Himax Technologies, Inc.

Zong-You Hou

Yaw-Guang Chang

Jia-Ming He

Yi-Yang Tsai

Wei-Hsien Yeh

A touch detection circuit includes at least one driving signal generator. The least one driving signal generator receives a first power voltage and a second power voltage as operation powers. Each of the at least one driving signal generator generates at least one driving signal based on the first power voltage and a second power voltage and each of the at least one driving signal swings between a first voltage and a second voltage, wherein the first voltage is a positive voltage and the second voltage is a negative voltage.

Touch detection circuit

The fingerprint sensing circuit includes a photo detector, a capacitor, a current mirror and a switch circuit. The capacitor has a first terminal electrically connected to the first terminal of the photo detector. The current mirror has an input terminal electrically connected to the first terminal of the photo detector and an output terminal electrically connected to a sensing line. In an exposure period, the switch circuit turns off the current mirror. In a sensing period, the switch circuit turns on the current mirror to generate a current on the sensing line, and the detecting circuit is configured to generate a fingerprint signal according to the current.

Display device and fingerprint sensing circuit

A fingerprint recognition driving device includes a plurality of light sensors and a plurality of signal processing circuits. The light sensors respectively generate a plurality of sensing signals. The signal processing circuits respectively coupled to the light sensors, for processing the sensing signals to generate a plurality of processed sensing signals. During each of a plurality of sensing periods, one of the signal processing circuits provides corresponding processed sensing signal with a first polarity, and each of the other signal processing circuits provides corresponding processed sensing signals with a second polarity, and the first polarity is different from the second polarity. The signal processing circuits generates an output signal according to the processed sensing signals.

Fingerprint recognition driving device

A detection circuit adaptable to a fingerprint detection system includes an integrating amplifier coupled to receive a photo-detected voltage from a sensor panel and configured to generate time integral of the photo-detected voltage, thereby resulting in a time-integral signal; and an analog-to-digital converter (ADC) that converts the time-integral signal into a digital form. A first common-mode voltage of the sensor panel is coupled to the integrating amplifier to prevent noise occurred in the first common-mode voltage from affecting the time-integral signal.

Fingerprint detection system and a detection circuit adaptable thereto

A low power consumption boost circuit for providing high driving voltage of a touch circuit is provided. The low power consumption boost circuit includes a charge pump circuit, two digital-to-analog converters (DACs), and a switch circuit. The charge pump circuit receives a system voltage and correspondingly outputs a positive output voltage twice the system voltage and a negative output voltage with opposite polarity as the system voltage. One of the DACs receives the positive output voltage from the charge pump circuit as supply voltage, and the other DAC receives the negative output voltage from the charge pump circuit as supply voltage. The switch circuit is connected between the DACs and the touch circuit. The DACs are connected between the charge pump circuit and the switch circuit. The DACs are alternately connected to the touch circuit by controlling the switch circuit, thereby driving the touch circuit alternately.

Low power consumption boost circuit for providing high driving voltage of touch circuit

The fingerprint sensing circuit includes pixel sensors with photo sensors. Sensing currents produced by first pixel sensors are averaged. The average current is subtracted from sensing current produced by second pixel sensors to generate a difference current. During a capture period, a converting circuit outputs a digital signal in response to the difference current. This circuit aims to reduce noise in fingerprint recognition technology.

Fingerprint sensing circuit

A display device is disclosed, which includes a display panel and a detection circuit. The display panel has pixels configured to display an image. The pixels include display and photo sensing pixels that are arranged in sensing channels. Each display and photo sensing pixel includes a display region and a photo sensing region. The display region emits light. The photo sensing region detects the light emitted by the display region and reflected from a biometric object and to convert the reflected light into photo detection signals. The detection circuit has differential signal processing circuitries that are coupled to the photo sensing regions of the display and photo sensing pixels. Each differential signal processing circuitry performs a differential operation on the photo detection signals of adjacent two of the sensing channels to generate a difference signal that is used to construct a biometric pattern corresponding to the biometric object.

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Tainan, Taiwan

Zong-You Hou