Abstract: An alternating current (AC) drive signal having a first frequency and a high logic level at a boosted supply voltage is applied to drive a capacitive sensing line of a capacitive touch panel. The boosted supply voltage is generated by boosting an input voltage. The voltage boosting is effectuate by a charge pump circuit operating synchronous to assertion of the AC drive signal with a charge transfer time that is adaptable to different capacitive load conditions.

Abstract: A method of differential self-capacitance measurement is used to enhance a signal-to-noise ratio of sense lines in a touch panel display, thereby improving touch sensor accuracy. The differential self-capacitance measurement is implemented for a touch panel using charge sharing between adjacent sense lines of the touch panel matrix. Sequential differential self-capacitance measurements can be compared with one another by computing the difference |CS1?CS2|?|CS2?CS1| to sense a change caused by an intervening event. By scanning the entire touch panel matrix, events can be tracked across the touch panel.

Abstract: Disclosed herein is an electronic device including a display layer generating display noise based on scanning thereof and a sensing layer including a plurality of sense lines. The display noise is capacitively coupled from the display layer to each of the plurality of sense lines of the sensing layer. A differential charge converter circuit has first and second differential inputs respectively coupled to corresponding ones of the plurality of sense lines, and first and second reference inputs. The first and second reference inputs of the differential charge converter circuit are coupled to voltage references during a reset period, and are decoupled from the voltage references during a scan period.

Abstract: A method of differential self-capacitance measurement is used to enhance a signal-to-noise ratio of sense lines in a touch panel display, thereby improving touch sensor accuracy. The differential self-capacitance measurement is implemented for a touch panel using charge sharing between adjacent sense lines of the touch panel matrix. Sequential differential self-capacitance measurements can be compared with one another by computing the difference |CS1?CS2|?|CS2?CS1| to sense a change caused by an intervening event. By scanning the entire touch panel matrix, events can be tracked across the touch panel.

Abstract: Disclosed herein is an electronic device including a display layer generating display noise based on scanning thereof and a sensing layer including a plurality of sense lines. The display noise is capacitively coupled from the display layer to each of the plurality of sense lines of the sensing layer. A differential charge converter circuit has first and second differential inputs respectively coupled to corresponding ones of the plurality of sense lines, and first and second reference inputs. The first and second reference inputs of the differential charge converter circuit are coupled to voltage references during a reset period, and are decoupled from the voltage references during a scan period.

Abstract: Disclosed herein is an electronic device including a sensing layer including a plurality of sense lines, and a plurality of single ended charge converter circuits each receiving input from a corresponding one of the plurality of sense lines. The electronic device also includes a plurality of current mirror circuits, each respectively mirroring output from one of the plurality of single ended charge converter circuits so as to produce two substantially identical outputs for each of the plurality of single ended charge converter circuits. There may be a plurality of subtractor circuits coupled to the plurality of current mirror circuits, with each of the plurality of subtractor circuits configured to output a voltage that is a function of a difference between outputs from two of the plurality of current mirror circuits associated with adjacent ones of the sense lines.

Abstract: A touch screen controller disclosed herein includes a circuit configured to generate a digital touch voltage comprises of samples, at a base sampling rate. The touch screen controller also includes a digital processing unit configured to analyze a first subset of samples of the digital touch voltage samples to determine noise content thereof, the first subset of samples corresponding to samples at a first investigated sampling rate that is a first function of the base sampling rate. The digital processing unit is also configured to analyze a second subset of samples of the digital touch voltage to determine noise content thereof, with the second subset of samples corresponding to samples at a second investigated sampling rate that is a second function of the base sampling rate, and determine a preferred sampling rate from among the first and second investigated sampling rates as a function of determined noise content thereof.

Abstract: An alternating current (AC) drive signal having a first frequency and a high logic level at a boosted supply voltage is applied to drive a capacitive sensing line of a capacitive touch panel. The boosted supply voltage is generated by boosting an input voltage. The voltage boosting is effectuate by a charge pump circuit operating synchronous to assertion of the AC drive signal with a charge transfer time that is adaptable to different capacitive load conditions.

Abstract: A circuit described herein includes a charge to voltage converter circuit having an input coupled to receive a sense signal from a sense node associated with a mutual capacitance to be sensed, and an output. A reset switch is coupled between the output of the charge to voltage converter circuit and the input of the charge to voltage converter. An accumulator circuit is configured to accumulate voltages at the output of the charge to voltage converter circuit and to generate an accumulator output signal. Control circuitry is configured to generate control signals for the reset switch and accumulator circuit so as to reduce noise in the accumulator output signal.

Abstract: A method of differential self-capacitance measurement is used to enhance a signal-to-noise ratio of sense lines in a touch panel display, thereby improving touch sensor accuracy. The differential self-capacitance measurement is implemented for a touch panel using charge sharing between adjacent sense lines of the touch panel matrix. Sequential differential self-capacitance measurements can be compared with one another by computing the difference |CS1?CS2|?|CS2?CS1| to sense a change caused by an intervening event. By scanning the entire touch panel matrix, events can be tracked across the touch panel.

Abstract: An activity detector for a differential signal formed by two components may include a current source connected to a power supply line, and a first transistor has a drain being powered by the current source, and has a source that forms a first input terminal receiving a first component of the differential signal. A second transistor has a drain being powered by the current source, and has a source forms a second input terminal receiving the second component of the differential signal. A bias circuit applies a potential to the gates of the first and second transistors, establishing a balance condition where all the current from the current source is distributed between the two transistors when the first and second input terminal potential is equal to a threshold value. An activity indication terminal is taken from the drains of the first and second transistors.

Abstract: The present disclosure includes calibration circuitry for adjusting the bandwidth of at least one sub-converter of an interleaved analog to digital converter (ADC), the at least one sub-converter having an input switch coupled to an input line of the ADC, the calibration circuitry having a control circuit adapted to adjust a bulk voltage of a transistor forming the input switch.

Abstract: A switched capacitor amplifier having an amplification unit adapted to amplify a differential signal; a first switched capacitor block including a first plurality of capacitors operable to sample a first differential input signal during a first sampling phase and to drive the amplification unit during a first drive phase; and a second switched capacitor block including a second plurality of capacitors operable to sample a second differential input signal during a second sampling phase and to drive the amplification unit during a second drive phase.

Abstract: A switch for an analog signal may include a main MOS transistor whose source forms an input terminal of the switch and whose drain forms an output terminal of the switch, a capacitor having a first terminal permanently connected to the source of the main transistor, a circuit for charging the capacitor, and a first auxiliary transistor configured to connect the second terminal of the capacitor to the gate of the main transistor in response to a control signal. The charge circuit may include a resistor permanently connecting the second terminal of the capacitor to a power supply line. The capacitor and the resistor may form a high-pass filter having a cutoff frequency lower than the frequency of the analog signal.

Abstract: Device for processing an analogue signal, comprising an analogue-digital converter with a pipelined architecture having an offset, and compensation means configured to compensate for the said offset, the said compensation means comprising digital correction means configured to correct the integer portion of the offset based on the digital signal delivered by the analogue-digital converter, and analogue correction means included in the last stage of the analogue-digital converter and configured to correct the decimal portion of the offset.

Abstract: An activity detector for a differential signal formed by two components may include a current source connected to a power supply line, and a first transistor has a drain being powered by the current source, and has a source that forms a first input terminal receiving a first component of the differential signal. A second transistor has a drain being powered by the current source, and has a source forms a second input terminal receiving the second component of the differential signal. A bias circuit applies a potential to the gates of the first and second transistors, establishing a balance condition where all the current from the current source is distributed between the two transistors when the first and second input terminal potential is equal to a threshold value. An activity indication terminal is taken from the drains of the first and second transistors.

Abstract: A switch for an analog signal may include a main MOS transistor whose source forms an input terminal of the switch and whose drain forms an output terminal of the switch, a capacitor having a first terminal permanently connected to the source of the main transistor, a circuit for charging the capacitor, and a first auxiliary transistor configured to connect the second terminal of the capacitor to the gate of the main transistor in response to a control signal. The charge circuit may include a resistor permanently connecting the second terminal of the capacitor to a power supply line. The capacitor and the resistor may form a high-pass filter having a cutoff frequency lower than the frequency of the analog signal.

Abstract: A device may include a programmable gain amplifier and an analog-digital converter with pipeline architecture having several stages. The first stage of the analog-digital converter may incorporate the programmable gain amplifier and an analog-digital conversion circuit with a programmable threshold.

Abstract: The common-mode voltage of a switched-capacitor system is controlled by determining a current common-mode voltage of the switched-capacitor system, converting (in a flow-through conduction cell) the difference between the current common-mode voltage and a desired common-mode voltage into a resultant current, and reinjecting this resultant current into the switched-capacitor system via a resistive path.

Abstract: Device for processing an analogue signal, comprising an analogue-digital converter with a pipelined architecture having an offset, and compensation means configured to compensate for the said offset, the said compensation means comprising digital correction means configured to correct the integer portion of the offset based on the digital signal delivered by the analogue-digital converter, and analogue correction means included in the last stage of the analogue-digital converter and configured to correct the decimal portion of the offset.