analyzing unit. The signal intensity analyzer obtains an intensity signal corresponding to a sensing signal of each sensing line of the sensing electrode array, wherein each intensity signal is a direct-current signal. The intensity-to-phase frequency converter generates a phase frequency signal based on the intensity signal. At least the phase or the frequency of the phase frequency signal is related to the level of the corresponding intensity signal. The phase frequency analyzing unit obtains a signal magnitude of the corresponding sensing line according to each phase frequency signal. The control circuit for the sensing electrode array enhances the operating speed and the signal-to-noise ratio of the touch control sensing system without increasing the manufacturing cost.

Control circuit and method for sensing an electrode array and touch control sensing system using the same

A RF transceiver includes an antenna, a receiver, a baseband circuit, a transmitter, and a T/R switch circuit. The T/R switch circuit is used for coupling the antenna and the receiver or coupling the antenna and the transmitter. The T/R switch circuit is coupled to the baseband circuit so as to receive biases provided from the baseband circuit. The T/R switch circuit includes four transistors and a power detector. The power detector detects the power of the output signal of the T/R switch circuit, so that the baseband circuit can adjust biases provided to the T/R switch circuit according to the power of the output signal.

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Hsinchu, Taiwan

Chun-Hsueh Chu